A bottom-expanding foundation pit assembled retaining wall device and sinking installation method

Abstract

A kind of bottom expansion foundation pit assembly type retaining wall device and sinking installation method, it mainly includes arc structure, transition connecting sheet;Multiple arc structure is spliced and fixed into a section of retaining wall ring body, and is stacked by the transition connecting sheet clamping between adjacent retaining wall ring body;Wherein, the arc structure on the bottom layer is opened with construction hole, and construction hole is used for artificial access bottom expansion part of foundation pit.The bottom expansion foundation pit assembly type retaining wall device and sinking installation method provided by the present application can be recycled, and cost is saved;It is suitable in bottom expansion foundation pit simultaneously.

Description

TECHNICAL FIELD

[0001] The present application relates to a foundation pit assembled retaining wall, in particular to an expanded bottom foundation pit assembled retaining wall device and sinking installation method. BACKGROUND

[0002] In the process of foundation pit excavation in mountain rescue engineering, it is the key prerequisite to quickly and safely form a stable expanded bottom foundation pit hole meeting the design requirements to complete the construction of foundation piles such as power transmission line tower foundation and bridge base. The expanded bottom foundation pit hole in mountainous areas is mostly excavated manually due to traffic conditions, and the hole wall collapse and soil collapse are prone to occur during the hole forming process, which has great safety hazards. In order to ensure the safety of the foundation construction personnel and the integrity of the foundation pit shape, a retaining wall structure needs to be set up to stabilize the excavated foundation pit hole wall when the foundation is formed, and then the excavation of the foundation pit is continued.

[0003] At present, the conventional foundation pit support form can use cast-in-place reinforced concrete retaining wall structure to support the foundation pit hole wall or replace the conventional cast-in-place reinforced concrete retaining wall with assembled steel-concrete retaining wall and assembled metal retaining wall. The first way greatly delays the construction time of the foundation pit rescue engineering, and the second way is processed in the factory, assembled on site, and lowered into the foundation pit to be poured together with the foundation pile. Although it avoids the formwork, pouring and curing links of cast-in-place retaining wall, effectively shortens the construction period, but such assembled retaining wall cannot be recycled and reused after the foundation pit is poured with concrete, has high construction cost and poor economy; and for the expanded bottom foundation pit excavated manually, the existing assembled retaining wall does not provide enough space for the construction personnel to excavate the expanded bottom part around the bottom of the pit on the bottom layer retaining wall, and has poor applicability in the expanded bottom foundation pit. SUMMARY

[0004] The technical problem to be solved by the present application is to provide an expanded bottom foundation pit assembled retaining wall device and sinking installation method, which can be recycled, save the cost of retaining wall device, and is also applicable in the expanded bottom foundation pit.

[0005] To solve the above technical problems, the technical solution adopted by the present application is:

[0006] An expanded bottom foundation pit assembled retaining wall device, comprising an arc-shaped structure body and a transition connecting piece; a plurality of arc-shaped structure bodies are spliced and fixed into a retaining wall ring body, and adjacent retaining wall ring bodies are stacked through the transition connecting piece; wherein a construction hole is opened on the bottommost arc-shaped structure body, and the construction hole is used for manual entry into the expanded bottom part of the foundation pit.

[0007] The arc-shaped structure includes a first arc-shaped structure, a second arc-shaped structure and a third arc-shaped structure, and the first arc-shaped structure, the second arc-shaped structure and the third arc-shaped structure are respectively provided with convex connecting parts and concave connecting parts, a plurality of first arc-shaped structures are spliced to form a solid retaining wall ring body through the convex connecting parts and the concave connecting parts, a plurality of second arc-shaped structures are spliced to form a multi-hole retaining wall ring body through the convex connecting parts and the concave connecting parts, and a plurality of third arc-shaped structures are spliced to form a bottom layer retaining wall ring body through the convex connecting parts and the concave connecting parts.

[0008] The first arc-shaped structure is fixed with a lifting hook on the outer side.

[0009] The bottom layer retaining wall ring body and the multi-hole retaining wall ring body are sequentially stacked on the bottom of the foundation pit from bottom to top, and a plurality of solid retaining wall ring bodies are sequentially stacked above the multi-hole retaining wall ring body.

[0010] A construction hole is formed on the bottom layer retaining wall ring body, and a plurality of through holes are arranged on the multi-hole retaining wall ring body.

[0011] The convex connecting parts and the concave connecting parts are connected through a plurality of bolts.

[0012] The transition connecting piece is in H-shaped cross section, and the upper and lower grooves of the transition connecting piece are correspondingly clamped and attached to the upper and lower arc-shaped structures.

[0013] A sinking installation method of an expanded bottom foundation pit assembly type retaining wall device, comprising the following steps:

[0014] Step 1), excavate a circular expanded bottom foundation pit, the excavation depth of the first section of soil body should not exceed the height of one supporting section of the assembly type retaining wall, so as to ensure that the first section of retaining wall ring body is 0.1 m-0.2 m higher than the ground after installation, so as to prevent sundries from falling into the foundation pit, and stop excavating the foundation pit when the excavation depth of the first section of soil body reaches the specified height;

[0015] Step 2), the construction personnel assemble the bottom layer retaining wall ring body on the ground, and vertically place it on the excavated pit bottom by lifting or manual method;

[0016] Step 3), continue to excavate the circular expanded bottom foundation pit, assemble the multi-hole retaining wall ring body on the ground when the excavation depth reaches the height of one supporting section of the assembly type retaining wall, tie a lifting steel wire rope on the hooks of the three second arc-shaped structures respectively, place a plurality of transition connecting pieces on the surface of the bottom layer retaining wall ring body at equal intervals before lifting the multi-hole retaining wall ring body, then vertically lift the multi-hole retaining wall ring body to the upper side of the foundation pit by means of the three lifting steel wire ropes, stack it in the transition connecting pieces of the bottom layer retaining wall ring body, and remove the lifting steel wire ropes;

[0017] Step 4, continue to dig the circular foundation pit downward, when the excavation depth reaches the height of a support segment of the assembled retaining wall, assemble the first segment solid retaining wall ring body on the ground, and bind a disassembly steel wire rope and a hoisting steel wire rope on the hooks of each first arc-shaped structure body. Before hoisting, place several transition connecting pieces on the upper ring surface of the multi-hole retaining wall ring body, hoist the first segment solid retaining wall ring body from top to bottom and stack it in the transition connecting pieces of the multi-hole retaining wall ring body, at the same time, remove the three hoisting steel wire ropes on the first segment solid retaining wall ring body, and keep the three disassembly steel wire ropes bound on the first segment solid retaining wall ring body;

[0018] Step 5, continue to dig downward, stop digging the foundation pit every time a segment retaining wall ring body height is reached, and repeat the steps to stack the solid retaining wall ring body of the new segment in the transition connecting pieces of the previous segment solid retaining wall ring body. As the foundation pit soil is continuously excavated, the installed assembled retaining wall ring body sinks segment by segment under the action of its own weight, and the retaining wall ring body at the foundation pit opening is always kept 0.1 m-0.2 m higher than the ground until the excavation reaches the design depth of the foundation pit;

[0019] Step 6, when the excavation reaches the design depth of the foundation pit, excavate the foundation pit expansion hole by manually excavating the foundation pit expansion hole through the construction hole reserved on the bottom layer retaining wall ring body at the bottom of the foundation pit;

[0020] Step 7, after pouring concrete in the expanded foundation pit, lift the solid retaining wall ring body to the ground through the disassembly steel wire rope, clean it and disassemble it into arc-shaped structure bodies for subsequent foundation pit excavation operations.

[0021] The assembled retaining wall device for expanded foundation pit and the sinking installation method have the following technical effects:

[0022] 1, the three arc-shaped structure bodies are spliced into a circular pipe-shaped retaining wall ring body through the convex connecting part, the concave connecting part and the bolts, and the retaining wall ring bodies of adjacent segments are vertically spliced through the H-shaped transition connecting piece, so that the entire retaining wall device is easy to assemble and the foundation pit operation time is shortened. The arc-shaped structure body and the transition connecting piece are made of high-strength material, the load-bearing performance of the retaining wall ring body is good, and the construction safety is high.

[0023] 2, in the case of vertical splicing of each segment retaining wall ring body using the transition connecting piece, when the foundation pit concrete pouring is completed, each segment retaining wall ring body can be lifted to the ground through the disassembly steel wire rope bound at the hook of the retaining wall ring body, realizing the recycling and cyclic use of the retaining wall, reducing the construction cost of the pile foundation, and being economical.

[0024] 3), the bottom layer of the wall ring body reserves a certain space, which can meet the excavation demand of the base pit expansion bottom part, and has strong applicability. When pouring the concrete pile body of the expansion bottom base pit, the through holes on the multi-hole wall ring body and the bottom layer of the wall ring body can ensure that the concrete slurry is better poured into the expansion bottom of the base pit, and is poured densely, thereby ensuring the vertical bearing capacity of the expansion bottom foundation. BRIEF DESCRIPTION OF DRAWINGS

[0025] The application will be further described below in combination with the drawings and embodiments:

[0026] Figure 1 It is a structure schematic view of the first arc-shaped structure body in the application.

[0027] Figure 2 It is a structure schematic view of the second arc-shaped structure body in the application.

[0028] Figure 3 It is a structure schematic view of the third arc-shaped structure body in the application.

[0029] Figure 4 It is a top view of a section wall ring body in the application.

[0030] Figure 5 It is a sectional view of a transition connecting piece in the application.

[0031] Figure 6 It is a connection schematic view of the transition connecting piece and upper and lower layers of sections in the application.

[0032] Figure 7 It is an installation schematic view of a layer wall ring body in the application.

[0033] Figure 8 It is an installation schematic view of a multi-hole wall ring body in the application.

[0034] Figure 9 It is a schematic view of the installation of the expansion bottom base pit assembled wall in the application.

[0035] Figure 10 It is a recycling schematic view of the wall ring body in the application.

[0036] In the figure: the first arc-shaped structure body 1, the second arc-shaped structure body 2, the third arc-shaped structure body 3, the transition connecting piece 4, the bottom layer of the wall ring body 5, the multi-hole wall ring body 6, the solid wall ring body 7, the dismounting steel wire rope 8, the convex connecting part 9, the concave connecting part 10, the bolt hole 11, the lifting hook 12, the through hole 13, the construction hole 14, the upper layer of sections 15, the lower layer of sections 16, the unexcavated soil body 17, the concrete 18. DETAILED DESCRIPTION

[0037] As Figures 1-8As shown, a prefabricated retaining wall device for an expanded-bottom foundation pit includes a first arc-shaped structure 1, a second arc-shaped structure 2, a third arc-shaped structure 3, and a transition connecting piece 4. The first arc-shaped structure 1, the second arc-shaped structure 2, and the third arc-shaped structure 3 have essentially the same external structure, all being arc-shaped plates. A convex connecting portion 9 is reserved at one end of each arc-shaped plate, and a concave connecting portion 10 matching the convex connecting portion 9 is reserved at the other end. Several through bolt holes 11 are arranged at equal intervals on the convex connecting portion 9 and the concave connecting portion 10. The three first arc-shaped structures 1 are sequentially spliced ​​and bolted together to form a solid retaining wall ring 7; the three second arc-shaped structures 2 are sequentially spliced ​​and bolted together to form a porous retaining wall ring 6; and the three third arc-shaped structures 3 are sequentially spliced ​​and bolted together to form a bottom retaining wall ring 5. The bottom protective ring 5, the porous protective ring 6, and the solid protective ring 7 all have circular cross-sections. The bottom protective ring 5, the porous protective ring 6, and the solid protective ring 7 each constitute a segment of the protective wall device. The protective rings of the upper segment and the protective rings of the lower segment are stacked and connected by an "H"-shaped transition connecting piece 4.

[0038] In addition, such as Figure 1 As shown, a hook 12 is fixed on the outside of the first arc-shaped structure 1. The hook 12 is used to connect with the disassembly wire rope 8.

[0039] like Figures 2-3 As shown, multiple through holes 13 are reserved on the second arc-shaped structure 2, while construction holes 14 are reserved on the third arc-shaped structure 3. The construction holes 14 can realize manual excavation and concrete pouring of the expanded bottom part of the foundation pit.

[0040] like Figure 6 As shown, the upper and lower slots of the "H"-shaped transition connecting piece 4 match the curvature of the arc-shaped sidewall of the protective ring to ensure a close fit.

[0041] A method for sinking and installing a prefabricated retaining wall device for an expanded-bottom foundation pit includes the following steps:

[0042] Step 1), as Figure 7 As shown, when excavating a circular, wide-bottomed foundation pit, the excavation depth of the first section of soil should not exceed the height of one support segment of the prefabricated retaining wall. Ensure that the first retaining wall ring is 0.1 m - 0.2 m above the ground after installation to prevent debris from falling into the foundation pit. When the excavation depth of the first section of soil reaches the specified height, stop excavating the foundation pit.

[0043] Step 2), as Figure 7 As shown, the construction workers assembled the bottom retaining ring 5 on the ground and placed it vertically at the bottom of the excavated pit by hoisting or by hand.

[0044] Step 3), as Figure 8As shown, continue to dig the circular foundation pit downward, when the excavation depth reaches the height of one supporting segment of the assembled retaining wall, assemble the first segment solid retaining wall ring body 7 on the ground, and bind a disassembly steel wire rope and a hoisting steel wire rope on the hook of each first arc-shaped structure 1. Before hoisting, place several transition connecting pieces 4 on the upper ring surface of the multi-hole retaining wall ring body 6, and then hoist the first segment solid retaining wall ring body 7 from top to bottom into the transition connecting pieces 4 of the multi-hole retaining wall ring body 6 by means of three hoisting steel wire ropes, and remove the three hoisting steel wire ropes on the first segment solid retaining wall ring body 7, and retain the three disassembly steel wire ropes bound on the first segment solid retaining wall ring body 7.

[0045] Step 4), as shown in Figure 9 As shown, continue to dig the circular foundation pit downward, when the excavation depth reaches the height of one supporting segment of the assembled retaining wall, assemble the first segment solid retaining wall ring body 7 on the ground, and bind a disassembly steel wire rope and a hoisting steel wire rope on the hook of each first arc-shaped structure 1. Before hoisting, place several transition connecting pieces 4 on the upper ring surface of the multi-hole retaining wall ring body 6, and then hoist the first segment solid retaining wall ring body 7 from top to bottom into the transition connecting pieces 4 of the multi-hole retaining wall ring body 6 by means of three hoisting steel wire ropes, and remove the three hoisting steel wire ropes on the first segment solid retaining wall ring body 7, and retain the three disassembly steel wire ropes bound on the first segment solid retaining wall ring body 7.

[0046] Step 5), continue to dig downward, stop digging the foundation pit every time a segment retaining wall ring body height is excavated, repeat step (4), and sequentially stack the solid retaining wall ring body 7 of the new segment into the transition connecting piece 4 of the solid retaining wall ring body 7 of the previous segment. As the soil of the foundation pit is continuously excavated, the assembled retaining wall ring body sinks one segment at a time under the action of its own weight, and the retaining wall ring body at the foundation pit opening is always 0.1 m-0.2 m higher than the ground, until the excavation reaches the design depth of the foundation pit.

[0047] Step 6), when the excavation reaches the design depth of the foundation pit, Figure 9 As shown in a, the foundation pit is excavated by artificial through the construction hole 14.

[0048] Step 7), after pouring concrete in the expanded foundation pit, lift the solid retaining wall ring body 7 to the ground through the disassembly steel wire rope 8, and then disassemble it into arc-shaped structures for subsequent foundation pit excavation operations.

Claims

1. A method for installing a bottom-expanded foundation pit assembled retaining wall, characterized in that: The application relates to an expansion bottom foundation assembly type retaining wall device, which comprises arc-shaped structures and transition connecting plates (4); a plurality of arc-shaped structures are fixedly connected to form a retaining wall ring body, and adjacent retaining wall ring bodies are connected through the transition connecting plates (4); wherein a construction hole (14) is formed in the bottommost arc-shaped structure, and the construction hole (14) is used for enabling workers to enter the expansion bottom part of the foundation pit; The arc-shaped structure comprises first arc-shaped structures (1), second arc-shaped structures (2) and third arc-shaped structures (3), the first arc-shaped structures (1), the second arc-shaped structures (2) and the third arc-shaped structures (3) are respectively provided with convex connecting parts (9) and concave connecting parts (10) on the left and right sides, a plurality of the first arc-shaped structures (1) are connected through the convex connecting parts (9) and the concave connecting parts (10) to form a solid retaining wall ring body (7), a plurality of the second arc-shaped structures (2) are connected through the convex connecting parts (9) and the concave connecting parts (10) to form a multi-hole retaining wall ring body (6), and a plurality of the third arc-shaped structures (3) are connected through the convex connecting parts (9) and the concave connecting parts (10) to form a bottom layer retaining wall ring body (5); The first arc-shaped structure (1) is fixed with a lifting hook (12) on the outer side; the lifting hook (12) is used for being connected with a dismounting steel wire rope (8); The bottom layer retaining wall ring body (5) and the multi-hole retaining wall ring body (6) are sequentially stacked on the bottom of the foundation pit from bottom to top, and a plurality of the solid retaining wall ring bodies (7) are sequentially stacked above the multi-hole retaining wall ring body (6); The transition connecting plate (4) is in H-shaped cross section, and the upper and lower grooves of the transition connecting plate (4) are correspondingly connected with and attached to the upper and lower arc-shaped structures; The application further discloses an expansion bottom foundation assembly type retaining wall sinking installation method, which comprises the following steps: Step 1), a circular expansion bottom foundation pit is excavated downwards, the excavation depth of the first section of soil body should not exceed the height of one supporting section of the assembly type retaining wall, so that the first retaining wall ring body after installation is 0.1 m-0.2 m higher than the ground, so as to prevent sundries from falling into the foundation pit, and the excavation of the foundation pit is stopped when the excavation depth of the first section of soil body reaches the specified height; Step 2), a construction worker assembles the bottom layer retaining wall ring body (5) on the ground and vertically places the bottom layer retaining wall ring body (5) in the excavated pit bottom through hoisting or manual operation; Step 3), the circular expansion bottom foundation pit is continuously excavated downwards, the multi-hole retaining wall ring body (6) is assembled on the ground when the excavation depth reaches the height of one supporting section of the assembly type retaining wall, one hoisting steel wire rope is bound on the lifting hooks of the three second arc-shaped structures (2) respectively, a plurality of transition connecting plates (4) are equidistantly arranged on the ring surface of the bottom layer retaining wall ring body (5) before the multi-hole retaining wall ring body (6) is hoisted, and then the multi-hole retaining wall ring body (6) is vertically hoisted to the upper side of the foundation pit by means of the three hoisting steel wire ropes, the multi-hole retaining wall ring body (6) is stacked in the transition connecting plates (4) of the bottom layer retaining wall ring body (5), and the hoisting steel wire ropes are removed. Step 4, continue to dig the circular foundation pit downward, when the excavation depth reaches the height of one support segment of the assembled retaining wall, assemble the first segment solid retaining wall ring body (7) on the ground, and bind a disassembly steel wire rope and a hoisting steel wire rope on the hook of each first arc-shaped structure body (1); before hoisting, place several transition connecting pieces (4) on the upper ring surface of the multi-hole retaining wall ring body (6), hoist the first segment solid retaining wall ring body (7) from top to bottom and stack it in the transition connecting piece (4) of the multi-hole retaining wall ring body (6), at the same time, remove the three hoisting steel wire ropes on the first segment solid retaining wall ring body (7), and keep the three disassembly steel wire ropes bound on the first segment solid retaining wall ring body (7); Step 5, continue to dig downward, stop digging the foundation pit every time a segment retaining wall ring body height is excavated, repeat step (4), and stack the solid retaining wall ring body (7) of the new segment in the transition connecting piece (4) of the previous segment solid retaining wall ring body (7) in turn; as the foundation pit soil body is continuously excavated, the installed assembled retaining wall ring body sinks segment by segment under the action of its own weight, and the retaining wall ring body at the foundation pit opening is always kept 0.1 m-0.2 m higher than the ground, until the excavation reaches the design depth of the foundation pit; Step 6, when the excavation reaches the design depth of the foundation pit, excavate the foundation pit expansion part through the construction hole (14) reserved on the bottom layer retaining wall ring body (5) at the bottom of the foundation pit, and excavate the foundation pit expansion hole through the construction hole (14) by artificial; Step 7, after pouring concrete in the expanded foundation pit, lift the solid retaining wall ring body (7) to the ground through the disassembly steel wire rope (8), and after cleaning, disassemble it into arc-shaped structure bodies for subsequent foundation pit excavation operation.

2. The method according to claim 1, wherein the method is characterized by: The construction hole (14) is opened on the bottom layer retaining wall ring body (5), and the multi-hole retaining wall ring body (6) is provided with a plurality of groups of through holes (13).

3. The method according to claim 1, wherein the method is characterized by: The convex connecting part (9) and the concave connecting part (10) are connected by a plurality of groups of bolts. The convex connecting part (9) and the concave connecting part (10) are connected by a plurality of groups of bolts.

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