Foundation structure and its construction method, and half-precast beams

Abstract

To provide a foundation structure and construction method that can improve quality by reducing the labor involved in setting up and removing formwork, eliminating or reducing the labor required for reinforcing beams. [Solution] The construction method for the foundation structure includes a support leg installation step of forming two rows of support legs 60A by embedding the lower parts of multiple support legs 60 for leveling in lean concrete; a reinforced precast concrete slab installation step of placing and fixing a pair of reinforced precast concrete slabs 50 on the two rows of support legs 60A with parts of the corresponding reinforcing bars 10 of each crossing each other and a gap S1 between them; a reinforcement placement step of arranging reinforcement bars 18 for the pressure slab within the height range of the support legs 60; and a concrete pouring step of pouring concrete for the pressure slab in the lower gap S2, pouring concrete for the foundation beam in the gap S1 to construct the pressure slab 80 and the foundation beam 100 which is a half-precast beam, and constructing the foundation structure 200.

Description

Technical Field

[0001] The present invention relates to a foundation structure, its construction method, and a half-precast beam.

Background Art

[0002] When constructing a reinforced concrete foundation beam (hereinafter referred to as a reinforced concrete beam) that constitutes a building together with a pressure-resistant slab on-site, as a measure to save labor in installing temporary members and improve workability, a pair of precast concrete slabs manufactured at a factory or the like are installed with a gap at the beam construction position on-site, beam reinforcement is arranged in the gap, and concrete is placed in the gap while using the precast concrete slab as a formwork (side formwork) to construct the reinforced concrete beam. This method may be applied.

[0003] Thus, since a part of the reinforced concrete beam is formed by the precast concrete slab, the reinforced concrete beam constructed by such a construction method can be called a half-precast beam. By applying the half-precast beam, labor can be saved when installing the formwork by using the precast concrete slab as a formwork, and since the precast concrete slab remains as a component of the half-precast beam, labor can also be saved when demolding.

[0004] Furthermore, the formwork can be included in the cover thickness of the reinforcement, the precast part can be expected to have structural strength, and since the precast concrete slab is factory-manufactured, it is possible to suppress problems such as concrete janka and cracking that occur when constructing the entire reinforced concrete beam on-site, and by ensuring the reinforcement accuracy, the quality can be improved.

[0005] Furthermore, in the case of so-called full precast beams, where the entire reinforced concrete beam is formed from precast concrete panels, the weight becomes heavy, reducing transportability, and construction costs tend to increase because large-capacity lifting equipment is required during construction. However, these problems can be resolved by applying half-precast beams.

[0006] Here, Patent Document 1 proposes a method for constructing beams. This method for constructing a reinforced concrete foundation beam involves embedding the main reinforcement bars at the bottom of the beam in the longitudinal direction and the stirrup bars in the short direction, while precast plates are fabricated in advance with one end of the stirrup bars exposed from the side to form a stirrup anchorage section and the other end exposed from the top surface. A pair of precast plates are then placed vertically on a concrete slab for the floor so that the exposed sides of the stirrup anchorage sections face each other. Intermediate beam reinforcement bars are placed in the space formed by the opposing placement of the pair of precast plates to satisfy the required amount of main reinforcement bars and shear reinforcement bars, and concrete is poured into the space to anchor the intermediate beam reinforcement bars and stirrup anchorage sections in the concrete, thereby constructing the foundation beam. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2016-79695 [Overview of the project] [Problems that the invention aims to solve]

[0008] According to the beam construction method described in Patent Document 1, when constructing reinforced concrete beams, the work related to beam formwork at the construction site can be significantly reduced, thereby achieving labor savings in on-site work.

[0009] By the way, when constructing a foundation structure by placing a precast concrete slab that forms the foundation beam on top of the reinforcement for the pressure slab, arranging the reinforcement for the foundation beam inside the precast concrete slab, and then pouring concrete to embed the reinforcement for the pressure slab and the foundation beam, the beam depth of the foundation beam is the height from the top edge of the pressure slab upwards, and the thickness of the pressure slab is not taken into consideration. Therefore, if you want to construct a foundation beam with a beam depth that includes the thickness of the pressure slab, you need to make the beam depth of the foundation beam above the top edge of the pressure slab the beam depth that includes the thickness of the pressure slab.

[0010] Thus, in order to eliminate the need to construct a foundation beam with a beam depth that has the thickness of the pressure-resistant slab added above it, one possible solution is to install a precast concrete slab by dropping it down to the position below where the reinforcement for the pressure-resistant slab is placed. However, in this case, the precast concrete slab interferes with the reinforcement for the pressure-resistant slab, making it impossible to place the reinforcement and preventing the cross-section of the pressure-resistant slab from being effectively incorporated into the cross-section of the foundation beam.

[0011] The present invention has been made in view of the above problems, and aims to provide a foundation structure and construction method therefor, as well as a half-precast beam, in a foundation structure having a foundation beam made of a half-precast beam equipped with a precast concrete slab and a pressure-resistant slab, in which interference between the precast concrete slab and the reinforcing bars for the foundation beam can be prevented, the beam depth of the foundation beam can be viewed from a position below the pressure-resistant slab, and the cross-section of the pressure-resistant slab can be effectively incorporated into the cross-section of the foundation beam. [Means for solving the problem]

[0012] To achieve the above objective, one aspect of the construction method for a foundation structure according to the present invention is: A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The support leg installation step involves arranging the support legs at intervals along the longitudinal direction of the foundation beam, with the lower parts of the support legs for leveling embedded in the lean concrete, and arranging the support legs at intervals along the width direction of the foundation beam to form two rows of support legs. A precast concrete slab with reinforced steel is installed by placing and fixing a pair of precast concrete slabs with reinforced steel bars, each of which has at least one of the upper or lower main reinforcement bars connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, with a portion of each reinforcing bar embedded at intervals along the longitudinal direction of the precast concrete slab, and the lower part of each reinforcing bar protruding below the precast concrete slab, on the two rows of support legs, with the corresponding portions of the reinforcing bars of both slabs crossing each other and a gap between them. The reinforcement process involves arranging reinforcing bars for the pressure-resistant plate within the height range of the support legs, The present invention is characterized by a concrete pouring step, in which concrete for the pressure slab is poured so as to bury the reinforcement bars for the pressure slab and each of the reinforcing bars below it, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure slab and the foundation beams.

[0013] According to this embodiment, a pair of reinforced precast concrete slabs, to which at least one of the upper or lower main reinforcements is connected, are embedded at intervals along the longitudinal direction of the precast concrete slab, with the lower part of each reinforcement protruding below the precast concrete slab. These slabs are then placed and fixed on two rows of support legs, each consisting of multiple support legs for leveling, the lower part of which is embedded in lean concrete. After this, reinforcement for the pressure slab is placed within the height range of the support legs, and concrete for the pressure slab is poured so as to embed the reinforcement for the pressure slab and the lower part of each reinforcement to construct the pressure slab. Furthermore, concrete for the foundation beam is poured into the gaps to construct the foundation beam, which is a half-precast beam. This prevents interference between the precast concrete slab and the reinforcement for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and effectively incorporating the cross-section of the pressure slab into the cross-section of the foundation beam. Here, the reinforcing bars for the pressure-resistant slab are placed between the lower parts of each reinforcing bar that protrude below the precast concrete slab, ensuring that they do not interfere with the other reinforcing bars.

[0014] Furthermore, when a pair of precast concrete panels with reinforced steel are installed, the beam reinforcement is automatically arranged. This allows for labor savings in formwork installation and removal using precast concrete panels, while eliminating or reducing the labor required for beam reinforcement arrangement. Moreover, since the panels are manufactured in a factory, quality can be ensured.

[0015] Furthermore, by overlapping the reinforcing bars of both precast concrete slabs with reinforced steel, it is possible to form a half-precast beam that has high torsional strength and sufficient restraint area, thus ensuring ductility, and a foundation structure in which this half-precast beam and pressure-resistant slab are integrated.

[0016] In this case, if the beam width of the foundation beam is small, it is extremely difficult for workers to enter the pair of precast concrete slabs to perform reinforcement work. Similarly, even with foundation beams having a high beam depth of about 2m to 3m, it is difficult to perform reinforcement work inside the pair of precast concrete slabs. In contrast, this embodiment eliminates or reduces the need to perform reinforcement work inside the pair of precast concrete slabs, which is desirable because it significantly improves the constructability of the foundation beam and the foundation structure consisting of this foundation beam and pressure-resistant slab.

[0017] Furthermore, other embodiments of the construction method for the foundation structure according to the present invention are: A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The support leg installation step involves arranging the support legs at intervals along the longitudinal direction of the foundation beam, with the lower parts of the support legs for leveling embedded in the lean concrete, and arranging the support legs at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A precast concrete slab with reinforcement bars is installed by placing and fixing a pair of precast concrete slabs with reinforcement bars, each of which has a corresponding longitudinal reinforcement bar tied or welded to the corrugated reinforcement bar or longitudinal reinforcement bar of the respective precast concrete slab, with the lower part of each reinforcement bar protruding below the precast concrete slab, on the two rows of support legs, with parts of the corresponding reinforcement bars of both slabs crossing each other and a gap between them. The reinforcement process involves arranging reinforcing bars for the pressure-resistant plate within the height range of the support legs, The present invention is characterized by a concrete pouring step, in which concrete for the pressure slab is poured so as to bury the reinforcement bars for the pressure slab and each of the reinforcing bars below it, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure slab and the foundation beams.

[0018] According to this embodiment, a pair of reinforced precast concrete slabs is provided, each comprising one or two separate longitudinal bars and corrugated reinforcing bars (truss bars) that extend longitudinally and exhibit a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, are connected to the separate reinforcing bars, with the lower part of each reinforcing bar protruding below the level of the precast concrete slab, with the lower part being embedded in lean concrete. After placing and fixing the slab on two rows of support legs consisting of multiple support legs for adjustment, reinforcement bars for the pressure slab are placed within the height range of the support legs, and concrete for the pressure slab is poured so as to bury the area below the reinforcement bars and each reinforcing bar to construct the pressure slab. Furthermore, concrete for the foundation beam is poured into the gaps to construct the foundation beam, which is a half-precast beam. This prevents interference between the precast concrete slab and the reinforcement bars for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and effectively incorporating the cross-section of the pressure slab into the cross-section of the foundation beam.

[0019] In addition, with respect to separately provided reinforcing bars in which at least separate vertical bars are embedded in a precast concrete slab, the entire substantially U-shaped or substantially L-shaped reinforcing bars that are bundled or the like are embedded in the post-cast concrete body, thereby enhancing the shear reinforcement effect. As a result, even if the degree of integration between the precast concrete slab and the post-cast concrete body is not good, a high shear reinforcement effect is achieved by the reinforcing bars having a substantially U shape or a substantially L shape.

[0020] Furthermore, when placing the concrete for the foundation beam during the construction of the post-cast concrete body, with respect to the pressure acting on the inside of the precast concrete slab and the earth pressure acting when backfilling the earth acting on the outside of the precast concrete slab before placing the concrete for the foundation beam, the vertical bars, the separately provided vertical bars, and the corrugated reinforcing bars between them can resist in the same mechanism as a truss beam.

[0021] Another aspect of the construction method of the foundation structure according to the present invention is In the support leg installation step, a cross member is spanned across the two rows of support leg rows, and a leg fixing member for fixing the legs of the precast concrete slab with reinforcing bars is installed on the cross member. In the precast concrete slab with reinforcing bars installation step, the legs of the precast concrete slab with reinforcing bars are fixed to the leg fixing member.

[0022] According to this aspect, by installing a leg fixing member on the cross member spanned across the two rows of support leg rows and fixing the legs of the precast concrete slab with reinforcing bars, a pair of precast concrete slabs with reinforcing bars can be placed in a stable posture with respect to the two rows of support leg rows.

[0023] Another aspect of the construction method of the foundation structure according to the present invention is The support leg for level adjustment includes an insert embedded in the disposable concrete, a bolt having a male screw screwed into the female screw of the insert, and a nut having its lower part fitted into the insert and embedded in the disposable concrete.

[0024] According to this embodiment, the support leg for level adjustment has an insert embedded in the lean concrete, a bolt with a male thread that screws into the female thread, and a nut into which the lower part of the insert is fitted and embedded in the lean concrete. Thus, the installation level of the reinforced precast concrete slab can be adjusted as desired by the support leg which is fixed in a stable position relative to the lean concrete.

[0025] Furthermore, other embodiments of the construction method for the foundation structure according to the present invention are: The support legs for leveling are concrete blocks, each having an engagement key on its upper part for securing the legs of the reinforced precast concrete slab.

[0026] According to this embodiment, the support legs for level adjustment are concrete blocks equipped with engaging keys on top for fixing the legs of the reinforced precast concrete slab. This allows the reinforced precast concrete slab to be placed in a stable position on the heavy concrete blocks, and its installation level to be adjusted as desired.

[0027] Furthermore, other embodiments of the construction method for the foundation structure according to the present invention are: A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, A lean concrete layer with multiple recesses on its top surface is constructed. A precast concrete slab with reinforcement bars is installed by fitting the lower parts of the support legs into corresponding recesses, with the corresponding parts of the reinforcement bars of both slabs crossing each other and a gap between them, and the lower parts of the support legs fitting into corresponding recesses, wherein at least one of the upper or lower main reinforcement bars is connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, a portion of each reinforcement bar is embedded at intervals along the longitudinal direction of the precast concrete slab, the precast concrete slab is provided with multiple support legs below it, a lower gap is provided between adjacent support legs, and the lower part of each reinforcement bar is located in the lower gap, and the precast concrete slab with reinforcement bars of both slabs crossing each other and a gap is provided between them, and The reinforcement process involves placing reinforcing bars for the pressure-resistant plate within the height range of the aforementioned lower gap, The present invention is characterized by a concrete pouring step, in which concrete for the pressure slab is poured so as to bury the reinforcement bars for the pressure slab and each of the reinforcing bars below it, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure slab and the foundation beams.

[0028] According to this embodiment, a pair of reinforced precast concrete slabs, to which at least one of the upper or lower main reinforcements is connected, are embedded at intervals along the longitudinal direction of the precast concrete slab. These slabs are equipped with multiple support legs below them, with a lower gap between adjacent support legs. The lower part of each reinforcement is located in the lower gap. After fitting the lower part of each support leg into multiple recesses on the upper surface of the lean concrete, reinforcement for the pressure slab is placed within the height range of the lower gap. Concrete for the pressure slab is poured so as to embed the reinforcement for the pressure slab and the lower parts of each reinforcement to construct the pressure slab. Furthermore, concrete for the foundation beam is poured into the gap to construct the foundation beam, which is a half-precast beam. This prevents interference between the precast concrete slab and the reinforcement for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and effectively incorporating the cross-section of the pressure slab into the cross-section of the foundation beam.

[0029] Furthermore, other embodiments of the construction method for the foundation structure according to the present invention are: A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, A lean concrete layer with multiple recesses on its top surface is constructed. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A precast concrete slab with reinforcement is installed by fitting the lower parts of the support legs into the corresponding recesses, with the wavy reinforcement bars or longitudinal bars of each of the aforementioned separate reinforcing bars tied or welded to the corresponding longitudinal bars of the reinforcing bars, and the precast concrete slab having a plurality of support legs below it, with a lower gap provided between adjacent support legs, and the lower part of each reinforcement bar located in the lower gap, with the corresponding parts of the reinforcing bars of both slabs crossing each other and a gap provided between them, The reinforcement process involves placing reinforcing bars for the pressure-resistant plate within the height range of the aforementioned lower gap, The present invention is characterized by a concrete pouring step, in which concrete for the pressure slab is poured so as to bury the reinforcement bars for the pressure slab and each of the reinforcing bars below it, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure slab and the foundation beams.

[0030] According to this embodiment, a pair of reinforced precast concrete slabs is provided with a plurality of support legs below it, with a lower gap between adjacent support legs, and the lower part of each reinforcement bar is located in the lower gap. After fitting the lower part of each support leg into multiple recesses on the top surface of the lean concrete, reinforcement bars for the pressure slab are placed within the height range of the lower gap, and the pressure slab concrete is poured so as to bury the lower part of the pressure slab reinforcement bars and each reinforcing bar to construct the pressure slab. Furthermore, concrete for the foundation beam is poured into the gap to construct the foundation beam, which is a half-precast beam. This prevents interference between the precast concrete slab and the reinforcement bars for the foundation beam, allows the beam depth of the foundation beam to be seen from a position below the pressure slab, and effectively incorporates the cross-section of the pressure slab into the cross-section of the foundation beam.

[0031] Furthermore, in another embodiment of the construction method for the foundation structure according to the present invention, The aforementioned lower gap is characterized by being either an opening provided in a part of the lower part of the precast concrete slab, or an opening between a plurality of bolts protruding from the lower part of the precast concrete slab.

[0032] According to this embodiment, the lower gap of the reinforced precast concrete slab is an opening provided in a part of its lower section or an opening between multiple bolts protruding from below, allowing the reinforcement bars for the pressure-resistant slab to be smoothly arranged using the opening.

[0033] Furthermore, in another embodiment of the construction method for the foundation structure according to the present invention, In the aforementioned process of installing reinforced precast concrete slabs, the pair of precast concrete slabs are connected with a connecting material. The concrete pouring process is characterized by connecting the pair of reinforced precast concrete panels and other structures to each other via bracing members prior to the concrete pouring.

[0034] According to this embodiment, by connecting a pair of precast concrete slabs with a connecting member, it is possible to maintain a position with a gap of a desired width between them. Furthermore, by connecting a pair of reinforced precast concrete slabs and other structures via bracing members prior to concrete pouring, it is possible to suppress the movement or displacement of the pair of reinforced precast concrete slabs due to the pressure acting during concrete pouring.

[0035] Furthermore, in another embodiment of the construction method for the foundation structure according to the present invention, The connecting member is formed from a rod having one male thread and one female thread at each end, and a pair of cylindrical members having a female thread that screws into the male thread or the female thread, and the other male thread, and a flange, the flanges being configured to engage with the outer surface of the precast concrete slab. The pair of reinforced precast concrete panels are provided with through holes at corresponding positions through which the cylindrical material is inserted. The concrete pouring process is characterized by removing the cylindrical member from the rod member after concrete pouring, and filling the through-hole formed when the cylindrical member is removed with a filler material.

[0036] According to this embodiment, the connecting member is formed from a rod having one male thread and one female thread at each end, and a pair of cylindrical members having a female thread that screws into the male thread or the female thread, the other male thread, and a flange, so that the flange engages with the outer surface of the precast concrete slab. This allows the pair of precast concrete slabs to be firmly fixed together when pouring concrete into a gap of a desired width, and after concrete pouring, the cylindrical members can be quickly rotated and removed from both ends of the rod. Furthermore, by filling the through-holes created by removing the cylindrical members with a filler material, it is possible to prevent rainwater and groundwater from seeping into the interior of the foundation beam through the through-holes.

[0037] Furthermore, one embodiment of the half-precast beam according to the present invention is: A half-precast beam that forms the foundation beam, The present invention is characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with the corresponding portions of the reinforcement bars of both slabs crossing each other. At least one of the upper or lower main bars is connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, and a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab, with the lower part of each reinforcing bar protruding below the precast concrete slab.

[0038] According to this embodiment, a portion of a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, is embedded at intervals along the longitudinal direction of the precast concrete slab, and the lower part of each reinforcing bar protrudes below the precast concrete slab. A post-construction concrete body is formed in the gap between a pair of reinforced precast concrete slabs, and the lower part of each reinforcing bar protrudes below the precast concrete slab, so as not to interfere with each reinforcing bar. This makes it possible to prevent interference between the precast concrete slab and the reinforcing bars for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and forming a foundation structure in which the cross-section of the pressure slab can be effectively incorporated into the cross-section of the foundation beam.

[0039] Furthermore, other embodiments of the half-precast beam according to the present invention include: A half-precast beam that forms the foundation beam, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. The present invention is characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with the corresponding longitudinal bars of the reinforcing bars tied or welded to the corrugated reinforcing bars or longitudinal bars of each of the aforementioned separate reinforcing bars, and the lower part of each reinforcing bar protrudes below the precast concrete slab, such that the corresponding portions of the reinforcing bars of both slabs intersect.

[0040] According to this embodiment, a plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars (truss bars) extending in the longitudinal direction and exhibiting a corrugated shape, are used. The separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, are connected to the separate reinforcing bars. The lower part of each reinforcing bar protrudes below the precast concrete slab. A post-construction concrete body is formed in the gap between a pair of reinforced precast concrete slabs. This allows the reinforcement bars for the pressure slab to be placed below each reinforcing bar that protrudes below the precast concrete slab, without interfering with each of the reinforcing bars. This prevents interference between the precast concrete slab and the reinforcement bars for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and creating a foundation structure in which the cross-section of the pressure slab can be effectively incorporated into the cross-section of the foundation beam.

[0041] Furthermore, other embodiments of the half-precast beam according to the present invention include: A half-precast beam that forms the foundation beam, A pair of reinforced precast concrete slabs is characterized in that at least one of the upper or lower main reinforcing bars is connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab, the precast concrete slab is provided with multiple support legs below it, a lower gap is provided between adjacent support legs, and the lower part of each reinforcing bar is located in the lower gap, with a post-construction concrete body formed between the two slabs in which portions of the corresponding reinforcing bars intersect.

[0042] According to this embodiment, a portion of a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, is embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of support legs are provided below it, with a lower gap between adjacent support legs, and the lower part of each reinforcing bar is located in the lower gap. A post-construction concrete body is formed in the gap between a pair of reinforced precast concrete slabs, and the reinforcing bars for the pressure slab can be arranged below each reinforcing bar located in the lower gap between the support legs without interfering with each reinforcing bar. This prevents interference between the precast concrete slab and the reinforcing bars for the foundation beam, and allows the beam depth of the foundation beam to be viewed from a position below the pressure slab, thereby forming a foundation structure in which the cross-section of the pressure slab can be effectively incorporated into the cross-section of the foundation beam.

[0043] Furthermore, other embodiments of the half-precast beam according to the present invention include: A half-precast beam that forms the foundation beam, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. The present invention is characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with a portion of the corresponding reinforcement bars intersecting each other. The corrugated reinforcement bars or the longitudinal bars of the respective separate reinforcement bars are tied or welded to the longitudinal bars of the corresponding reinforcement bars of the separate reinforcement bars, and the precast concrete slab is provided with a plurality of support legs below it, with a lower gap provided between adjacent support legs, and the lower part of each reinforcement bar located in the lower gap.

[0044] According to this embodiment, a plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars (truss bars) extending in the longitudinal direction and exhibiting a corrugated shape, are provided. The separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, are connected to the separate reinforcing bars. A plurality of support legs are provided below, with a lower gap between adjacent support legs, and the lower part of each reinforcing bar is located in the lower gap. A post-construction concrete body is formed in the gap between a pair of reinforced precast concrete slabs, allowing the reinforcement for the pressure slab to be placed below each reinforcing bar located in the lower gap between the support legs without interfering with each reinforcing bar. This prevents interference between the precast concrete slab and the reinforcement for the foundation beam, while allowing the beam depth of the foundation beam to be viewed from a position below the pressure slab, and forming a foundation structure that effectively incorporates the cross-section of the pressure slab into the cross-section of the foundation beam.

[0045] Furthermore, one embodiment of the foundation structure according to the present invention is: A foundation structure comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The lower parts of the multiple support legs for leveling are embedded in the lean concrete at intervals along the longitudinal direction of the foundation beam, and the multiple support legs are arranged at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcing bars, and a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab, with the lower part of each reinforcing bar protruding below the precast concrete slab. A pair of reinforced precast concrete slabs are formed with the corresponding portions of their reinforcing bars crossing each other, and a post-construction concrete body is formed between them to form a foundation beam, which is a half-precast beam. The pressure-resistant slab is characterized in that, within the height range of the support legs, reinforcing bars for the pressure-resistant slab are arranged, and a concrete body for the pressure-resistant slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming the pressure-resistant slab.

[0046] According to this embodiment, a foundation beam, which is a half-precast beam, is formed by a pair of reinforced precast concrete slabs, to which at least one of the upper or lower main reinforcements is connected, and a portion of a plurality of roughly U-shaped or roughly L-shaped reinforcing bars is embedded at intervals in the longitudinal direction of the precast concrete slab, with the lower part of each reinforcing bar protruding below the precast concrete slab, and a post-constructed concrete body is formed between the two slabs with the corresponding portions of the reinforcing bars of the two slabs crossing each other. The pressure plate is formed by the pressure plate reinforcement bars arranged within the height range of a plurality of support legs for level adjustment below the foundation beam and the pressure plate concrete body embedded below each reinforcing bar, thereby preventing interference between the precast concrete slab and the foundation beam reinforcement bars, allowing the beam depth of the foundation beam to be viewed from a position below the pressure plate, and forming a foundation structure that effectively incorporates the cross-section of the pressure plate into the cross-section of the foundation beam.

[0047] Furthermore, other embodiments of the foundation structure according to the present invention are: A foundation structure comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The lower parts of the multiple support legs for leveling are embedded in the lean concrete at intervals along the longitudinal direction of the foundation beam, and the multiple support legs are arranged at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. In a pair of precast concrete slabs with reinforced bars, the corresponding longitudinal bars of the reinforcing bars are tied or welded to the corrugated reinforcing bars or longitudinal bars of each of the aforementioned separate reinforcing bars, and the lower part of each reinforcing bar protrudes below the precast concrete slab. A post-construction concrete body is formed between the two slabs, with portions of the corresponding reinforcing bars of both slabs crossing each other, to form a foundation beam which is a half-precast beam. The pressure-resistant slab is characterized in that, within the height range of the support legs, reinforcing bars for the pressure-resistant slab are arranged, and a concrete body for the pressure-resistant slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming the pressure-resistant slab.

[0048] According to this embodiment, a pair of reinforced precast concrete slabs, each comprising one or two separate longitudinal bars and wavy reinforcing bars (truss bars) extending in the longitudinal direction, are configured such that the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, are connected to the separate reinforcement bars, with the lower part of each reinforcing bar protruding below the precast concrete slab, and the two corresponding reinforcing bars are part of the precast concrete slab. With the beams intersecting, a post-construction concrete body is formed between them to create a foundation beam, which is a half-precast beam. The pressure slab is formed by the pressure slab reinforcement bars placed within the height range of multiple support legs for level adjustment below the foundation beam, and the pressure slab concrete body embedded below each reinforcement bar. This prevents interference between the precast concrete slab and the foundation beam reinforcement bars, while allowing the beam depth of the foundation beam to be viewed from below the pressure slab, and creating a foundation structure in which the cross-section of the pressure slab can be effectively incorporated into the cross-section of the foundation beam.

[0049] Furthermore, by embedding the entire roughly U-shaped or L-shaped reinforcing bar, which is tied or otherwise secured to the precast concrete slab, into the post-construction concrete body, the shear reinforcement effect can be enhanced. As a result, even if the degree of integration between the precast concrete slab and the post-construction concrete body is not good, a high shear reinforcement effect can be achieved by the roughly U-shaped or L-shaped reinforcing bar.

[0050] Furthermore, when constructing a post-construction concrete body, the vertical reinforcement, separate vertical reinforcement, and the corrugated reinforcement between them can resist the pressure acting on the inside of the precast concrete slab when concrete for the foundation beam is poured, as well as the earth pressure acting on the outside of the precast concrete slab when soil is backfilled before the concrete for the foundation beam is poured, in a mechanism similar to that of a truss beam.

[0051] Furthermore, other embodiments of the foundation structure according to the present invention are: A foundation structure comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcing bars, and a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab. The precast concrete slab is provided with multiple support legs below it, the lower part of each support leg is fitted into a recess on the upper surface of the lean concrete, and a lower gap is provided between adjacent support legs, with the lower part of each reinforcing bar located in this lower gap. A pair of reinforced precast concrete slabs are arranged with portions of their corresponding reinforcing bars crossing each other, and a post-construction concrete body is formed between them to form a foundation beam, which is a half-precast beam. The pressure-resistant slab is characterized in that, within the height range of the lower gap, reinforcing bars for the pressure-resistant slab are arranged, and a concrete body for the pressure-resistant slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming the pressure-resistant slab.

[0052] According to this embodiment, a foundation beam, which is a half-precast beam, is formed by a pair of reinforced precast concrete slabs, each to which at least one of the upper or lower main reinforcements is connected, and to which a portion of a plurality of roughly U-shaped or roughly L-shaped reinforcing bars are embedded at intervals in the longitudinal direction of the precast concrete slab, with the corresponding portions of the reinforcing bars of both slabs intersecting, and a post-constructed concrete body is formed between them. A pressure plate is formed by the pressure plate reinforcement bars arranged below the foundation beam within the height range of the lower gap between the plurality of support legs of the precast concrete slab, and the pressure plate concrete body embedded below each reinforcement bar. This prevents interference between the precast concrete slab and the foundation beam reinforcement bars, allows the beam depth of the foundation beam to be viewed from a position below the pressure plate, and forms a foundation structure that effectively incorporates the cross-section of the pressure plate into the cross-section of the foundation beam.

[0053] Furthermore, other embodiments of the foundation structure according to the present invention are: A foundation structure comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. Each of the aforementioned separate reinforcing bars has its corresponding longitudinal reinforcing bars tied or welded to the corrugated reinforcing bars or longitudinal reinforcing bars of the respective separate reinforcing bars, and the precast concrete slab is provided with a plurality of support legs below it, the lower part of which is fitted into a recess on the upper surface of the lean concrete, and a lower gap is provided between adjacent support legs, with the lower part of each reinforcing bar located in this lower gap, and a post-construction concrete body is formed between the two, forming a foundation beam which is a half-precast beam, with some of the corresponding reinforcing bars of both slabs crossing each other. The pressure-resistant slab is characterized in that, within the height range of the lower gap, reinforcing bars for the pressure-resistant slab are arranged, and a concrete body for the pressure-resistant slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming the pressure-resistant slab.

[0054] According to this embodiment, a pair of reinforced precast concrete slabs is provided with one or two separate longitudinal bars and corrugated reinforcing bars (truss bars) that extend in the longitudinal direction and exhibit a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab, and a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, to which at least one of the upper or lower main bars is connected, are connected to the separate reinforcing bars, and a plurality of support legs are provided below them, with a lower gap provided between adjacent support legs, and the lower part of each reinforcing bar is located in the lower gap, and one of the corresponding reinforcing bars of the pair of reinforced precast concrete slabs is provided. With the sections intersecting, a post-construction concrete body is formed between them to create a foundation beam, which is a half-precast beam. Below the foundation beam, the pressure slab is formed by the pressure slab reinforcement bars placed within the height range of the lower gap between the multiple support legs of the precast concrete slab, and the pressure slab concrete body embedded below each reinforcement bar. This prevents interference between the precast concrete slab and the foundation beam reinforcement bars, allows the beam depth of the foundation beam to be viewed from below the pressure slab, and creates a foundation structure in which the cross-section of the pressure slab can be effectively incorporated into the cross-section of the foundation beam.

[0055] Furthermore, in other embodiments of the foundation structure according to the present invention, Through holes are provided at corresponding positions in the pair of reinforced precast concrete panels. Both ends of a connecting material, which will be embedded in the post-construction concrete body, extend from the through-holes in each of the pair of precast concrete panels. Each of the aforementioned through holes is characterized by being filled with a filler material.

[0056] According to this embodiment, when a pair of reinforced precast concrete slabs are constructed, the ends of the connecting material that will be embedded in the post-construction concrete body extend into the corresponding through-holes provided in the pair of reinforced precast concrete slabs, and the through-holes are filled with a filler material. This prevents rainwater, groundwater, etc. from entering the interior through the through-holes. [Effects of the Invention]

[0057] As can be understood from the above explanation, according to the foundation structure, construction method and half-precast beam of the present invention, in a foundation structure having a foundation beam consisting of a half-precast beam equipped with a precast concrete slab and a pressure-resistant slab, interference between the precast concrete slab and the reinforcing bars for the foundation beam can be prevented, the beam depth of the foundation beam can be viewed from a position below the pressure-resistant slab, and the cross-section of the pressure-resistant slab can be effectively incorporated into the cross-section of the foundation beam. [Brief explanation of the drawing]

[0058] [Figure 1] This is a perspective view diagram of an example of a construction method for a foundation structure according to an embodiment, showing a pair of reinforced precast concrete slabs placed on two rows of support legs, with reinforcement bars for the pressure-resistant slab arranged in the gap below. [Figure 2A] This diagram shows the process of forming the state shown in Figure 1, specifically the placement of reinforced precast concrete slabs on the rows of support legs. It is a longitudinal cross-sectional view taken in a direction perpendicular to the longitudinal direction of the foundation beam. [Figure 2B] Following Figure 2A, this is a process diagram showing the state in which the state of Figure 1 is formed, and it shows the state in which a reinforced precast concrete slab is placed on the row of support legs. It is a longitudinal cross-section taken in a direction perpendicular to the longitudinal direction of the foundation beam. [Figure 2C]Following Figure 2B, this is a process diagram showing the state in which the condition in Figure 1 is formed, with a pair of reinforced precast concrete slabs placed on two rows of support legs, and is a longitudinal cross-section taken in a direction perpendicular to the longitudinal direction of the foundation beam. [Figure 2D] Following Figure 2C, this is a process diagram showing the state in which the condition of Figure 1 is formed, with the reinforcement bars for the pressure plate placed in the lower gap. It is a longitudinal cross-section taken in a direction perpendicular to the longitudinal direction of the foundation beam. [Figure 2E] This figure corresponds to Figure 2C and shows another example of a pair of reinforced precast concrete panels. [Figure 3] Figure 2D follows a perspective view of a process diagram showing an example of a construction method for a foundation structure according to the embodiment, with a balance taken up by other structures. [Figure 4] This is a view from the direction of arrow IV in Figure 3, showing the state after concrete for the pressure slab has been poured from the state shown in Figure 3. [Figure 5] Figure 4 is a process diagram of an example of a construction method for a foundation structure according to the embodiment, showing an example of a foundation structure according to the embodiment in which post-cast concrete is poured into the gap between a pair of reinforced precast concrete slabs. [Figure 6A] This diagram shows other support structures for a pair of reinforced precast concrete slabs. [Figure 6B] This is a perspective view of the concrete block applied to the support structure in Figure 6A. [Figure 7] This figure shows another example of a foundation structure according to the embodiment. [Figure 8] This figure shows yet another example of the foundation structure according to the embodiment. [Modes for carrying out the invention]

[0059] The following describes a foundation structure according to an embodiment, its construction method, and an example of a half-precast beam, with reference to the attached drawings. Note that in this specification and the drawings, substantially identical components are denoted by the same reference numerals to avoid redundant explanations.

[0060] [Foundation structure according to an embodiment, its construction method, and half-precast beam] Referring to Figures 1 to 8, a foundation structure according to an embodiment, its construction method, and an example of a half-precast beam will be described.

[0061] Here, Figures 1 to 5 are, in order, process diagrams of an example of a construction method for a foundation structure according to the embodiment. Figure 1 is a perspective view showing a state in which a pair of reinforced precast concrete slabs are placed on two rows of support legs, and reinforcement bars for the pressure slab are arranged in the gap below. Figures 2A to 2D are, in order, process diagrams that form the state shown in Figure 1. Figure 3 is a perspective view following Figure 2D, showing a state in which the foundation structure is braced against other structures. Figure 4 is a view from arrow IV in Figure 3, showing the state in which the pressure slab concrete has been poured from the state shown in Figure 3. Figure 5 is a process diagram following Figure 4, showing an example of a foundation structure according to the embodiment, and also showing an example of the foundation structure according to the embodiment.

[0062] As shown in Figure 1, on the lean concrete C at the construction site, two rows of support legs 60A are installed at intervals, each consisting of multiple support legs 60 (two in the illustrated example) aligned with the longitudinal direction of the half-precast beam to be constructed (support leg installation process).

[0063] Next, a pair of reinforced precast concrete slabs 50 are placed and fixed on the corresponding support leg rows 60A with a gap S1 between them, and lateral support members 77 are installed across the side surfaces 22 of the precast concrete slabs 20 forming the reinforced precast concrete slabs 50 and the lean concrete C to maintain the upright position of the pair of reinforced precast concrete slabs 50 (reinforced precast concrete slab installation process).

[0064] As shown in Figure 2A, a nut 61 is embedded in the lean concrete C, the lower part of an insert 62 is fitted into the nut 61 so as not to rotate relative to it, and the lower part of a bolt 63, which has a male thread 63a on its outer circumference and a two-tiered head 64 at its top, is screwed into the female thread 62a of the insert 62, thereby forming a support leg 60 for leveling the reinforced precast concrete slab 50.

[0065] A horizontal member 65 is placed across the heads 64 of both corresponding support legs 60 located in the width direction of the half-precast beam. A leg fixing member 66, formed from a shaped steel (angle steel in the illustrated example), is installed on the horizontal member 65, and the legs of the reinforced precast concrete slab 50 (or precast concrete slab 20) are lowered in the X1 direction and placed on the heads 64 of the support legs 60.

[0066] Next, the legs of the precast concrete slab 20, which are placed on the head 64 of the support legs 60, and the leg fixing members 66 are fixed using a fixing jig 67 such as a vise.

[0067] After fixing the legs of the precast concrete slab 20 and the leg fixing members 66, the lateral support members 77 are installed extending from the side 22 of the precast concrete slab 20 to the lean concrete C, thereby maintaining the upright position of the reinforced precast concrete slab 50 that is placed and fixed on the support leg row 60A.

[0068] Similarly, a reinforced precast concrete slab 50 is placed and fixed on the other support leg row 60A, thereby forming the state shown in Figure 2C. As shown in Figure 2C, when constructing the lean concrete C, the lean concrete C is constructed after laying the crushed stone G. The nuts 61 and inserts 62 are fixed to the lean concrete C by either drilling after the lean concrete C is constructed and installing the nuts 61 with the inserts 62 attached into the drilled holes, or by placing the nuts 61 with the inserts 62 attached onto the top surface of the crushed stone G and then constructing the lean concrete C so as to wrap around them.

[0069] Here, we will explain the reinforced precast concrete slab 50 in detail, referring to Figures 1 and 2C.

[0070] In the reinforced precast concrete slab 50, each of the two separate longitudinal bars 11A that extend in the longitudinal direction and to which a wavy reinforcing bar 17 (truss bar) that extends in the longitudinal direction and is sandwiched between the two separate longitudinal bars 11A and connected to both sides is a wavy reinforcing bar 17 (truss bar) that extends in the longitudinal direction and is connected to both sides is one of the two separate longitudinal bars 10A that are embedded at intervals in the longitudinal direction of the precast concrete slab 20, and each of the longitudinal bars 11 of the reinforcing bar 10 which is roughly U-shaped (roughly C-shaped) is connected to the other separate longitudinal bar 11A by binding or welding.

[0071] The reinforcing bar 10 consists of a longitudinal bar 11, an upper transverse bar 12 that bends at the upper end of the longitudinal bar 11 and extends laterally, an upper hook 13 that bends at the end of the upper transverse bar 12 and extends downward, a lower transverse bar 14 that bends at the lower end of the longitudinal bar 11 and extends laterally, and a lower hook 15 that bends at the end of the lower transverse bar 14 and extends upward, forming a roughly U-shape. In the illustrated example, both the upper hook 13 and the lower hook 15 are 90-degree hooks.

[0072] Here, the separate reinforcing bar 10A in the illustrated example is a unit consisting of two separate longitudinal bars 11A and a corrugated reinforcing bar 17, but it may also be a unit consisting of one separate longitudinal bar 11A and a corrugated reinforcing bar 17 embedded in the precast concrete slab 20. Furthermore, although the illustrated example includes a separate reinforcing bar 10A, the separate reinforcing bar 10A may be omitted, and the longitudinal bars 11 of the reinforcing bar 10 may be directly embedded in the precast concrete slab 20. In addition, although the reinforcing bar 10 in the illustrated example is roughly U-shaped, a reinforcing bar that is roughly L-shaped (not shown) may also be used.

[0073] Multiple separate vertical reinforcements 11A and a portion of the corrugated reinforcement bars 17 are embedded in the precast concrete slab 20, thereby attaching multiple separate reinforcement bars 10A to the precast concrete slab 20, and a corresponding reinforcement bar 10 is attached to each separate reinforcement bar 10A. In this attachment position, the lower part of the reinforcement bar 10 protrudes below the precast concrete slab 20.

[0074] Here, although not shown in the diagram, the thickness of the precast concrete slab may be increased, and a portion of the upper and lower main reinforcement bars (for example, one of each) may be embedded inside the precast concrete slab. In the form with a thicker precast concrete slab, it is preferable that, in addition to the vertical reinforcement bars 11, a portion of the upper main reinforcement bars 30 and lower main reinforcement bars 40 are further embedded, thereby suppressing cracking of the precast concrete slab that constitutes the reinforced precast concrete slab before the half-precast beam is manufactured.

[0075] Furthermore, although not shown in the diagram, there may be a configuration in which a reinforcing bar 10 is placed between a reinforcing bar 10 connected to another reinforcing bar 10A, and there is no other reinforcing bar 10A present. For example, in addition to the reinforcing bars 10 connected to another reinforcing bar 10A, there may be reinforcing bars 10 that are not connected to another reinforcing bar 10A.

[0076] In other words, any number of the reinforcing bars 10 that make up the reinforced precast concrete slab 50 shown in Figure 1 may be replaced with reinforcing bars 10 that are connected to other reinforcing bars 10A. In this way, by combining reinforcing bars 10 for which there are no corresponding other reinforcing bars 10A, it is possible to arrange a number of reinforcing bars 10 that can achieve the desired shear reinforcement effect.

[0077] Multiple upper main reinforcement bars 30 extending in the longitudinal direction are attached below multiple upper transverse reinforcement bars 12, and multiple lower main reinforcement bars 40 extending in the longitudinal direction are attached above multiple lower transverse reinforcement bars 14. Multiple upper main reinforcement bars 30 and lower main reinforcement bars 40 are attached to a precast concrete slab 20 to which multiple reinforcing bars 10 are attached, and the lower part of the reinforcing bars 10 protrudes below the precast concrete slab 20, forming a reinforced precast concrete slab 50.

[0078] For example, in Figure 2C, if the left reinforced precast concrete slab 50 is installed first and the right reinforced precast concrete slab 50 is installed later, the left reinforced precast concrete slab 50, which is installed first, has four upper main reinforcement bars 30 attached to multiple upper horizontal bars 12 at equal or approximately equal intervals in the horizontal direction, and three lower main reinforcement bars 40 attached to multiple lower horizontal bars 14 at equal or approximately equal intervals in the horizontal direction.

[0079] On the other hand, the right-side reinforced precast concrete slab 50, which is installed later, has three upper main reinforcement bars 30 attached to multiple upper horizontal bars 12 at equal or approximately equal intervals in the horizontal direction, and four lower main reinforcement bars 40 attached to multiple lower horizontal bars 14 at equal or approximately equal intervals in the horizontal direction.

[0080] In a pair of reinforced precast concrete slabs 50, one upper main reinforcement bar 30 is placed between the upper hooks 13 of both slabs 13, and one lower main reinforcement bar 40 is placed between the lower hooks 15 of both slabs 15, so that the reinforcing bars 10 of both slabs 50 do not interfere with each other at the overlapping position of the upper main reinforcement bars 30 and the lower main reinforcement bars 40 do not interfere with each other at the overlapping position of the reinforced precast concrete slabs 50. In this case, the installation of the upper main reinforcement bars 30 and lower main reinforcement bars 40 at the overlapping position of one of the reinforced precast concrete slabs 50 is omitted (in the illustrated example, one upper main reinforcement bar 30 and one lower main reinforcement bar 40 are each omitted).

[0081] The entire reinforced precast concrete slab 50 shown in the illustration may be manufactured in a factory or the like, transported to the site, and installed in the designated location. Alternatively, the precast concrete slab 20, the upper main reinforcement 30, and the lower main reinforcement 40 may be transported to the site without the upper main reinforcement 30 and lower main reinforcement 40 attached (all parts except the upper main reinforcement 30 and lower main reinforcement 40 may be manufactured in a factory or the like), and after the precast concrete slab 20 is installed in the designated location at the site, the upper main reinforcement 30 and lower main reinforcement 40 may be attached to form the reinforced precast concrete slab 50.

[0082] For example, the left-hand reinforced precast concrete slab 50 shown in Figure 2C is placed and fixed on the corresponding support leg row 60A, and then the right-hand reinforced precast concrete slab 50 is dropped from above and placed and fixed on the corresponding support leg row 60A.

[0083] By lowering the right-side reinforced precast concrete slab 50 downwards, the upper hook 13 is moved downwards so as to straddle one of the upper main reinforcement bars 30 at the overlapping position. By completely lowering the right-side reinforced precast concrete slab 50 and placing it in the corresponding support leg row 60A, multiple (seven in the illustrated example) upper main reinforcement bars 30 are arranged at equal or approximately equal intervals in the horizontal direction for both overlapping upper horizontal reinforcement bars 12, with the central upper main reinforcement bar 30 surrounded by the left and right upper hooks 13. Similarly, multiple (seven in the illustrated example) lower main reinforcement bars 40 are arranged at equal or approximately equal intervals in the horizontal direction for both overlapping lower horizontal reinforcement bars 14, with the central lower main reinforcement bar 40 surrounded by the left and right lower hooks 15, thus automatically arranging the reinforcement and forming a gap S1 between the pair of reinforced precast concrete slabs 50.

[0084] In this way, when a pair of reinforced precast concrete panels 50 are installed with a gap S1 between them, the beam reinforcement is placed at the same time, thus eliminating or reducing the labor required for beam reinforcement placement.

[0085] The precast concrete slab 20 has multiple (two in the illustrated example) through-pipes 27 (through-holes) embedded in its upper and lower sections, and both ends of the connecting material 70 are fixed to the corresponding through-holes 27 in a pair of precast concrete slabs 20.

[0086] The connecting member 70 is formed from a rod 71 having male threads at both ends and a pair of cylindrical members 73 having female threads inside that screw into the male threads and a flange 74. As shown in Figure 2C, both ends of the rod 71 are positioned in corresponding through holes 27, and the cylindrical members 73 are installed in the through holes 27 from the outside so that the female threads of the cylindrical members 73 are screwed into the male threads at the ends of the rod 71, thereby engaging the flange 74 with the side surface 22 (outer surface) of the precast concrete slab 20.

[0087] By fixing multiple connecting members 70 to a pair of precast concrete slabs 20, the pair of reinforced precast concrete slabs 50 can maintain a state in which there is a gap S1 of a predetermined width t1 between them.

[0088] Furthermore, the multiple connecting members 70 prevent the reinforced precast concrete slab 50 from being displaced or shifted by the lateral pressure of the concrete when concrete for the foundation beam is poured into the gap S1 during subsequent construction.

[0089] As shown in Figure 2D, the level of the pair of reinforced precast concrete slabs 50 is set to a predetermined level by raising and lowering the level adjustment bolt 63 in the X2 direction. Then, the pressure slab reinforcement 18 is placed in the lower gap S2 at a height t2 between the lower surface 23 of the precast concrete slab 20 and the upper surface C1 of the lean concrete C, thereby creating the state shown in Figures 1 and 2D. The pressure slab reinforcement 18 in the illustrated example is a double reinforcement with two intersecting reinforcements on the top and bottom (reinforcement placement process).

[0090] Here, as shown in Figure 2E, a precast concrete slab 50A with reinforced bars may be used, in which there are no separate reinforcing bars 10A, and the longitudinal bars 11 forming the reinforcing bars 10 are directly embedded in the precast concrete slab 20A.

[0091] The precast concrete slab 20A has a narrow leg 25 at its lower part, which is narrower than the rest of the slab via a stepped portion 26, and vertical reinforcement bars 11 protrude downward from the stepped portion 26.

[0092] Next, as shown in Figure 3, additional reinforcing bars T1 and T2 (an example of other structural elements) for the foundation beam are placed to connect to the half-precast beam formed by the installed pair of reinforced precast concrete slabs 50, and the pair of precast concrete slabs 20 and the other foundation beam reinforcing bars T1 and T2 are connected with multiple bracing members 78 to provide support.

[0093] Next, as shown in Figure 4, a pressure-resistant slab 80 is constructed by pouring concrete for the pressure-resistant slab into the lower gap S2 so as to embed the reinforcing bars 18 for the pressure-resistant slab, thereby creating a concrete body 81 for the pressure-resistant slab in which the reinforcing bars 18 are embedded.

[0094] Next, as shown in Figure 5, by pouring concrete for the foundation beam into the gap S1 between the pair of precast concrete slabs 20, a post-construction concrete body 85 is constructed in which separate reinforcing bars 10A and 10, upper main bars 30 and lower main bars 40, and connecting members 71 are embedded (concrete pouring process).

[0095] Subsequently, the cylindrical member 73, which is fitted into the through-hole 27 of the precast concrete slab 20 and screwed to the end of the rod member 71, is removed in the X5 direction while rotating it, and the through-hole 27 that was opened by removing the cylindrical member 73 is filled with a filler material 28, thereby constructing a foundation beam 100 which is a half-precast beam having a pair of reinforced precast concrete slabs 50 and a post-constructed concrete body 85.

[0096] Then, with the construction of the foundation beam 100, the foundation structure 200 is constructed, in which the pressure-resistant slab 80 and the foundation beam 100 are joined.

[0097] In the construction method shown in the illustration, the precast concrete slab 20 functions as formwork (side frame) when forming the post-construction concrete body 85, while remaining as a component of the half-precast beam 100. This eliminates the need for setting up and removing the side frame, thus saving labor in setting up and removing the formwork.

[0098] Thus, this construction method for foundation structures using a pair of reinforced precast concrete slabs 50 allows for labor savings in formwork installation and removal, while eliminating or reducing the labor required for beam reinforcement work. This method offers superior beam manufacturability (or constructability) and improves overall quality.

[0099] Furthermore, by placing a reinforced precast concrete slab 50 on top of the support leg row 60A and arranging the reinforcement bars 18 for the pressure slab in the lower gap S2 within the height range of the support leg row 60A, it is possible to construct a foundation structure 200 in which the pressure slab 80 and the foundation beam 100 are joined, while preventing interference between the precast concrete slab and the reinforcement bars that would prevent reinforcement from being placed when, for example, the lower end of the precast concrete slab is directly installed on the construction surface and the reinforcement bars for the pressure slab are placed. In addition, the beam depth of the foundation beam 100 can be viewed from a position below the pressure slab 80, and the cross-section of the pressure slab 80 can be effectively incorporated into the cross-section of the foundation beam 100.

[0100] Furthermore, since the entire reinforcing bar 10, which is roughly U-shaped and bound together with the separate reinforcing bars 10A that have separate vertical bars 11A embedded in the precast concrete slab 20, is embedded in the post-construction concrete body 85, the shear reinforcement effect of the reinforcing bar 10 can be enhanced. As a result, even if the degree of integration between the precast concrete slab 20 and the post-construction concrete body 85 is not good, a high shear reinforcement effect can be achieved by the roughly U-shaped reinforcing bar 10.

[0101] Furthermore, the vertical reinforcement bars 11 of the roughly U-shaped reinforcing bars 10 and the separate vertical reinforcement bars 11A of the separate reinforcing bars 10A are connected to the wavy reinforcing bars 17 that extend vertically and exhibit a wave-like shape, thereby enabling a stronger integration of the two. In addition, with this configuration, the vertical reinforcement bars 11, the separate vertical reinforcement bars 11A, and the wavy reinforcing bars 17 between them can resist, in a mechanism similar to that of a truss beam, the pressure acting on the inside of the precast concrete slab 20 when concrete is poured during the construction of the post-construction concrete body 85, and the earth pressure acting on the outside of the precast concrete slab 20 when soil is backfilled before concrete is poured.

[0102] Next, other support structures for reinforced precast concrete slabs will be described with reference to Figures 6A and 6B. Here, Figure 6A is a diagram showing a pair of other support structures for reinforced precast concrete slabs, and Figure 6B is a perspective view of a concrete block applied to the support structure in Figure 6A.

[0103] The support structure for the reinforced precast concrete slab shown in the illustrated example differs from the support legs 60 and support leg rows 60A shown in Figure 2A, etc., in that the support legs 90 for leveling are concrete blocks equipped with two engaging keys 94 and 96 on their upper surfaces 92 that sandwich and fix the legs of the reinforced precast concrete slab 50.

[0104] A concrete engaging projection 94 (an example of an engaging key) is similarly provided on the upper surface 92 of the concrete block 90. ​​After the legs of the precast concrete slab 20 are placed on the upper surface 92, a leg fixing member 96 (another example of an engaging key) made of shaped steel (angle steel in the illustrated example) is installed so as to sandwich the legs together with the engaging projection 94.

[0105] The height level of the top surface 92 of the concrete block 90 is adjusted so that the reinforced precast concrete slab 50 can be installed at the predetermined installation level once the concrete block 90 is placed on the top surface of the lean concrete C.

[0106] As shown in the illustrated example, by using a concrete block 90 equipped with engaging keys 94 and 96 on its upper surface 92 for fixing the legs of the reinforced precast concrete slab 50, the reinforced precast concrete slab 50 can be placed in a stable position on the heavy concrete block 90, and its installation level can be adjusted as desired.

[0107] Next, with reference to Figures 7 and 8, other examples of the foundation structure according to the embodiment will be described.

[0108] The foundation structure 200A shown in Figure 7 differs from the configuration shown in Figure 2C, etc., which has support legs 60 and rows of support legs 60A and a reinforced precast concrete slab 50, in that the precast concrete slab 20B forming the reinforced precast concrete slab 50B has a plurality of precast concrete support legs 28 below it, an opening S2 is provided between the plurality of support legs 28, and the lower part of the support legs 28 is fitted into a recess C2 on the upper surface of the lean concrete C.

[0109] The lower opening S2 has the lower parts of several reinforcing bars (not shown) located below it, and pressure slab reinforcement bars 18 are placed between the lower parts of each reinforcing bar. Pressure slab 80 is formed by constructing a pressure slab concrete body 81 in which each reinforcing bar and pressure slab reinforcement bars 18 are embedded in the lower opening S2, and a pressure slab 80 is formed by constructing a post-construction concrete body 85 in the gap S1 between a pair of precast concrete slabs 20B to construct a half-precast beam, the foundation beam 100A, and the foundation structure 200A formed by the pressure slab 80 and the foundation beam 100A is constructed.

[0110] On the other hand, the foundation structure 200B shown in Figure 8 differs from the foundation structure 200A shown in Figure 7 in that the reinforced precast concrete slab 50 is equipped with support legs 68 made of bolts or the like below it, a lower gap S2 which is an opening is provided between the multiple support legs 28, and a fitting body 69 at the lower end of the support leg 68 is fitted into a recess C2 on the upper surface of the lean concrete C.

[0111] As shown in Figures 7 and 8, the reinforced precast concrete slab may be equipped with support legs made of precast concrete, or with support legs made of steel such as bolts. In either case, when the support legs are installed in the recess C2 of the lean concrete C, a lower gap S2 is formed, which is an opening of a predetermined height t2. With the reinforced precast concrete slabs 50 and 50A installed at a predetermined level, the reinforcement bars 18 for the pressure slab are placed in the lower gap S2, and the pressure slab 80 is constructed.

[0112] Other embodiments may be used in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited in any way to the configurations shown herein. In this regard, modifications can be made without departing from the spirit of the present invention, and can be appropriately determined according to the application form. [Explanation of symbols]

[0113] 10: Reinforcement muscles 10A: Additional reinforcing bars 11: Vertical lines 11A: Separate vertical reinforcement 12: Superior transverse muscle 13: Upper hook (90-degree hook) 14: Lower transverse muscle 15: Lower hook (90-degree hook) 17: Wavy reinforcing muscle 18: Reinforcement bars for pressure-resistant slabs 20, 20A, 20B: Precast concrete slab 22: Side (outer surface) 23: Bottom surface 25: Narrow legs 26: Stepped section 27: Through hole (through pipe) 28:Support leg 30: Top main reinforcement 40: Bottom main reinforcement 50, 50A, 50B: Reinforced precast concrete panels 60: Support legs (support legs for leveling) 60A: Support leg row 61: Nut 62: Insert 62a: Female thread 63: Bolt 63a: Male screw 64:Head 65: Horizontal structural members 66: Leg fixing material 67: Fixing jig 68:Support leg 69: Trapped 70: Connecting material 71: Bar material 73: Tube material 74: Flange 77: Lateral support material 78: Support material 80: Pressure-resistant plate 81: Concrete body for pressure-resistant slab 85: Post-construction concrete body 90: Concrete blocks (support legs for leveling) 92:Top surface (top) 94: Engaging projection (engaging key) 96: Leg fixing material (engaging key) 100: Half-precast beam 200,200A,200B:Foundation structure S1: Gap S2: Lower gap C: Discarded Concrete C1:Top surface C2: Recess G: Crushed stone T1, T2: Other structural elements (reinforcement bars for other foundation beams)

Claims

1. A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The support leg installation step involves arranging the support legs at intervals along the longitudinal direction of the foundation beam, with the lower parts of the support legs for leveling embedded in the lean concrete, and arranging the support legs at intervals along the width direction of the foundation beam to form two rows of support legs. A precast concrete slab with reinforced steel is installed by placing and fixing a pair of precast concrete slabs with reinforced steel, each of which has at least one of its upper or lower main reinforcement bars connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, with a portion of each reinforcing bar embedded at intervals along the longitudinal direction of the precast concrete slab, and the lower part of each reinforcing bar protruding below the precast concrete slab, on the two rows of support legs, with the corresponding portions of the reinforcing bars of the two slabs crossing each other and a gap between them. The reinforcement process involves arranging reinforcing bars for the pressure-resistant plate within the height range of the support legs, A method for constructing a foundation structure, characterized by comprising a concrete pouring step, in which concrete for a pressure-resistant slab is poured so as to bury the lower part of the reinforcement bars for the pressure-resistant slab and each of the reinforcing bars, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure-resistant slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure-resistant slab and the foundation beams.

2. A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, The support leg installation step involves arranging the support legs at intervals along the longitudinal direction of the foundation beam, with the lower parts of the support legs for leveling embedded in the lean concrete, and arranging the support legs at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A precast concrete slab with reinforcement bars is installed, in which a pair of precast concrete slabs with reinforcement bars are placed and fixed on the two rows of support legs, with the corresponding longitudinal bars of the reinforcing bars tied or welded to the corrugated reinforcing bars or longitudinal bars of the respective separate reinforcing bars, and the lower part of each reinforcing bar protrudes below the precast concrete slab, such that the parts of the corresponding reinforcing bars of both slabs cross each other and a gap is left between them. The reinforcement process involves arranging reinforcing bars for the pressure-resistant plate within the height range of the support legs, A method for constructing a foundation structure, characterized by comprising a concrete pouring step, in which concrete for a pressure-resistant slab is poured so as to bury the lower part of the reinforcement bars for the pressure-resistant slab and each of the reinforcing bars, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure-resistant slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure-resistant slab and the foundation beams.

3. In the support leg installation process, a horizontal member is placed across the two rows of support legs, and a leg fixing member is installed on the horizontal member to fix the legs of the reinforced precast concrete slab. The method for constructing a foundation structure according to claim 1 or 2, characterized in that, in the step of installing the reinforced precast concrete slab, the legs of the reinforced precast concrete slab are fixed to the leg fixing material.

4. A method for constructing a foundation structure according to claim 1 or 2, characterized in that the support leg for leveling has an insert embedded in the lean concrete, a bolt with a male thread that is screwed into the female thread of the insert, and a nut into which the lower part of the insert is fitted and embedded in the lean concrete.

5. The method for constructing a foundation structure according to claim 1 or 2, characterized in that the support leg for leveling is a concrete block having an engaging key on its upper surface for fixing the leg portion of the reinforced precast concrete slab.

6. A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, A lean concrete layer with multiple recesses on its top surface is constructed. A precast concrete slab with reinforcement bars is installed by fitting the lower parts of the support legs into corresponding recesses, with the corresponding parts of the reinforcement bars of both slabs crossing each other and a gap between them, and the lower parts of the support legs fitting into corresponding recesses, wherein at least one of the upper or lower main reinforcement bars is connected to multiple roughly U-shaped or roughly L-shaped reinforcing bars, a portion of each reinforcement bar is embedded at intervals along the longitudinal direction of the precast concrete slab, the precast concrete slab is provided with multiple support legs below it, a lower gap is provided between adjacent support legs, and the lower part of each reinforcement bar is located in the lower gap, and the precast concrete slab with reinforcement bars of both slabs crossing each other and a gap is provided between them, and The reinforcement process involves placing reinforcing bars for the pressure-resistant plate within the height range of the aforementioned lower gap, A method for constructing a foundation structure, characterized by comprising a concrete pouring step, in which concrete for a pressure-resistant slab is poured so as to bury the lower part of the reinforcement bars for the pressure-resistant slab and each of the reinforcing bars, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure-resistant slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure-resistant slab and the foundation beams.

7. A method for constructing a foundation structure, comprising at least a pressure-resistant plate and a foundation beam erected from the pressure-resistant plate, A lean concrete layer with multiple recesses on its top surface is constructed. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A precast concrete slab with reinforcement is installed by fitting the lower parts of the support legs into the corresponding recesses, with the wavy reinforcement bars or longitudinal bars of each of the aforementioned separate reinforcing bars tied or welded to the corresponding longitudinal bars of the reinforcing bars, and the precast concrete slab having a plurality of support legs below it, with a lower gap provided between adjacent support legs, and the lower part of each reinforcement bar located in the lower gap, with the corresponding parts of the reinforcing bars of both slabs crossing each other and a gap provided between them, The reinforcement process involves placing reinforcing bars for the pressure-resistant plate within the height range of the aforementioned lower gap, A method for constructing a foundation structure, characterized by comprising a concrete pouring step, in which concrete for a pressure-resistant slab is poured so as to bury the lower part of the reinforcement bars for the pressure-resistant slab and each of the reinforcing bars, and concrete for the foundation beams is poured into the gaps, thereby constructing the pressure-resistant slab and the foundation beams which are half-precast beams, and constructing the foundation structure formed by the pressure-resistant slab and the foundation beams.

8. The method for constructing a foundation structure according to claim 6 or 7, characterized in that the lower gap is either an opening provided in a part of the lower part of the precast concrete slab, or an opening between a plurality of bolts protruding from the lower part of the precast concrete slab.

9. In the aforementioned process of installing reinforced precast concrete slabs, the pair of precast concrete slabs are connected with a connecting material. The method for constructing a foundation structure according to any one of claims 1, 2, 6, or 7, characterized in that, prior to the concrete pouring process, the pair of reinforced precast concrete slabs and other structures are connected to each other via bracing members.

10. The connecting member is formed from a rod having one male thread and one female thread at each end, and a pair of cylindrical members having a female thread that screws into the male thread or the female thread, and the other male thread, and a flange, the flanges being configured to engage with the outer surface of the precast concrete slab. The pair of reinforced precast concrete panels are provided with through holes at corresponding positions through which the cylindrical material is inserted. The method for constructing a foundation structure according to claim 9, characterized in that, in the concrete pouring step, the cylindrical member is removed from the rod member after concrete pouring, and the through-hole formed when the cylindrical member is removed is filled with a filler material.

11. A half-precast beam that forms the foundation beam, A half-precast beam characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with the corresponding portions of the reinforcement bars of both slabs crossing each other, and at least one of the upper or lower main bars being connected to a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, a portion of each reinforcing bar being embedded at intervals along the longitudinal direction of the precast concrete slab, and the lower part of each reinforcing bar protruding below the precast concrete slab.

12. A half-precast beam that forms the foundation beam, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A half-precast beam characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with the corresponding longitudinal bars of the reinforcing bars tied or welded to the corrugated reinforcing bars or longitudinal bars of each of the aforementioned separate reinforcing bars, and the lower part of each reinforcing bar protrudes below the precast concrete slab, such that the corresponding reinforcing bars of both slabs intersect with each other.

13. A half-precast beam that forms the foundation beam, A half-precast beam characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with the corresponding reinforcement bars of both slabs crossing each other, and at least one of the upper or lower main bars being connected to a plurality of roughly U-shaped or roughly L-shaped reinforcing bars, a portion of each reinforcing bar being embedded at intervals along the longitudinal direction of the precast concrete slab, the precast concrete slab having a plurality of support legs below it, a lower gap being provided between adjacent support legs, and the lower part of each reinforcing bar being located in the lower gap.

14. A half-precast beam that forms the foundation beam, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. A half-precast beam characterized in that a pair of reinforced precast concrete slabs are formed with a post-construction concrete body between them, with a portion of the corresponding reinforcement bars crossing each other, and the longitudinal bars of the reinforcing bars of the reinforcing bars of each of the aforementioned separate reinforcing bars being tied or welded to the corrugated reinforcing bars or the aforementioned separate longitudinal bars of each of the aforementioned separate reinforcing bars, the precast concrete slab having a plurality of support legs below it, a lower gap provided between adjacent support legs, and the lower part of each reinforcement bar located in the lower gap, the two precast concrete slabs having a portion of the corresponding reinforcement bars of each crossing each other.

15. A foundation structure comprising at least a pressure plate and a foundation beam erected from the pressure plate, The lower parts of the multiple support legs for leveling are embedded in the lean concrete at intervals along the longitudinal direction of the foundation beam, and the multiple support legs are arranged at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcing bars, and a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab, with the lower part of each reinforcing bar protruding below the precast concrete slab. A pair of reinforced precast concrete slabs are formed with the corresponding portions of their reinforcing bars crossing each other, and a post-construction concrete body is formed between them to form a foundation beam, which is a half-precast beam. A foundation structure characterized in that, within the height range of the support legs, reinforcing bars for the pressure slab are arranged, and a concrete body for the pressure slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming a pressure slab.

16. A foundation structure comprising at least a pressure plate and a foundation beam erected from the pressure plate, The lower parts of the multiple support legs for leveling are embedded in the lean concrete at intervals along the longitudinal direction of the foundation beam, and the multiple support legs are arranged at intervals along the width direction of the foundation beam to form two rows of support legs. Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. In a pair of precast concrete slabs with reinforced bars, the corresponding longitudinal bars of the reinforcing bars are tied or welded to the corrugated reinforcing bars or longitudinal bars of each of the aforementioned separate reinforcing bars, and the lower part of each reinforcing bar protrudes below the precast concrete slab. A post-construction concrete body is formed between the two slabs, with portions of the corresponding reinforcing bars of both slabs crossing each other, to form a foundation beam which is a half-precast beam. A foundation structure characterized in that, within the height range of the support legs, reinforcing bars for the pressure slab are arranged, and a concrete body for the pressure slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming a pressure slab.

17. A foundation structure comprising at least a pressure plate and a foundation beam erected from the pressure plate, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcing bars, and a portion of each reinforcing bar is embedded at intervals along the longitudinal direction of the precast concrete slab. The precast concrete slab is provided with multiple support legs below it, the lower part of each support leg is fitted into a recess on the upper surface of the lean concrete, and a lower gap is provided between adjacent support legs, with the lower part of each reinforcing bar located in this lower gap. A pair of reinforced precast concrete slabs are arranged with portions of their corresponding reinforcing bars crossing each other, and a post-construction concrete body is formed between them to form a foundation beam, which is a half-precast beam. A foundation structure characterized in that, within the height range of the lower gap, reinforcing bars for the pressure slab are arranged, and a concrete body for the pressure slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming a pressure slab.

18. A foundation structure comprising at least a pressure plate and a foundation beam erected from the pressure plate, Multiple roughly U-shaped or L-shaped reinforcing bars are connected to at least one of the upper or lower main reinforcements. A plurality of separate reinforcing bars, each comprising one or two separate longitudinal bars and corrugated reinforcing bars connected to the separate longitudinal bars and extending in the longitudinal direction to form a corrugated shape, wherein the separate longitudinal bars are embedded at intervals along the longitudinal direction of the precast concrete slab. Each of the aforementioned separate reinforcing bars has its corresponding longitudinal reinforcing bars tied or welded to the corrugated reinforcing bars or longitudinal reinforcing bars of the respective reinforcing bars, and the precast concrete slab is provided with a plurality of support legs below it, the lower part of which is fitted into a recess on the upper surface of the lean concrete, and a lower gap is provided between adjacent support legs, with the lower part of each reinforcing bar located in this lower gap, and a pair of reinforced precast concrete slabs are formed between them, with some of the corresponding reinforcing bars of both slabs crossing each other, thereby forming a foundation beam which is a half-precast beam. A foundation structure characterized in that, within the height range of the lower gap, reinforcing bars for the pressure slab are arranged, and a concrete body for the pressure slab is formed by burying the area below the reinforcing bars and each of the reinforcing bars, thereby forming a pressure slab.

19. Through holes are provided at corresponding positions in the pair of reinforced precast concrete panels. Both ends of a connecting material, which will be embedded in the post-construction concrete body, extend from the through-holes in each of the pair of precast concrete panels. The foundation structure according to claim 17 or 18, characterized in that each of the aforementioned through holes is filled with a filler material.

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