Fabricated cavity concrete backfill device and construction method across top of underground municipal pipe gallery

Abstract

The present application relates to a kind of fabricated cavity concrete replacement device across the top of underground municipal pipe gallery and construction method, and the replacement foundation pit is excavated downwards in the soil layer above pipe gallery, the cavity structure is paved in the replacement foundation pit, the cavity structure includes base, vertical wall I, vertical wall II and superimposed board, the base has cross-shaped mounting slot on it;Multiple groups of base linear array distribution form support foundation, in support foundation, the mounting slot corresponds to each other, form horizontal groove and longitudinal groove;The vertical wall is adapted to be installed in horizontal groove and longitudinal groove, and then form the support system of lattice shape;The superimposed board is assembled on vertical wall, to close the upper portion of support system.The cavity structure of the present application is good in integrity, no wall body overlap between unit cell, wall body is relatively lighter, economic, green, assembly low carbon, can realize fast installation and disassembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricated building construction, in particular to a prefabricated cavity concrete replacement device for crossing the top of an underground municipal pipe gallery and a construction method. BACKGROUND

[0002] With the rapid advancement of urbanization and the demand for resilient city construction, municipal infrastructure construction is increasing, and the existing and new quantities are increasing. In the planning and implementation process of municipal facilities, subsequent new construction is often overlooked, which raises the technical problem of how to cross the existing municipal facilities for new ground building.

[0003] For example, when the new ground building is located between the original buildings, especially when the building crosses the pipe gallery, and when the new building is constructed, most of the original main labor force has been withdrawn, and the reorganization of various types of workers is difficult. Coefficient, at the same time, the inside and outside of the building on both sides of the site have started construction, the site space occupies a large amount of space, and the traditional processing area of some steel, woodworking and other main stages cannot be retained, the construction site is greatly limited, causing construction difficulties.

[0004] In addition, during the construction of the new building, the building bottom elevation needs to be coordinated and unified with the elevation of the surrounding existing municipal road. However, due to the existence of the existing pipe gallery structure, a height difference will be generated between the new building and the upper road surface of the pipe gallery, so the height difference needs to be compensated to ensure that the building bottom elevation meets the design requirements and achieves the standard of building function and use.

[0005] However, the load limit that the pipe gallery structure can bear has been clearly defined in the design, which is usually a constant value. If the traditional concrete replacement and heightening method is used when crossing the pipe gallery, the ground load will be significantly increased, exceeding the design bearing capacity of the pipe gallery, and thus causing deformation or damage to the pipe gallery structure.

[0006] Therefore, there is an urgent need for a construction scheme for crossing the pipe gallery ground modification that is simple, low in construction cost, and fast in construction speed, which can realize the crossing of the new building over the existing municipal facilities under limited construction conditions, and solve the problems of height difference and load limitation. SUMMARY

[0007] In view of this, the purpose of the present application is to provide a prefabricated cavity concrete replacement device for crossing the top of an underground municipal pipe gallery and a construction method, which can effectively solve the ground modification problem of new ground building and the construction difficulty in limited space under the premise of protecting the pipe gallery.

[0008] In order to achieve the above object, the technical scheme adopted by the present application is: a cavity concrete backfill device for assembling on the top of an underground municipal pipe gallery, a backfill foundation is excavated downward in the soil layer above the pipe gallery, a cavity structure is paved in the backfill foundation, the cavity structure comprises a base, a vertical wall I, a vertical wall II and a composite board, the base is provided with a cross-shaped mounting groove; a plurality of groups of bases are linearly arrayed to form a support foundation, the mounting grooves correspond to each other in the support foundation to form horizontal grooves and vertical grooves; the vertical walls are adapted to be installed in the horizontal grooves and the vertical grooves to form a lattice-shaped support system; and the composite board is assembled on the vertical walls to close the upper part of the support system.

[0009] Further, the bases are linearly arrayed in the horizontal and vertical directions to form a support foundation, the top surface of each base is provided with a mounting groove, the mounting groove comprises a horizontal groove and a vertical groove, the horizontal groove and the vertical groove intersect in a cross shape at the center of the base, thereby dividing one base into four identical intervals, and a base plate hook is fixed to the middle part of each base interval.

[0010] Further, a plain concrete cushion layer is arranged below the base, the bases are arrayed on the concrete cushion layer in the horizontal and vertical directions, thereby corresponding to each other between the horizontal grooves and the vertical grooves of adjacent bases, and a longitudinal and transverse intersecting post-poured area I is formed between adjacent bases.

[0011] Further, the vertical wall I and the vertical wall II are both prefabricated reinforced concrete wall components, and have the same height and width, and the length of the vertical wall I is greater than the length of the vertical wall II.

[0012] Further, temporary buttresses are symmetrically arranged at the bottom of the vertical wall I and the vertical wall II, a vertical wall hook is fixed to the middle of the wall above the buttresses, and a hollow area is arranged in the middle of each vertical wall.

[0013] Further, the vertical wall I spans two adjacent bases and is vertically installed in the horizontal grooves of the adjacent bases through the temporary buttresses at the bottom of the vertical wall I and the bent steel bars in the wall; and the vertical wall II spans two adjacent bases and is vertically installed in the vertical grooves of the adjacent bases through the temporary buttresses at the bottom of the vertical wall II and the bent steel bars in the wall.

[0014] Further, a space is left between the sidewall below each vertical wall and the groove wall of the mounting groove on the base to form a cross-shaped post-poured area.

[0015] Further, the end of the horizontally arranged vertical wall I and the vertically arranged vertical wall II forms a cross-shaped area with the center of the mounting groove on the base, the cross-shaped area forms a cross-shaped hidden column through steel binding, and the cross-shaped hidden column is poured with concrete to form a post-poured cross-shaped wall.

[0016] Further, the top of the vertical wall I and the vertical wall II is formed with a convex structure in the middle, and the two sides of the convex structure are used for assembling with the laminated slab.

[0017] The application also provides a construction method of the prefabricated cavity concrete replacement construction across the top of the underground municipal pipe gallery, comprising the following steps:

[0018] Step 1: bottom plate construction; a layer of C20 plain concrete cushion is laid on the top of the pipe gallery, the bases are installed on the concrete cushion in a linear array in the horizontal and vertical directions, the installation grooves are ensured to correspond to each other, the horizontal grooves and the vertical grooves are formed, the rear pouring area I is formed between the adjacent bases, and the concrete is poured in the rear pouring area I formed between the adjacent bases in a horizontal and vertical interlaced manner;

[0019] Step 2: cross-shaped hidden column construction; the position line of the cross-shaped hidden column is accurately laid out on the base, the main reinforcement and the stirrup are bound to form a stable steel reinforcement cage;

[0020] Step 3: vertical wall construction; the vertical wall I is hoisted and assembled in the center of the horizontal groove on the adjacent bottom plate in the horizontal direction, the vertical wall II is hoisted and assembled in the center of the vertical groove on the adjacent bottom plate in the vertical direction, the support is provided by the temporary buttress at the bottom of each vertical wall, and the concrete is poured in the rear pouring area II to vertically fix the vertical wall on the base;

[0021] Step 4: rear pouring cross-shaped wall pouring; the concrete is poured in the cross-shaped hidden column formed in the middle of each bottom plate, the side walls around the cross-shaped hidden column are flush with the vertical walls, the top of the cross-shaped hidden column is flush with the top of each vertical wall, thereby forming a plurality of uniformly arranged grid unit modules to form a lattice-shaped support system;

[0022] Step 5: laminated slab installation and pouring; the laminated slab is hoisted above the grid unit module to realize the precise butt joint and laying of the laminated slab and the vertical wall; then the concrete is poured into the laminated slab cast-in-place layer on the top surface of the laminated slab to complete the closure of the upper part of the support system.

[0023] The beneficial effects of the above technical solution are that the prefabricated cavity concrete replacement construction device across the top of the underground municipal pipe gallery provided by the application can realize the crossing of the newly built building under the limited construction conditions and simultaneously solve the elevation difference and load limitation.

[0024] The device adopts a prefabricated structure and a modular design, including bases, vertical walls and laminated slabs and other prefabricated components, the components can be standardized produced in a factory, then quickly assembled at the construction site, the cavity is arranged in the interior of the prefabricated components to greatly reduce the weight, facilitate the transportation and assembly operation, thereby not only improving the construction efficiency, but also ensuring the quality and stability of the structure.

[0025] The present application forms a support foundation by distributing multiple groups of bases along transverse and longitudinal linear arrays. In the support foundation, mounting grooves correspond to each other to form transverse grooves and longitudinal grooves. The vertical walls are adapted to be mounted in the transverse grooves and longitudinal grooves of adjacent bases to form a solid lattice support system together with the bases. This support system can effectively disperse loads to ensure the structural stability and safety of the entire device.

[0026] The laminated slab is assembled on the top of each vertical wall to close the upper opening of the support system, thereby forming a hollow assembled cavity concrete replacement structure. This structure system not only effectively reduces the structural quality, but also further disperses the load to improve the seismic performance and service life of the structure.

[0027] Through experimental comparison with other schemes, the cavity structure of the present application has good integrity, no wall overlapping between unit cells, relatively light wall self-weight, low transportation cost, economy, green, low-carbon assembly, can realize rapid installation and disassembly, and is convenient for later maintenance and reconstruction. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is a schematic diagram of the assembly structure of the cavity structure and the comprehensive pipe gallery;

[0029] Figure 2 The figure is a comparison diagram of the new building and the top elevation difference of the comprehensive pipe gallery;

[0030] Figure 3 The figure is a schematic diagram of the connection structure of the cavity structure;

[0031] Figure 4 The figure is a schematic diagram of the structure of the base;

[0032] Figure 5 The figure is a schematic diagram of the assembly structure of different types of vertical walls and bases;

[0033] Figure 6 The figure is a schematic diagram of the assembly structure of the post-cast cross-shaped wall in embodiment 1;

[0034] Figure 7 The figure is a schematic diagram of the reinforcement structure in the vertical wall in embodiment 1;

[0035] Figure 8 The figure is a schematic diagram of the construction of the support system in embodiment 1;

[0036] Figure 9 The figure is a schematic diagram of the assembly structure of the vertical wall in embodiment 2;

[0037] Figure 10 The figure is a schematic diagram of the assembly structure of the laminated slab in embodiment 2;

[0038] Figure 11 The figure is Figure 1 The figure is an enlarged structure schematic diagram of position A.

[0039] Figure 12 Assembly structure diagram of the standing wall I and the laminated slab in Example 3;

[0040] Figure 13 Two construction schemes of Comparative Examples 1 and 2; wherein Figure (a) is the construction scheme of Comparative Example 1, and Figure (b) is the construction scheme of Comparative Example 2;

[0041] Figure 14 Material consumption and cost comparison table of three schemes of Example 1 and Comparative Examples 1 and 2.

[0042] The figure marks: 1-cavity structure, 2-original pavement, 3-pile cap, 4-steel column, 5-combined pipe gallery, 6-support pile, 7-newly built ground building, 10-beam, 11-concrete cushion, 12-base, 121-base plate lifting hook, 122-cross groove, 123-longitudinal groove, 13-standing wall I, 14-laminated slab, 15-cavity area, 16-post-cast area I, 17-post-cast area II, 18-laminated slab cast-in-place layer, 19-hollow area, 20-standing wall II, 21-hidden beam longitudinal reinforcement, 22-hidden column, 23-standing wall lifting hook, 24-hidden beam I, 25-longitudinal column reinforcement, 26-hidden beam stirrup, 27-hidden beam II, 28-column longitudinal reinforcement, 29-temporary support pier, 30-post-cast cross-shaped wall, 31-cross-shaped hidden column, 32-large stirrup, 33-small stirrup, 34-tensioning reinforcement, 35-protrusion, 36-positioning cone, 37-positioning groove, 38-truss structure, 39-foamed concrete. DETAILED DESCRIPTION

[0043] The application will be described in further detail below in conjunction with the accompanying drawings and specific embodiments:

[0044] Example 1, which aims to provide a cross-underground municipal pipe gallery top assembly type cavity concrete replacement device, is used to complete the ground modification of the newly built building crossing the existing municipal facilities under the premise of ensuring that the load on the combined pipe gallery is unchanged, and the structure elevation of the combined pipe gallery before the construction of the newly built building, the upper road elevation of the pipe gallery, and the road elevation after the construction of the newly built building are as shown in Figure 2 After the existing newly built building construction is completed, there is often a positive or negative 0 gap with the initial ground elevation, so under the condition that the load on the combined pipe gallery is constant, in order to solve the engineering technical problem of the road elevation difference before and after the construction, the example provides a cross-underground municipal pipe gallery top assembly type cavity concrete replacement device, as shown in Figure 1 which can realize the newly built building crossing the existing municipal facilities under limited construction conditions, and solve the problems of elevation difference and load limitation.

[0045] The cross-underground municipal pipe gallery top assembly type cavity concrete replacement device provided by the embodiment comprises a base, a vertical wall and a laminated slab, the vertical wall comprises prefabricated vertical walls I and II of different lengths, a plurality of groups of bases are distributed in linear arrays along the transverse and longitudinal directions to form a support foundation, in the support foundation, mounting grooves correspond to each other to form transverse grooves and longitudinal grooves, the vertical wall I is adapted to be installed in the transverse grooves of adjacent bases, the vertical wall II is adapted to be installed in the longitudinal grooves of adjacent bases, each base and the surrounding vertical walls form a firm lattice-shaped support system, the laminated slab is assembled on the top of each vertical wall to close the upper opening of the support system, thereby forming an assembly type cavity concrete replacement structure with an internal cavity, and such a structural system can effectively disperse loads and ensure the structural stability and safety of the entire device.

[0046] In a specific structure, as shown in Figure 3 In the embodiment, the base is a prefabricated reinforced concrete base plate component, has good bearing capacity, and is provided with mounting grooves on the top surface, the mounting grooves comprise transverse grooves 122 and longitudinal grooves 123, the transverse grooves and the longitudinal grooves intersect in a cross shape at the center of the base, thereby dividing a base plate into four identical intervals, and a base plate lifting hook 121 is fixed in the middle of each base plate interval, used for lifting connection with lifting equipment and ensuring uniform force during lifting of the base plate.

[0047] As shown in Figure 3 and Figure 4 The base is provided with staggered transverse steel bars and longitudinal steel bars, and in actual site construction, the thickness and reinforcement specifications of the base plate are different according to the actual construction conditions, that is, when the thickness of the base plate is 250 mm, the reinforcement is double-layer double-direction φ12@200, and when the thickness of the base plate is 400 mm, the reinforcement is double-layer double-direction φ14@200, thereby ensuring that the construction is performed according to the corresponding reinforcement requirements under the base plate of different thicknesses.

[0048] A plain concrete cushion layer 11 is arranged below the base plate, in the embodiment, a 100 mm thick C20 plain concrete cushion layer is arranged below the base plate, the bases are arranged in an array along the transverse and longitudinal directions on the concrete cushion layer, the transverse grooves and the longitudinal grooves correspond to each other between adjacent bases, and a longitudinal and transverse staggered post-poured area I 16 is formed between adjacent whole bases, after the vertical walls above the bases are assembled, concrete is poured into the post-poured area I, thereby enabling the vertical walls to be stably erected on the bases.

[0049] Further, by laying a cushion layer under the base, it provides a flat construction base, ensures the installation accuracy of the base plate, and under the action of external load, the plain concrete cushion layer can provide buffering effect, absorb part of the stress, reduce the direct impact on the pipe gallery structure, effectively disperse the load from the upper cavity support system, reduce the uneven settlement of the lower soil layer, improve the stability of the overall structure, and at the same time, the continuity can also play a certain anti-seepage effect, prevent groundwater from eroding the upper structure, and prolong the service life of the structure.

[0050] As shown in Figure 3 and Figure 5 , the vertical wall I and the vertical wall II are both reinforced concrete prefabricated wall panel components, and the height and width of the two are the same, the length of the vertical wall I is greater than the length of the vertical wall II, and the bottom of the vertical wall I 13 and the vertical wall II 20 is symmetrically provided with a temporary support 29 on both sides, and a vertical wall lifting hook 23 is fixed in the middle of the wall body above the support for lifting connection with the lifting equipment, to ensure uniform stress during vertical wall lifting. The middle of the two vertical walls is respectively provided with a hollow area 19, which is a rectangular hole structure in this embodiment, which can effectively reduce the weight of the wall body, while not affecting the bearing capacity of the overall structure.

[0051] Further, as shown in Figure 5 and Figure 7 , during construction, the vertical wall I 13 spans the adjacent two bases 12, and is vertically installed in the horizontal groove 122 of the adjacent base through the temporary support at the bottom of the vertical wall I and the bending steel bars in the wall body, to ensure the stability of the vertical wall before pouring concrete, and the vertical wall II 20 spans the adjacent two bases, and is vertically installed in the longitudinal groove 123 of the adjacent base through the temporary support at the bottom of the vertical wall II and the bending steel bars in the wall body, and the sidewall below each vertical wall and the groove wall of the installation groove on the base are left with a gap, forming a cross-shaped post-pouring area II 17. After the vertical wall construction is completed, concrete is poured into the post-pouring area II 17, and the height of the concrete is flush with the height of the installation groove on the base, so as to vertically fix each vertical wall on the base, ensuring the stable connection of the vertical wall, and forming a lattice-shaped support system.

[0052] As shown in Figure 6 and Figure 8As shown, the ends of each transversely arranged vertical wall I and longitudinally arranged vertical wall II form a cross-shaped area at the center of the mounting slot on the base, and a cross-shaped hidden column 31 is formed by steel binding around the cross-shaped area, and after the construction of the vertical walls around the cross-shaped area is completed, concrete is poured into the cross-shaped hidden column to form a post-poured cross-shaped wall 30. The cross-shaped hidden column serves as an internal support structure and provides an efficient connection node for the entire support system, effectively enhancing the strength and stability at the intersection and ensuring the close combination between the vertical walls; in addition, the post-poured cross-shaped wall helps to optimize the distribution of stress in the structure and reduce stress concentration, thereby effectively improving the shear capacity of the entire support system and the seismic performance and service life of the structure.

[0053] As shown in Figure 3 and Figure 10 , a laminated slab 14 is erected on the top of the vertical wall, and a laminated slab cast-in-place layer 18 is formed above the laminated slab to add a top cover to the top of the lattice-shaped support system formed as described above. Further, the left and right sides of the laminated slab are respectively arranged at the top of the vertical wall II, and the front and back sides are respectively arranged at the top of the vertical wall I. After the laminated slab is overlapped, the top surface of the post-poured cross-shaped wall forms a cross-shaped pouring joint, and by pouring concrete into the laminated slab cast-in-place layer on the top surface of the laminated slab, the pouring joint can be filled, and the upper part of the above support system is closed, forming a solid overall structure.

[0054] The cross-shaped cavity concrete backfill device provided by the embodiment allows flexible adjustment according to actual construction conditions, is suitable for various construction environments and requirements, can ensure that the newly built building can smoothly cross the existing municipal facilities, meets the load requirements, guarantees the structural safety and stability, and provides an effective solution for the newly built building to cross the existing municipal facilities.

[0055] In embodiment 2, the mounting structure of the vertical wall I and the vertical wall II is further described based on embodiment 1.

[0056] As shown in Figure 7 and, a hollow area hole is formed in part of the vertical wall I and the vertical wall II, respectively. The reinforcement in the wall around the hole includes hidden beam longitudinal reinforcement 21, hidden column 22, hidden beam I 24, longitudinal column reinforcement 25, hidden beam stirrup 26, hidden beam II 27, and column longitudinal reinforcement 28, etc. The standard components of the vertical wall I and the vertical wall II are prefabricated by existing steel binding methods. This embodiment further introduces the vertical wall I, as shown in Figure 3 and Figure 11 , a protrusion 35 structure is formed at the top of the vertical wall I, and the two sides of the protrusion are used for overlapping assembly with the laminated slab. After the laminated slab cast-in-place layer is poured with concrete, the formed plane is flush with the top of the protrusion, forming a flat structure.

[0057] The reinforcement in the standing wall in the embodiment includes various steel bar configurations such as hidden beam longitudinal reinforcement, hidden column, hidden beam, and stirrup, enhances the overall bearing capacity and shear strength of the structure, ensures stability under load, and multi-directional reinforcement design can effectively disperse external load and seismic action, improve overall seismic capacity. In addition, the prefabrication of standing wall I and standing wall II allows for quick assembly, making the construction process more efficient, reducing the complexity and risk of on-site construction, shortening the construction period, and improving the safety and efficiency of construction.

[0058] In embodiment 3, on the basis of embodiments 1 and 2, a positioning structure is provided for quick paving during the installation of the superimposed slab, reducing the complexity of manual positioning operations.

[0059] As shown in Figure 12 Each standing wall is a prefabricated standard structure, the positioning structure includes a positioning cone 36 installed on the top of the standing wall, and a positioning groove 37 provided at the bottom of the superimposed slab. The positioning cone is symmetrically provided on both sides of the protruding structure, and 2-4 groups can be respectively provided on the top of standing wall I, and 1-2 groups can be respectively provided on the top of standing wall II, so that when the superimposed slab is hoisted above the standing wall, the positioning groove on the superimposed slab can be matched and fitted on the positioning cone on the standing wall by slightly swinging the position of the superimposed slab, so that the superimposed slab is placed at the preset position.

[0060] In this embodiment, by providing positioning cones on the top of the standing wall and corresponding positioning grooves at the bottom of the superimposed slab, quick and accurate docking can be achieved, greatly reducing the manual positioning time during superimposed slab assembly, allowing it to quickly align and match with the positioning cone, improving construction efficiency and safety.

[0061] In embodiment 4, on the basis of embodiments 1-3, a prefabricated cavity concrete replacement construction method for crossing the top of the underground municipal pipe gallery is provided, which specifically includes the following steps:

[0062] Step 1: After the construction of the surrounding support pile 6, the pile cap 3, the beam 10, and the steel column 4 of the comprehensive pipe gallery is completed, the upper structure of the comprehensive pipe gallery, i.e. the cavity structure 1, is constructed;

[0063] Step 2: Excavate the foundation pit; clean the construction site, including vegetation cleaning and topsoil excavation, then measure and lay out to determine the position of the comprehensive pipe gallery foundation pit excavation line, excavate the foundation pit, and ensure that there is no water in the foundation pit; the foundation of the cavity structure is the backfill soil above the comprehensive pipe gallery, so that the cavity structure is replaced with the original earth constant load;

[0064] Step 3: Base construction; lay a 100mm-thick C20 plain concrete cushion on the bottom of the foundation pit, install the prefabricated reinforced concrete base components (bases) on the concrete cushion in a linear array in the horizontal and vertical directions, ensure that the installation slots correspond to each other, form horizontal and vertical slots, and form post-pouring area I between adjacent bases, and pour concrete in the post-pouring area I formed between adjacent bases to form a stable connection between the bases;

[0065] Step 4: Cross-shaped hidden column construction; according to the requirements of the drawings, accurately lay out the position line of the cross-shaped hidden column on the construction site (on the base), bind the main reinforcement and stirrups to form a stable steel reinforcement cage to prevent displacement during concrete pouring;

[0066] Step 5: Wall installation; use hoisting equipment to hoist the prefabricated reinforced concrete wall components (wall I and wall II) into place, vertically install them in the installation slots of the base through temporary buttresses and bending steel bars in the wall, and pour concrete in the post-pouring area II to vertically fix the walls on the base;

[0067] Step 6: Post-pouring cross-shaped wall pouring; pour concrete into the cross-shaped hidden column formed in the middle of each base to make the four side walls flush with the walls and the top flush with the top of each wall; after the post-pouring area is completely poured, a plurality of uniformly arranged grid unit modules are formed, constituting a lattice-shaped support system;

[0068] Step 7: Installation and pouring of composite slab; hoist the composite slab above the grid unit module, and the operator uses the positioning structure on the composite slab and the wall to realize the precise butt joint of the composite slab and the wall; then pour concrete into the composite slab cast-in-place layer on the top surface of the composite slab to fill the pouring joint and complete the closure of the upper part of the support system.

[0069] Comparative Example 1: As shown in (a) of Figure 13 , the present comparative example provides a steel reinforced concrete truss construction scheme, that is, a steel reinforced concrete truss structure 38 is erected above the comprehensive pipe gallery after the construction of the newly built building is completed, wherein the steel reinforced concrete truss has a span of 40.500m and a center height of 2.5m, to realize the crossing of the newly built building over the existing municipal facilities and to solve the difference in road elevation before and after construction.

[0070] Comparative Example 2: As shown in (b) of Figure 13 , the present comparative example provides a foam concrete backfilling scheme, that is, foam concrete 39 is backfilled above the comprehensive pipe gallery after the construction of the newly built building is completed, to realize the crossing of the newly built building over the existing municipal facilities and to solve the difference in road elevation before and after construction.

[0071] Referring to Figure 14Compared with the actual experiment of example 1, comparative example 1 and comparative example 2, it is found that the truss spanning construction scheme of comparative example 1 has small influence on the built comprehensive pipe gallery, but the construction difficulty of the steel reinforced concrete truss is large, the cycle is long, and the cost is high; the foam concrete scheme of comparative example 2 is convenient for construction, and the cost is lower than that of the truss structure, but the water absorption of the foam concrete leads to the change of the unit weight, the backfilling amount is large, and due to the insufficient strength of the foam concrete, the truss structure is additionally arranged in the actual construction, which increases the construction difficulty. In the hollow cavity structure scheme in the embodiment, the structural integrity is good under the premise of solving the elevation difference and load limitation, the economy, green, assembly low carbon and low cost can be realized, the rapid installation and disassembly can be realized, and the later maintenance and reconstruction are convenient.

[0072] The above-mentioned embodiments of the present application do not constitute a limitation on the protection scope of the present application, and the basic concept of the present application is to use the assembly type hollow cavity structure under the limited construction condition, realize the spanning of the newly built building, fill the road elevation difference, realize the equivalent replacement of the constant load above the comprehensive pipe gallery, and protect the comprehensive pipe gallery structure. Any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A prefabricated cavity concrete replacement device spanning the top of an underground municipal utility tunnel, characterized in that: A replacement pit is excavated downwards from the soil layer above the pipe gallery. A cavity structure is laid inside the replacement pit. The cavity structure includes a base, vertical wall I, vertical wall II, and composite slab. The base has a cross-shaped mounting groove. The ends of the horizontally arranged vertical wall I and the longitudinally arranged vertical wall II form a cross-shaped area with the center of the mounting groove on the base. This area is reinforced with steel bars to form a cross-shaped hidden column. Concrete is poured into the cross-shaped hidden column to form a post-cast cross-shaped wall. The base is arranged in a linear array along the horizontal and vertical directions to form a supporting foundation. The top surface of the base is provided with mounting grooves, which include horizontal grooves and vertical grooves. The horizontal grooves and vertical grooves intersect in a cross shape at the center of the base, thereby dividing a base into four identical sections. A bottom plate hook is fixed in the middle of each base section. A plain concrete pad is provided under the base. The bases are arranged in a horizontal and vertical array on the concrete pad, so that the horizontal grooves and vertical grooves of adjacent bases correspond to each other, and a crisscrossing post-cast area I is formed between adjacent base sections. Temporary supports are symmetrically provided on both sides of the bottom of the vertical wall I and vertical wall II. A wall hanging hook is fixed in the center of the wall above the support. Each vertical wall has a hollow area in the middle. Vertical wall I spans two adjacent bases and is vertically installed in the horizontal groove of the adjacent base through the temporary supports at the bottom of vertical wall I and the bent steel bars in the wall. Vertical wall II spans two adjacent bases and is vertically installed in the longitudinal groove of the adjacent base through the temporary supports at the bottom of vertical wall II and the bent steel bars in the wall. Multiple sets of bases are linearly arrayed to form a support foundation. In the support foundation, the mounting slots correspond to each other to form horizontal and vertical slots. The vertical walls are fitted and installed in the horizontal and vertical slots, thus forming a grid-like support system. The composite plate is assembled on the vertical wall to enclose the upper part of the support system.

2. The prefabricated hollow concrete replacement device for crossing the top of an underground municipal utility tunnel as described in claim 1, characterized in that: Both wall I and wall II are precast reinforced concrete wall panel components, with the same height and width, and wall I is longer than wall II.

3. The prefabricated hollow concrete replacement device for the top of an underground municipal utility tunnel as described in claim 1, characterized in that: The top of the vertical wall I and vertical wall II forms a raised structure at the middle, and the two sides of the raised structure are used for assembly with the composite plate.

4. A method for constructing prefabricated hollow concrete replacement for the top of an underground municipal utility tunnel, using the prefabricated hollow concrete replacement device for the top of an underground municipal utility tunnel as described in any one of claims 1-3, characterized in that: Includes the following steps: Step 1: Base plate construction; First, lay a layer of C20 plain concrete on the soil covering the top of the pipe gallery. Then, install the bases in a horizontal and vertical linear array on the concrete base, ensuring that the installation grooves correspond to each other to form horizontal and vertical grooves, so that a post-pouring zone I is formed between adjacent bases. Concrete is then poured in the crisscrossing post-pouring zone I formed between adjacent bases. Step 2: Construction of the cross-shaped concealed column; accurately mark the position line of the cross-shaped concealed column on the base, and tie the main reinforcement and stirrups to form a stable steel reinforcement skeleton; Step 3: Erect wall construction; Erect wall I is hoisted and assembled horizontally to the center of the horizontal groove on the adjacent base plate, and erect wall II is hoisted and assembled longitudinally to the center of the longitudinal groove on the adjacent base plate. Temporary supports are used at the bottom of each wall for support, and concrete is poured in post-cast area II to vertically fix the wall to the base. Step 4: Constructing the cross-shaped wall; Concrete is poured into the cross-shaped hidden columns formed in the middle of each base plate, so that its four sides are flush with the vertical walls and its top is flush with the top of each vertical wall, thus forming multiple evenly arranged grid unit modules, which constitute a grid-like support system. Step 5: Installation and pouring of composite slabs; hoist the composite slabs above the grid unit modules to achieve precise connection and laying of the composite slabs and the vertical walls; then pour concrete onto the top surface of the composite slabs to complete the closure of the upper part of the support system.

Images