CN104018518B - The method of prefabricated diaphragm wall and construction outer wall of basement and floor - Google Patents

Abstract

The invention discloses a prefabricated underground continuous wall and a method for constructing basement exterior walls and floor slabs. The continuous wall comprises a wall unit (1) and a pile foundation (2), and a plurality of wall units (1) are stacked vertically to form a wall row, the prestressed steel bar (7) tensions all the wall monomers (1) and pile foundations (2) of the row of walls and fills the prestressed hole (3) with cement slurry; each wall monomer (1) A row of multiple reserved holes and pre-embedded steel plates are provided on the inner surface of the wall, and connecting steel bars are provided in each reserved hole; the key to this method is to tension the prestressed steel bars (7), so that all the wall monomers ( 1) and the pile foundation (2) are tensioned, and the horizontal steel bars of the floor reinforcement cage are extended into the reserved holes to connect with the connecting steel bars. The diaphragm wall and the construction method can speed up the construction speed, shorten the construction period, have good lateral shear resistance and longitudinal compression resistance, and the concrete of the diaphragm wall does not need to be knocked off when the floor is constructed.

Description

Prefabricated underground diaphragm wall and method for constructing basement exterior walls and slabs

technical field

The invention relates to underground structure construction technology in the field of civil engineering, in particular to a prefabricated underground diaphragm wall and a method for constructing basement exterior walls and floors by using the prefabricated underground diaphragm wall.

Background technique

With the advancement of foundation pit support technology and the development of building underground structure technology, a kind of underground diaphragm wall integrating foundation pit surrounding pile wall and basement exterior wall has emerged. The supporting and water retaining functions of the pit enclosure pile wall to the foundation pit can also be directly used as the basement exterior wall to support the upper structure of the building. After the wall is constructed, there is no need to separately construct the foundation pit enclosure protection pile wall and the basement exterior wall. Therefore, the construction period can be greatly shortened, and because the basement outdoor wall and the foundation pit surrounding pile wall are integrated, the usable area of the underground structure is expanded and the area occupied by the construction site is reduced, which is in line with the increasingly tense urban land area.

The construction method of the underground diaphragm wall in the prior art is as follows: first drill the pile holes, then dig installation grooves matching the shape of the wall body, then put the pile foundation reinforcement cage into the pile holes and put the wall reinforcement cage into the installation grooves , and then pour and pound the wall and pile foundation concrete in one piece. There is a drawback in the construction method of the prior art: due to the large volume of the whole wall, the amount of poured concrete is large, the hardening speed of the concrete is too slow, and the construction period is too long.

In order to speed up the construction speed and shorten the construction period, someone proposed a construction idea of prefabricating the underground diaphragm wall first, that is, prefabricating the underground diaphragm wall first, and then directly transporting the prefabricated and fully hardened outer wall to the construction site, and then transporting it to the construction site. It is directly hoisted into the installation tank, so naturally there is no need to wait for the concrete of the underground continuous wall to harden, which greatly shortens the construction period. However, the volume of the underground diaphragm wall is huge, and it is naturally impossible to carry and lift the complete underground diaphragm wall. Therefore, only the wall monomer can be prefabricated, and the wall monomer can be hoisted into the installation groove to form a whole underground diaphragm wall. This idea cannot be realized due to an insurmountable technical problem: that is, the longitudinal connection between the wall monomers, that is, the height direction, and the longitudinal connection between the continuous wall and the pile foundation cannot be realized. The shear strength and longitudinal bearing capacity are not enough to bear the lateral pressure of the soil, nor can it support the longitudinal pressure of the superstructure of the building. Moreover, there is also a defect in this idea: since the underground diaphragm wall is prefabricated, when the basement floor slab needs to be poured and rammed, the concrete of the underground diaphragm wall at the same level as the floor slab must be knocked out to expose the steel bars, and then the floor steel bars and the underground diaphragm wall The steel bars are butt-connected, and finally the concrete for the floor slab is poured, that is, the concrete for the underground diaphragm wall must be knocked out for the construction of the floor slab concrete. The process is cumbersome and may even easily cause damage to the structure of the underground diaphragm wall.

Contents of the invention

A technical problem to be solved by the present invention is to provide a prefabricated underground diaphragm wall that can speed up the construction speed, shorten the construction period, have good lateral shear and longitudinal compressive bearing capacity, and do not need to knock off the concrete of the diaphragm wall when constructing the floor slab.

A technical solution of the present invention is to provide a prefabricated underground continuous wall, which includes a plurality of wall units and a plurality of pile foundations, and each wall unit has a plurality of prestressed holes and a plurality of non-prestressed holes in the longitudinal direction. Stress holes, the horizontal reinforcement of each wall monomer protrudes from the left and right sides of the wall monomer, and multiple wall monomers are stacked vertically to form a row of walls, and a prestressed hole runs through all the wall monomers of each row of walls. Prestressed steel bar with casing, the lower end of the prestressed steel bar and the lower end of the casing are anchored in the concrete of the pile foundation, the prestressed steel bar tensions all the wall monomers and pile foundations of the row of walls, and the prestressed holes are filled Full of cement slurry, a non-prestressed steel bar runs through the non-prestressed holes of all the wall monomers in each row of walls, and the non-prestressed holes are also filled with cement slurry; between every two adjacent wall rows Concrete junction, the concrete junction is equipped with a reinforcement cage for the junction, and the reinforcement cage of the junction is butt-fixed with the horizontal reinforcement extending into the concrete junction of the wall rows on the left and right sides; the inner surface of each wall monomer is provided with a horizontal There is a row of multiple reserved holes and a pre-embedded steel plate at the bottom of the horizontal groove. Butt fixed connecting steel bars, screw a sealing plate to cover the embedded steel plate and the reserved hole horizontally in the groove.

Another technical problem to be solved by the present invention is to provide a construction basement exterior wall and floor slab that can speed up the construction speed, shorten the construction period, have good lateral shear resistance and longitudinal compressive bearing capacity, and do not need to knock off the concrete of the underground diaphragm wall when constructing the floor slab. Methods.

Another technical solution of the present invention is to provide a method for constructing basement exterior walls and floor slabs, the steps of which include:

a. Dig the installation groove and drill multiple pile holes, the pile holes are located at the bottom of the installation groove;

b. Insert a pile foundation reinforcement cage and a prestressed steel bar with casing into each pile hole, and inject grout into the pile hole;

c. Stack multiple wall monomers vertically to form multiple wall columns and put them into the installation groove. Each wall column is formed by stacking multiple wall monomers from bottom to top, and the pile foundation under each wall column The prestressed steel bars and sleeves anchored in the middle pass through the prestressed holes of all the wall monomers of the wall column, and then insert the non-prestressed steel bars into the non-prestressed holes of all the wall monomers of each wall column, and then insert the non-prestressed steel bars into each wall Grouting in the prestressed holes and non-prestressed holes of the column, after the concrete is dry and hard, the prestressed steel bars are tensioned, so that multiple longitudinally superimposed wall monomers form an integral wall column;

d. Insert the reinforcement cage of the joint into the gap between every two adjacent wall columns, and the protruding transverse reinforcement on the side of each wall monomer of the wall column is docked and fixed with the reinforcement cage of the joint, and then grouting in the gap , so that it forms the concrete junction between the wall columns, so that multiple wall columns form an integral underground continuous wall;

e. Pour and tamp the floor slab concrete on the top floor of the basement at the top level of the underground diaphragm wall, and reserve work holes for excavation and excavation on the floor slab of the top floor of the basement;

f. Excavate the soil in the underground diaphragm wall until it reaches the level of the next basement floor, and remove the sealing plate of the wall unit at this level, so that the reserved holes and pre-embedded steel plates on the inner surface of the wall unit are exposed. Weld the angle steel on the pre-embedded steel plate, then lay the reinforcement cage of the floor and extend the horizontal reinforcement of the reinforcement cage of the floor into the reserved hole to connect with the connection reinforcement in the reserved hole, then pour the floor concrete and place the reserved hole Fill it with grout and anchor the horizontal steel plate of the angle steel in the concrete. When pouring and tamping the floor slab, also reserve a working hole on the floor slab for continued digging and excavation;

g. Step f is repeated until the floor slab construction of the bottom floor of the basement is completed.

Compared with the prior art, the prefabricated underground diaphragm wall and the method for constructing basement exterior wall and floor slab of the present invention have the following advantages and effects:

First of all, the main structure of the underground diaphragm wall, that is, each wall unit is prefabricated, and only the connecting parts are grouted on site. In this way, the amount of grouting on site is greatly reduced, so the concrete hardens quickly and the construction speed is greatly accelerated. Shorten the construction period; secondly, from the longitudinal direction, the prestressed steel bars will tension the concrete of multiple wall monomers and pile foundations of the same wall row in the longitudinal direction, which improves the lateral shear and longitudinal compressive bearing capacity of the wall row, and The prestressed steel bars and cement slurry in the prestressed hole form a longitudinal prestressed concrete connection column, while the non-prestressed steel reinforcement and cement slurry in a non-prestressed hole form a longitudinal non-prestressed concrete connection column, and the prestressed concrete connection column and The non-prestressed concrete connection column further strengthens multiple wall units and pile foundations into an integral wall row, further increasing its transverse shear and longitudinal compressive bearing capacity, which overcomes the gap between the wall units and the wall units. The technical problem that the longitudinal connection and the longitudinal connection between the continuous wall and the pile foundation cannot be realized; thirdly, through the joint reinforcement cage in the concrete joint, the horizontal reinforcement of the wall rows on the left and right sides is butt-fixed, so that each wall row is horizontally connected Integral continuous underground wall; moreover, when constructing the floor slab, it is not necessary to knock off the concrete on the wall as in the prior art, but remove the sealing plate to expose the reserved holes and the connecting steel bars in the reserved holes, and then install the connecting steel bars It is docked and fixed with the floor reinforcement cage, and the floor concrete can be poured and rammed. The floor construction process is convenient and fast, and the connection between the floor and the underground diaphragm wall is firm and reliable. Moreover, the angle steel is welded on the pre-embedded steel plate, and the angle steel is anchored in the floor concrete. In this way, the connection between the floor slab and the underground diaphragm wall is strengthened, and the shear strength of the connection position is improved.

Description of drawings

Fig. 1 is a schematic diagram of the front view of the prefabricated underground continuous wall and floor slab of the present invention.

Fig. 2 is a schematic diagram of the front view of the wall unit of the prefabricated underground continuous wall of the present invention.

Fig. 3 is a frontal sectional structural schematic diagram of the wall row of the prefabricated underground continuous wall of the present invention.

Fig. 4 is an enlarged frontal cross-sectional structural schematic diagram of the joint between the prefabricated underground continuous wall and the floor slab of the present invention.

Fig. 5 is a top view structural diagram of the prefabricated underground continuous wall of the present invention.

As shown in the figure 1. Wall monomer, 2. Pile foundation, 3. Prestressed hole, 4. Non-prestressed hole, 5. Transverse reinforcement, 6. Sleeve, 7. Prestressed reinforcement, 8. Non-prestressed reinforcement , 9. Concrete joint, 10. Joint reinforcement cage, 11. Horizontal groove, 12. Reserved hole, 13. Embedded steel plate, 14. Connecting steel bar, 15. Sealing plate, 16. Pile hole, 17. Installation groove, 18, floor slab, 19, operation hole, 20, angle steel, 21, horizontally to reinforcing bar.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5, the prefabricated underground continuous wall of the present invention includes a plurality of wall monomers 1 and a plurality of pile foundations 2. Each wall unit 1 runs through a plurality of prestressed holes 3 and a plurality of non-prestressed holes 4 in the longitudinal direction, and the transverse reinforcement 5 of each wall unit 1 protrudes from the left and right sides of the wall unit 1 . A plurality of wall monomers 1 are stacked vertically to form a wall row, and a prestressed steel bar 7 with a sleeve 6 runs through the prestressed hole 3 of all the wall monomers 1 in each wall row, and the lower end of the prestressed steel bar 7 and the sleeve The lower ends of the pipes 6 are all anchored in the concrete of the pile foundation 2, the prestressed steel bar 7 tensions all the wall monomers 1 and the pile foundation 2 of the row of walls, and the prestressed hole 3 is filled with cement slurry. A non-prestressed steel bar 8 runs through the non-prestressed holes 4 of all the wall monomers 1 of each row of walls, and the non-prestressed holes 4 are also filled with cement slurry. A concrete junction 9 is provided between every two adjacent wall rows, and a junction reinforcement cage 10 is provided in the concrete junction 9, and the junction reinforcement cage 10 and the wall rows on the left and right sides extend into the concrete junction 9. Horizontal reinforcing bars 5 are butt-jointed and fixed. Specifically, the right side of each wall unit 1 of the wall column on the left side of the concrete junction 9 protrudes from the transverse reinforcement 5, and the transverse reinforcement 5 is docked and fixed with the reinforcement cage 10 of the junction; A transverse steel bar 5 protrudes from the left side of each wall unit 1 of the right wall row, and the transverse steel bar 5 is docked and fixed with the reinforcement cage 10 at the junction. The inner surface of each wall unit 1 is provided with a horizontal groove 11 , and the bottom of the horizontal groove 11 is provided with a row of multiple reserved holes 12 and a pre-embedded steel plate 13 . A plurality of reserved holes 12 are horizontally arranged in a row, and the embedded steel plate 13 is located below the row of reserved holes 12 . Each reserved hole 12 is provided with a connecting steel bar 14 that is docked and fixed with the reinforcement cage of the wall unit 1 . A sealing plate 15 for covering the pre-embedded steel plate 13 and the reserved hole 12 is screwed in the groove 11 horizontally. Specifically, the bottom of the horizontal groove 11 is pre-embedded with an embedded part with an internal threaded hole, and the screw passes through the through hole of the sealing plate 15 and is screwed into the internal threaded hole of the embedded part.

The method for constructing basement exterior walls and floor slabs of the present invention, that is, utilizing the prefabricated underground diaphragm wall of the present invention to construct the method for basement exterior walls and floor slabs, it comprises the following steps:

a. Dig the installation groove 17 and drill a plurality of pile holes 16, the pile holes 16 are located at the bottom of the installation groove 17.

b, insert pile foundation 2 reinforcement cages and a prestressed steel bar 7 with casing 6 in each pile hole 16, and grout to pile hole 16, like this, prestressed steel bar 7 and casing 6 are all anchored in Inside the pile foundation 2, and the lower end of the prestressed steel bar 7 forms an anchor end.

c. Stack multiple wall monomers 1 vertically into multiple wall columns and put them into the installation groove 17. Each wall column is formed by stacking multiple wall monomers 1 from bottom to top, and place the bottom of each wall column The prestressed steel bars 7 and sleeves 6 anchored in the pile foundation 2 pass through the prestressed holes 3 of all the wall monomers 1 of the wall row, and then enter the non-prestressed holes 4 of all the wall monomers 1 of each wall row Insert non-prestressed steel bars 8, and then grout into the prestressed holes 3 and non-prestressed holes 4 of each wall column. After the concrete is dry and hard, tension the prestressed steel bars 7. In this way, multiple vertically superimposed wall monomers 1 forms an integral wall column.

d. Insert the joint reinforcement cage 10 into the gap between every two adjacent wall columns, and the protruding transverse reinforcement 5 on the side of each wall monomer 1 of the wall column is docked and fixed with the joint reinforcement cage 10, and then Grout is injected into the gap to form a concrete junction 9 between the wall columns, so that a plurality of wall columns form an integral underground continuous wall.

e. Pour and tamp the floor slab 18 concrete on the top floor of the basement at the top elevation of the underground continuous wall, and the vertical reinforcement of the reinforcement cage of a wall monomer 1 at the top of each wall column protrudes from the top surface of the wall monomer 1, laying the basement When the top floor slab 18 is the floor slab 18 at the same level as the ground, connect the reinforcement cage of the floor slab 18 with the protruding vertical reinforcement on the top surface of the uppermost wall unit 1 of the wall row, and set up a formwork to pour the top floor slab 18 Concrete. On the floor slab 18 of the top floor of the basement, reserve the working hole 19 of digging and unearthed, and this working hole 19 will be filled up after the construction of the basement structure is completed.

f. Multiple underground diaphragm walls form the edge of the foundation pit, and the soil in the underground diaphragm wall is dug down to form the foundation pit. Excavate the soil in the underground diaphragm wall until it reaches the level of the next basement floor 18, remove the sealing plate 15 of the wall unit 1 at this level, so that the reserved hole 12 on the inner surface of the wall unit 1 and the reserved The buried steel plate 13 is exposed, and the angle steel 20 is welded on the pre-embedded steel plate 13, and then the reinforcement cage of the floor 18 is laid, and the horizontal direction of the reinforcement cage of the floor 18 is extended to the reinforcement 21 into the reserved hole 12 and the connecting reinforcement in the reserved hole 12 14 docking, pouring and pounding the floor slab 18 concrete again and filling the reserved hole 12 with grout and anchoring the horizontal steel plate of the angle steel 20 in the concrete. Unearthed working hole 19.

g, repeat step f, until the construction of the floor slab 18 of the bottom of the basement is completed, when the floor slab 18 of the bottom floor is poured and rammed, there is no need to stay the operation hole 19.

Claims (2)

1. A prefabricated underground continuous wall is characterized in that: it comprises a plurality of wall monomers (1) and a plurality of pile foundations (2), and each wall monomer (1) has a plurality of prestressed holes vertically (3) and a plurality of non-prestressed holes (4), the transverse reinforcement (5) of each wall monomer (1) protrudes from the left and right sides of the wall monomer (1), and the longitudinal direction of multiple wall monomers (1) A series of wall columns are superimposed, and a prestressed steel bar (7) with a sleeve (6) runs through the prestressed holes (3) of all the wall monomers (1) of each wall column, and the prestressed steel bar (7) Both the lower end and the lower end of the casing (6) are anchored in the concrete of the pile foundation (2), and the prestressed steel bar (7) tensions and prestresses all the wall elements (1) and pile foundation (2) of the row of walls. The hole (3) is filled with cement slurry, and a non-prestressed steel bar (8) runs through the non-prestressed hole (4) of all the wall monomers (1) of each row of walls, and the non-prestressed hole (4) It is also filled with cement slurry; a concrete junction (9) is provided between every two adjacent wall columns, and a junction reinforcement cage (10) is provided in the concrete junction (9), and the junction reinforcement cage (10) is connected to the The horizontal steel bars (5) extending into the concrete junction (9) of the wall columns on the left and right sides are docked and fixed; the inner surface of each wall monomer (1) is provided with a horizontal groove (11), and the horizontal groove (11) The bottom of the tank is provided with a row of multiple reserved holes (12) and a pre-embedded steel plate (13), the pre-embedded steel plate (13) is located below a row of reserved holes (12), and each reserved hole (12 ) is provided with a connecting steel bar (14) that is docked and fixed with the reinforcement cage of the wall monomer (1), and a piece of steel bar (14) is screwed in the horizontal groove (11) to cover the pre-embedded steel plate (13) and the reserved hole (12). Sealing plate (15). 2. A method for constructing basement exterior walls and floor slabs, characterized in that: it may further comprise the steps: a, dig the installation groove (17) and drill a plurality of pile holes (16), the pile holes (16) are positioned at the groove bottom of the installation groove (17); B, insert pile foundation (2) reinforcement cage and a prestressed steel bar (7) with casing (6) in each pile hole (16), and grout to pile hole (16); c. Vertically superimpose multiple wall monomers (1) into multiple wall columns and put them into the installation groove (17), each wall column is formed by stacking multiple wall monomers (1) from bottom to top, and Pass the prestressed steel bars (7) and sleeves (6) anchored in the pile foundation (2) below each wall row through the prestressed holes (3) of all the wall monomers (1) of the wall row, and then to each Insert non-prestressed steel bars (8) into the non-prestressed holes (4) of all wall monomers (1) of each wall column, and then insert them into the prestressed holes (3) and non-prestressed holes (4) of each wall column. After grouting, the prestressed steel bar (7) is tensioned after the concrete is dried and hardened, so that a plurality of vertically stacked wall monomers (1) form an integral wall row; d. Insert the joint reinforcement cage (10) into the gap between every two adjacent wall columns, and the protruding transverse reinforcement (5) on the side of each wall monomer (1) of the wall column and the joint reinforcement Cages (10) are docked and fixed, and then grouted into the gap to form a concrete joint (9) between the wall rows, so that multiple wall rows form an integral underground continuous wall; E. Pour concrete on the floor slab (18) of the top floor of the basement at the top elevation of the underground diaphragm wall, and reserve the excavated and unearthed operation holes (19) on the floor slab (18) of the top floor of the basement; F, excavate the soil body in the underground diaphragm wall until the elevation of the next basement floor (18) is dug down, and the sealing plate (15) of the wall monomer (1) of this elevation is removed, so that the wall monomer (1 ) on the inner surface of the reserved hole (12) and the embedded steel plate (13) are exposed, the angle steel (20) is welded on the embedded steel plate (13), and then the reinforcement cage of the floor (18) is laid and the floor (18) The horizontal reinforcing bar (21) of the reinforcing cage stretches into the reserved hole (12) and connects the connecting reinforcing bar (14) in the reserved hole (12) butt joint, then pours and tamps the floor slab (18) concrete and injects the reserved hole (12) The slurry is filled and the horizontal steel plate of the angle steel (20) is also anchored in the concrete. When the floor slab (18) is poured and rammed, the operation hole (19) for continuing to dig and unearthed is also reserved on the floor slab (18); g, repeat step f, until the floor slab (18) construction of the bottom floor of the basement is completed.