Construction method of cast-in-place beam lattice

Abstract

The invention relates to the technical field of wharf construction, in particular to a construction method of a cast-in-place beam lattice, the beam lattice is divided into two pouring areas according to the pouring volume of the beam lattice, two discharging pipes are adopted to conduct pouring operation on the two pouring areas respectively, and the construction method comprises the following steps that a first slope layer is firstly formed at the starting end of a longitudinal beam through the discharging pipes; the discharging pipe is moved from the slope bottom to the slope top of the first slope layer to be poured to form a second slope layer; the discharging pipe is moved from the slope bottom to the slope top of the second slope layer to be poured to form the next second slope layer; the steps are repeated until pouring of the beam lattices is completed; wherein the two pouring areas are synchronously propelled. Compared with a horizontal layered pouring mode, the slope layered pouring mode has the advantages that the time for waiting for pouring of the next layer of each layered layer can be greatly shortened, so that pouring cold joints formed in the pouring process of the beam lattice structure are reduced, and the stress performance and durability of the beam lattice structure are improved.

Description

Technical Field

[0001] The invention relates to the technical field of dock construction, and in particular to a construction method of a cast-in-place beam grillage. Background Art

[0002] During the construction of the wharf, after the pile foundation construction is completed and formed, formwork is usually carried out on the top of the pile foundation to construct a criss-cross beam grid formwork system. Subsequently, the beam grid reinforcement binding work is carried out according to the construction process, and the concrete pouring operation is implemented. In the wharf beam grid structure, the overall length is often tens of meters. From the cross-sectional dimensions of a single beam or longitudinal beam, the width can reach 1m to 2m, and the height is in the range of 2m to 4m. Given such a large cross-sectional size, the concrete pouring volume of the entire beam grid is considerable. At the same time, considering the particularity of the wharf's geographical location, it is close to the water and the construction site is limited. Generally, only two sky pumps can be set up on the shore at the same time for concrete pouring operations.

[0003] If the traditional construction method of horizontal layered pouring of the integral beam grid is adopted, the time required to complete each layer of pouring is likely to exceed the initial setting time of the concrete due to the huge pouring volume. In this case, pouring cold joints are easily formed between different pouring layers. The existence of these cold joints will have an adverse effect on the mechanical performance and durability of the wharf beam grid structure. Therefore, it is necessary to study a new construction scheme suitable for beam grid concrete pouring. Summary of the invention

[0004] The purpose of the present invention is to overcome the problem existing in the prior art that when the construction site is limited, only two pump trucks can be arranged at the same time for pouring concrete on the beam grid of the dock. However, due to the large pouring volume, the beam grid is prone to cold joints during the pouring process, and a construction method for a cast-in-place beam grid is provided.

[0005] The present invention provides a construction method for a cast-in-place beam grid, wherein the beam grid comprises a plurality of transverse beams and a plurality of longitudinal beams, and the beam grid is divided into two casting areas distributed in a transverse direction according to the casting volume of the beam grid, and the casting volume of the two casting areas differs by at most the volume of one longitudinal beam; Two discharge pipes are used to perform pouring operations on the two pouring areas respectively. During pouring, pouring is performed longitudinally from the same end of the two pouring areas to the other end. The pouring process includes the following steps: S1: firstly forming a first slope layer at the starting end of the longitudinal beam through the discharge pipe; S2: moving the discharge pipe along the bottom of the first slope layer to the top of the slope to form a second slope layer; S3: moving the discharge pipe along the bottom of the second slope layer toward the top of the slope to form the next second slope layer; S4: Repeat step S3 until the casting of the beam grid is completed; wherein steps S1-S4 of the two casting areas are carried out simultaneously.

[0006] The cross beam and the longitudinal beam are arranged perpendicular to each other, the length direction along the longitudinal beam is the longitudinal direction, and the length direction along the cross beam is the transverse direction. The longitudinal directions of the two casting areas distributed along the transverse direction are also arranged along the length direction of the longitudinal beam.

[0007] The present invention provides a construction method for a cast-in-place beam grid, wherein the beam grid is divided into two casting areas to clarify the casting areas of the two discharge pipes. The casting volume of the two casting areas differs by at most the volume of one longitudinal beam, thereby reducing the difference in casting volume of the two casting areas and ensuring that the two casting areas can be cast synchronously along the longitudinal direction of the beam grid. During the entire casting process, since the concrete has fluidity, the concrete in the longitudinal beam can flow into the cross beam.

[0008] The discharge pipe first forms a first slope layer at the starting end of the longitudinal beam, and the first slope layer forms an initial casting layer with a slope surface. Then, the discharge pipe is moved along the bottom of the first slope layer to the top of the slope to cast a second slope layer, and then the discharge pipe is moved along the bottom of the second slope layer to the top of the slope to cast the next second slope layer, and this is repeated until the casting of the beam grid is completed. The slope surface length of the first slope layer and the slope surface length of the second slope layer are both smaller than the length of the longitudinal beam. Therefore, the present invention can significantly shorten the time for each layer surface to wait for the next layer to be cast, compared with the horizontal layered casting method, through this slope layered casting method, thereby reducing the casting cold joints formed in the beam grid structure during the casting process, thereby improving the stress performance and durability of the beam grid structure.

[0009] When pouring each layer, the discharge pipe moves from the bottom of the slope to the top of the slope of each pouring layer. The purpose of this solution is to use the concrete below the slope to provide support for the subsequent concrete poured above the slope in the same pouring layer, thereby reducing the flow of concrete and further reducing the occurrence of concrete bleeding.

[0010] When there is only one longitudinal beam in the casting area, the discharge pipe only needs to perform casting along the length direction of the longitudinal beam in the corresponding area. When there are multiple longitudinal beams in the casting area, the discharge pipe needs to first cast a predetermined length on one of the longitudinal beams, then move to the next longitudinal beam in the same casting area, and cast the predetermined length as well, and continue this process until all the longitudinal beams in the corresponding casting area are cast.

[0011] It should be noted that the boundary between the two casting areas should be divided on the cross beam and cannot be divided on the longitudinal beam.

[0012] Preferably, when the discharge pipe moves to the node position where the longitudinal beam and the transverse beam intersect, the discharge pipe is moved to the transverse beam adjacent to the node to cast the missing material area of ​​the transverse beam. This solution can ensure that when the two casting areas are cast in the longitudinal direction of the beam grid simultaneously, the concrete casting of the transverse beam can be taken into account, thereby avoiding the situation where the transverse beam is missing material or missed casting.

[0013] Preferably, the height of the first slope layer is 0.4m-0.5m. The height specifically refers to the size or size range of the first slope layer in the vertical direction (usually perpendicular to the ground), that is, the vertical distance from the bottom to the top of the first slope layer.

[0014] Preferably, the angle between the slope surface of the first slope layer and the horizontal plane is 10° to 30°.

[0015] Preferably, the thickness of the second slope layer is 0.4m-0.6m. The casting thickness refers to the height of the second slope layer in a direction perpendicular to the slope surface of the first slope layer.

[0016] Preferably, when pouring the first slope layer and the second slope layer, a vibrating rod is used to follow the discharge pipe to vibrate each layer of poured concrete. The purpose of this solution is to vibrate the poured concrete in layers in a timely manner, discharge bubbles in the concrete, improve the density of the concrete, and reduce concrete pouring quality problems such as honeycombs and rough surfaces. If the vibration operation is performed after the concrete is poured to the finished surface, it will be difficult for the concrete at a deeper position to be fully and effectively vibrated.

[0017] Preferably, the ratio of the discharge rates of the two discharge pipes is proportional to the ratio of the volumes of the two casting areas corresponding to the two discharge pipes. The purpose of this solution is to enable the two casting areas to be cast synchronously along the longitudinal direction of the beam grid, so as to ensure that the two casting areas can be cast at the same time, thereby reducing the possibility of casting cold joints at the junction of the two casting areas.

[0018] Preferably, before the pouring operation begins, a steel mesh is set at the position where the two pouring areas meet, and the mesh size of the steel mesh is 1mm-3mm. The steel mesh is used to limit the flow of concrete between the two pouring areas, so that the concrete pouring volume required for the two pouring areas is clear, and further ensures that the two pouring areas can be poured synchronously along the longitudinal direction of the beam grid.

[0019] Preferably, before the pouring operation begins, a retarder is added to the concrete to be pumped. The retarder prolongs the initial setting time of the concrete, providing a more ample time window for the construction operation, thereby further effectively reducing the generation of cold joints during pouring.

[0020] Preferably, when the longitudinal beam includes a first longitudinal beam, a second longitudinal beam and a track longitudinal beam arranged side by side in sequence, and the cross-sectional areas of the first longitudinal beam and the second longitudinal beam are both smaller than the track longitudinal beam, the first longitudinal beam and the second longitudinal beam are divided into one casting area, and the track longitudinal beam is divided into another casting area.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a construction method for a cast-in-place beam grillage. Compared with a horizontal layered casting method, the sloped layered casting method can greatly shorten the time for each layer surface to wait for the next layer to be cast, thereby reducing the casting cold joints formed in the beam grillage structure during the casting process, thereby improving the stress performance and durability of the beam grillage structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a plan view of the beam grillage of the present invention.

[0023] Figure 2 for Figure 1 Schematic diagram of cross-section casting along the CC cutting line.

[0024] Markings in the figure: 1- beam, 2- First longitudinal beam, 3- Second longitudinal beam, 4- Track longitudinal beam, 5-dividing line, 6- The first pouring area, 7- The second pouring area, 8- The first discharge pipe, 9- Second discharge pipe, 10- First slope layer, 11- Second slope layer. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0026] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or are the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0027] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0028] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0029] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0030] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0031] Example 1 A construction method for a cast-in-place beam grid, wherein the beam grid comprises a plurality of transverse beams 1 and a plurality of longitudinal beams, wherein the beam grid is divided into two casting areas distributed in a transverse direction according to the casting volume of the beam grid, and the casting volume of the two casting areas differs by at most the volume of one longitudinal beam; Two discharge pipes are used to perform pouring operations on the two pouring areas respectively. During pouring, pouring is performed longitudinally from the same end of the two pouring areas to the other end. The pouring process includes the following steps: S1: Firstly, a first slope layer 10 is formed at the starting end of the longitudinal beam through the discharge pipe.

[0032] S2: The discharge pipe is moved along the bottom of the first slope layer 10 to the top of the slope to form a second slope layer 11 by casting.

[0033] S3: The discharge pipe is moved along the bottom of the second slope layer 11 toward the top of the slope to form the next second slope layer 11 by casting.

[0034] S4: Repeat step S3 until the casting of the beam grid is completed; wherein steps S1-S4 of the two casting areas are carried out simultaneously.

[0035] Specifically, Figure 1 As shown, the beam grid includes a crossbeam 1 and a plurality of longitudinal beams. The beam grid is divided into a first pouring area 6 and a second pouring area 7 along the transverse direction of the beam grid. The pouring volume of the first pouring area 6 and the second pouring area 7 differs by at most the volume of one longitudinal beam. The transverse direction of the beam grid is consistent with the length direction of the crossbeam 1, and the longitudinal direction of the beam grid is consistent with the length direction of the longitudinal beam. The construction method comprises the following steps: The first discharge pipe 8 and the second discharge pipe 9 are cast from the same end of the beam grid to the other end along the longitudinal direction of the beam grid; the first discharge pipe 8 and the second discharge pipe 9 respectively cast the first casting area 6 and the second casting area 7. The first discharge pipe 8 and the second discharge pipe 9 are the discharge pipes on the arm systems of the two sky pumps.

[0036] The first discharge pipe 8 first casts the starting end of the longitudinal beam in the first casting area 6, keeps the first discharge pipe 8 at the initial position for a predetermined time, that is, keeps the first discharge pipe 8 at the starting end, and uses the fluidity of concrete to form the first slope layer 10 in the first casting area 6, and then casts in layers along the slope direction of the first slope layer 10 to form the second slope layer 11 in the first casting area 6. When each layer is cast, the first discharge pipe 8 moves from the bottom of each casting layer to the top of the slope. Specifically, the left end of the longitudinal beam can be set as the starting end of the casting operation, and the right end of the longitudinal beam can be set as the ending end of the casting operation.

[0037] The second discharge pipe 9 first casts the starting end of the longitudinal beam in the second casting area 7, keeps the second discharge pipe 9 at the initial position for a predetermined time, that is, keeps the second discharge pipe 9 at the starting end, and uses the fluidity of concrete to form the first slope layer 10 in the second casting area 7, and then casts in layers along the slope direction of the first slope layer 10 to form the second slope layer 11 in the second casting area 7. When each layer is cast, the second discharge pipe 9 moves from the bottom of each casting layer to the top of the slope. Figure 2 As shown, the figure presents a layered pouring method.

[0038] The pouring of the beam grid is completed until the first discharge pipe 8 is poured to the end of the longitudinal beam in the first pouring area 6 and the second discharge pipe 9 is poured to the end of the longitudinal beam in the second pouring area 7.

[0039] During the pouring of the longitudinal beam, since the cross beam 1 and the longitudinal beam are connected and the concrete has a certain fluidity, the cross beam 1 will also be gradually filled with concrete.

[0040] In an optional embodiment, when the discharge pipe moves to the node position where the longitudinal beam and the cross beam 1 intersect, the discharge pipe can be moved to the cross beam 1 adjacent to the node to cast the missing material area of ​​the cross beam 1. This solution can not only supplement the missing material area in the cross beam 1, but also improve the speed of casting the entire cross beam 1.

[0041] In an optional implementation, the height of the first slope layer 10 may be 0.4m-0.5m, and the specific height may be 0.4m, 0.45m, or 0.5m.

[0042] In an optional embodiment, the angle between the slope surface of the first slope layer 10 and the horizontal plane can be 10° to 30°, and the specific angle can be 10°, 15°, 20°, 25°, or 30°.

[0043] In an optional embodiment, the thickness of the second slope layer 11 can be 0.4m-0.6m, and the specific thickness can be 0.4m, 0.45m, 0.5m, 0.55m, 0.6m. Specifically, the discharge pipe can also swing along the width direction of the longitudinal beam during pouring. When pouring along the slope of the first slope layer 10 and the slope of the second slope layer 11, the discharge pipe can move at a uniform speed, or dynamically adjust the moving speed according to the thickness of the current pouring point to ensure that the pouring thickness of each layer meets the predetermined requirements.

[0044] In an optional embodiment, when pouring the first slope layer 10 and the second slope layer 11, a vibrating rod is used to follow the discharge pipe to vibrate each layer of poured concrete. Specifically, the vibrating rod can penetrate 10cm-15cm into the lower layer of concrete, and the vibration time at each location can be 15 seconds-25 seconds.

[0045] In an optional embodiment, the ratio of the discharge rates of the two discharge pipes may be proportional to the ratio of the volumes of the two casting areas respectively corresponding to the two discharge pipes.

[0046] In an optional embodiment, before the pouring operation begins, a steel mesh can be set at the position where the two pouring areas meet, and the mesh size of the steel mesh is 1mm-3mm, and the mesh size can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm. Specifically, the steel mesh can be tied to the steel bars of the beam 1 by iron wire. The mesh surface formed by the steel mesh can be exactly parallel to the plane where the cross section of the beam 1 is located.

[0047] In an optional embodiment, before the pouring operation begins, a retarder can be added to the concrete to be pumped. Specifically, the retarder addition operation is completed at a concrete pumping station. The dosage of the retarder can be 0.2%-0.6% of the cement dosage.

[0048] In an optional embodiment, when the longitudinal beam includes a first longitudinal beam 2, a second longitudinal beam 3 and a rail longitudinal beam 4 arranged side by side in sequence, and the cross-sectional areas of the first longitudinal beam 2 and the second longitudinal beam 3 are both smaller than the rail longitudinal beam 4, the first longitudinal beam 2 and the second longitudinal beam 3 can be divided into one casting area, and the rail longitudinal beam 4 can be divided into another casting area.

[0049] Specifically, the first longitudinal beam 2 and the second longitudinal beam 3 are divided into the first casting area 6, and the track longitudinal beam 4 is divided into the second casting area 7. The beam grid can be divided into the first casting area 6 and the second casting area 7 using a dividing line 5 parallel to the track longitudinal beam 4, and the dividing line 5 is located between the second longitudinal beam 3 and the track longitudinal beam 4.

[0050] Specifically, when the volume ratio of the first pouring area 6 to the second pouring area 7 is 6:5, the ratio of the discharge rate of the first discharge pipe 8 to the second discharge pipe 9 is also 6:5.

[0051] When pouring in the first pouring area 6 using the first discharge pipe 8, first pour a predetermined length along the first longitudinal beam 2, then move the first discharge pipe 8 to the starting end of the second longitudinal beam 3, pour a predetermined length in the same manner as the pouring of the first longitudinal beam 2, and then move the first discharge pipe 8 to the first longitudinal beam 2, and alternately complete the pouring of the first pouring area 6. The predetermined length can be 0.8 times to 1.5 times the single span of the first longitudinal beam 2, and specifically can be 0.8 times, 1 times, 1.2 times, 1.5 times.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method for cast-in-place beam grillage, characterized in that: The beam grid comprises a plurality of transverse beams (1) and a plurality of longitudinal beams, and the beam grid is divided into two casting areas distributed in the transverse direction according to the casting volume of the beam grid, and the casting volume of the two casting areas differs by at most the volume of one longitudinal beam; Two discharge pipes are used to perform pouring operations on the two pouring areas respectively. During pouring, pouring is performed longitudinally from the same end of the two pouring areas to the other end. The pouring process includes the following steps: S1: firstly forming a first slope layer (10) at the starting end of the longitudinal beam through the discharge pipe; S2: moving the discharge pipe along the bottom of the first slope layer (10) toward the top of the slope to form a second slope layer (11); S3: moving the discharge pipe along the bottom of the second slope layer (11) toward the top of the slope to form the next second slope layer (11); S4: Repeat step S3 until the casting of the beam grid is completed; wherein steps S1-S4 of the two casting areas are carried out simultaneously.

2. The construction method of a cast-in-place beam grillage according to claim 1, characterized in that: When the discharge pipe moves to the node position where the longitudinal beam and the cross beam (1) intersect, the discharge pipe is moved to the cross beam (1) adjacent to the node, and the material shortage area of ​​the cross beam (1) is cast.

3. The construction method of a cast-in-place beam grillage according to claim 1, characterized in that: The height of the first slope layer (10) is 0.4m-0.5m.

4. The construction method of a cast-in-place beam grillage according to claim 3, characterized in that: The angle between the slope surface of the first slope layer (10) and the horizontal plane is 10° to 30°.

5. The construction method of a cast-in-place beam grillage according to claim 1, characterized in that: The thickness of the second slope layer (11) is 0.4m-0.6m.

6. The construction method of a cast-in-place beam grillage according to claim 1, characterized in that: When pouring the first slope layer (10) and the second slope layer (11), a vibrating rod is used to follow the discharge pipe to vibrate each layer of poured concrete.

7. A construction method for a cast-in-place beam grillage according to any one of claims 1 to 6, characterized in that: The ratio of the discharge rates of the two discharge pipes is proportional to the ratio of the volumes of the two casting areas respectively corresponding to the two discharge pipes.

8. The construction method of a cast-in-place beam grillage according to claim 7, characterized in that: Before the pouring operation begins, a wire mesh is set at the location where the two pouring areas meet, and the mesh size of the wire mesh is 1mm-3mm.

9. The construction method of a cast-in-place beam grillage according to claim 7, characterized in that: Before pouring operations begin, a retarder is added to the concrete to be pumped.

10. The construction method of a cast-in-place beam grillage according to claim 7, characterized in that: When the longitudinal beam comprises a first longitudinal beam (2), a second longitudinal beam (3) and a track longitudinal beam (4) arranged in sequence side by side, and the cross-sectional areas of the first longitudinal beam (2) and the second longitudinal beam (3) are both smaller than the track longitudinal beam (4), the first longitudinal beam (2) and the second longitudinal beam (3) are divided into one casting area, and the track longitudinal beam (4) is divided into another casting area.

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