A method for constructing a lattice column through-hole penetrating a box culvert top plate

Abstract

The present invention relates to a construction method for a lattice column through hole that penetrates a box culvert top plate. A rubber sleeve with a rectangular cross section is sleeved on the lattice column. A row of steel bar insertion holes are respectively arranged on the four side walls of the rubber sleeve according to the number and spacing of steel bars on each side of the lattice column through hole. A steel bar insertion and extraction channel is arranged between each steel bar insertion hole and the bottom edge of the sleeve. When tying the steel bars of the box culvert top plate, the steel bar ends at the lattice column through holes are respectively inserted into each steel bar through hole, and the rubber sleeve is used as a lattice column through hole casting template. After the box culvert top plate concrete is poured, the rubber sleeve is pulled out upward to expose the end steel bars, and then the lattice column is cut off, the steel bars are connected, and concrete for repairing the lattice column through holes is poured. The template of the present invention has a fast installation and disassembly speed, saves the bending and straightening process of the end steel bars at the lattice column through holes, and can improve the construction efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of underground drainage box culvert construction, and in particular relates to a method for constructing lattice column through holes on a box culvert top plate. Background Art

[0002] When constructing an underground drainage box culvert, it is necessary to excavate a foundation pit and set up cross braces between the steel sheet piles on both sides of the foundation pit. Since the cross section of the foundation pit is large, the span of the cross brace is also relatively large. In order to ensure the stability of the cross brace, lattice columns are usually set below the middle of the cross brace to support the cross brace. Figure 1 As shown, the lower end of the lattice column 1 is supported on the box culvert bottom plate 2, and the upper end passes through the box culvert top plate 3 and is supported on the bottom surface of the cross brace 4.

[0003] In box culvert construction, the bottom plate is usually poured first, and then the side plates and top plates are poured in sequence. Generally, the lattice columns are set after the bottom plate is poured. Therefore, when pouring the top plate, it is necessary to leave lattice column through holes 5 at the positions where the lattice columns pass through the top plate. After the concrete pouring of the box culvert top plate is completed, the lattice columns are removed and the lattice column through holes are repaired with concrete.

[0004] In order to form the lattice column through hole on the box culvert top plate, it is necessary to set the side formwork 6 around the lattice column when pouring the box culvert top plate. Figure 1 As shown, during current construction, the side formwork 6 is generally made of bamboo plywood. To ensure the stability of the side formwork, it is necessary to set a support rod 7 between the lattice column 1 and the side formwork 6, or to stick the formwork to the steel pipe pile. The support and later demoulding of the formwork take a long time.

[0005] In addition, when tying the top plate steel bars 8, since the top plate steel bars cannot pass through the lattice column, it is necessary to reserve steel bar joints at the through holes of the lattice column, and then connect the steel bar joints when repairing the through holes later. Figure 1 The template installation method shown requires that the top plate steel bars 8 be bent 90 degrees at the lattice column through-holes, and the steel bars 8 need to be straightened one by one after the template is removed, which is a cumbersome process and has low construction efficiency. Summary of the invention

[0006] The object of the present invention is to solve the above-mentioned problems and provide a method for constructing a lattice column through hole that penetrates a box culvert top plate, so as to improve the construction efficiency of the box culvert top plate.

[0007] The technical solution of the present invention is as follows:

[0008] A method for constructing a lattice column through hole penetrating a box culvert top plate, characterized in that it comprises the following steps:

[0009] (1) When installing the lattice column, a rubber sleeve is sleeved on the lattice column, and the rubber sleeve is used as a casting template for the lattice column through hole on the box culvert top plate; the cross-section of the rubber sleeve is rectangular, the axial height of the rubber sleeve is greater than the thickness of the box culvert top plate, the cross-sectional size of the inner cavity of the rubber sleeve is consistent with the cross-sectional size of the lattice column, and a row of steel bar insertion holes are respectively arranged on the four side walls of the rubber sleeve according to the number and spacing of steel bars on each side of the lattice column through hole, the distance between each row of steel bar insertion holes and the bottom edge of the rubber sleeve is not less than the distance between the steel bars of the box culvert top plate and the bottom surface of the box culvert top plate, and a steel bar insertion and extraction channel is arranged between each steel bar insertion hole and the bottom edge of the rubber sleeve along the axial direction of the rubber sleeve;

[0010] (2) When tying the steel bars of the top plate of the box culvert, insert the ends of the steel bars at the through holes of the lattice columns into the through holes of the steel bars along the steel bar insertion and extraction channels on the rubber sleeves, so that the rubber sleeves are hung on the steel bars of the top plate;

[0011] (3) Install the bottom formwork and outer formwork of the box culvert top slab and pour the concrete of the box culvert top slab;

[0012] (4) After the concrete of the box culvert top plate reaches the demolding strength, the rubber sleeve is pulled out upward to expose the end steel bars. Then the lattice column is cut off, the steel bars at the lattice column through holes are connected, and concrete is poured to repair the lattice column through holes.

[0013] The present invention can directly hang the template on the top plate steel bars at the through holes of the lattice columns, and the steel bar ends are inserted into the template without bending. The template can be installed quickly, and the end steel bars can be exposed by pulling the template upwards when removing the template, thus saving the end steel bar straightening process and improving construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the installation structure of the existing lattice column through-hole template;

[0015] Figure 2 It is a schematic diagram of the state of installing a rubber sleeve on a lattice column;

[0016] Figure 3 It is a schematic diagram of the three-dimensional structure of the rubber sleeve;

[0017] Figure 4 It is a schematic diagram of the cross section of the rubber sleeve at the steel bar channel;

[0018] Figure 5 This is a schematic diagram of the rubber sleeve hanging on the end steel bar;

[0019] Figure 6 This is a schematic diagram of the state after the concrete pouring of the box culvert top slab is completed;

[0020] Figure 7 It is a schematic diagram of the planar structure at the through hole of the lattice column after the rubber sleeve is pulled out. DETAILED DESCRIPTION

[0021] The construction method of the present invention is as follows:

[0022] like Figure 2 , Figure 3 , Figure 4 As shown, after the construction of the box culvert bottom plate is completed, when the lattice column 1 is installed, a rubber sleeve 9 is sleeved on the lattice column, and the rubber sleeve serves as a casting template for the lattice column through hole on the box culvert top plate;

[0023] The cross section of the rubber sleeve 9 is rectangular, the axial height of the rubber sleeve is greater than the thickness of the box culvert top plate, the cross-sectional size of the inner cavity of the rubber sleeve is consistent with the cross-sectional size of the lattice column, and a row of steel bar insertion holes 10 are respectively arranged on the four side walls of the rubber sleeve according to the number and spacing of steel bars on each side of the through hole of the lattice column, and the distance between each row of steel bar insertion holes 10 and the bottom edge of the rubber sleeve is not less than the distance between the steel bars of the box culvert top plate and the bottom surface of the box culvert top plate, and a steel bar insertion and extraction channel 11 is arranged between each steel bar insertion hole and the bottom edge of the rubber sleeve along the axial direction of the rubber sleeve;

[0024] When the present invention is implemented, a rectangular solid rubber block can be used, and a hole consistent with the cross-sectional size of the lattice column can be cut in the middle to form a rubber sleeve. The rubber sleeve should retain a wall thickness of not less than 2 cm so that the end of the steel bar can be inserted into the side wall of the rubber sleeve for a certain length, which is convenient for the later connection between the ends of the steel bars. A row of steel bar through holes are drilled on the four side walls of the rubber sleeve according to the number and spacing of the top plate steel bars at the through holes of the lattice column, and an opening is cut between each steel bar through hole and the bottom edge of the sleeve as a steel bar channel. The steel bar channel can be in a closed state due to the elasticity of the rubber, which can prevent leakage of concrete during pouring.

[0025] like Figure 5 As shown, when tying the steel bars 8 of the top plate of the box culvert, the steel bar ends at the through holes of the lattice columns are slid upward along the steel bar insertion and extraction channels 11 on the template, and inserted into the steel bar through holes 10 on the template, so that the rubber sleeve is hung on the top plate steel bars 8;

[0026] like Figure 6 As shown, install the bottom formwork and outer formwork of the box culvert top slab, and pour the top slab concrete;

[0027] like Figure 7 As shown, after the top slab concrete reaches the demolding strength, the rubber sleeve is pulled out upward to expose the straight end steel bar 8, and then the lattice column is cut off, the steel bars at the lattice column through holes are connected, and concrete for repairing the lattice column through holes is poured to complete the box culvert construction.

Claims

1. A method for constructing a through hole of a lattice column penetrating a box culvert top plate, It is characterized in that The following steps are involved: (1) When installing the lattice column, a rubber sleeve is sleeved on the lattice column, and the rubber sleeve is used as a casting template for the lattice column through hole on the box culvert top plate; the cross-section of the rubber sleeve is rectangular, the axial height of the rubber sleeve is greater than the thickness of the box culvert top plate, the cross-sectional size of the inner cavity of the rubber sleeve is consistent with the cross-sectional size of the lattice column, and a row of steel bar insertion holes are respectively arranged on the four side walls of the rubber sleeve according to the number and spacing of steel bars on each side of the lattice column through hole, the distance between each row of steel bar insertion holes and the bottom edge of the rubber sleeve is not less than the distance between the steel bars of the box culvert top plate and the bottom surface of the box culvert top plate, and a steel bar insertion and extraction channel is arranged between each steel bar insertion hole and the bottom edge of the rubber sleeve along the axial direction of the rubber sleeve; (2) When tying the steel bars of the top plate of the box culvert, insert the ends of the steel bars at the through holes of the lattice columns into the through holes of the steel bars along the steel bar insertion and extraction channels on the rubber sleeves, so that the rubber sleeves are hung on the steel bars of the top plate; (3) Install the bottom formwork and outer formwork of the box culvert top slab and pour the concrete of the box culvert top slab; (4) After the concrete of the box culvert top plate reaches the demolding strength, the rubber sleeve is pulled out upward to expose the end steel bars. Then the lattice column is cut off, the steel bars at the lattice column through holes are connected, and concrete is poured to repair the lattice column through holes.

Images