CN111236245A

CN111236245A - Small foundation pit excavation protection structure and construction method thereof

Info

Publication number: CN111236245A
Application number: CN202010026513.5A
Authority: CN
Inventors: 陈为烈; 彭若宏; 罗建斌; 吴贤淼; 杨鹏; 邓飞; 梁永海; 刘重群; 彭华
Original assignee: China Merchants Harbours Group Co ltd
Current assignee: China Merchants Harbours Group Co ltd
Priority date: 2020-01-10
Filing date: 2020-01-10
Publication date: 2020-06-05
Anticipated expiration: 2040-01-10
Also published as: CN111236245B

Abstract

The invention relates to the technical field of foundation engineering construction, in particular to a small foundation pit excavation protective structure and a construction method thereof. The protective structure is arranged to support the foundation pit, and compared with the existing row pile support, the protective structure has the effect of shortening the whole construction period of the foundation pit.

Description

Small foundation pit excavation protection structure and construction method thereof

Technical Field

The invention relates to the technical field of foundation engineering construction, in particular to a small foundation pit excavation protection structure and a construction method thereof.

Background

At present, along with the rapid development of urbanization in China, the construction in the aspect of municipal administration is gradually improved, and when the municipal construction is carried out in cities, excavation of foundation pits is required firstly.

When the existing foundation pit is excavated, firstly, the construction of row pile support is carried out on the edge of the foundation pit, then, excavating machinery is utilized to excavate earthwork within the design range of the foundation pit, and after the excavation of the foundation pit is finished, then, the row pile is utilized to support the foundation pit, so that the collapse of the foundation pit is avoided.

The above prior art solutions have the following drawbacks: when excavation of a small foundation pit is performed in a building group, due to site limitation, construction is inconvenient when row pile supporting construction is performed, the row pile supporting construction period is long, and the whole construction period of the foundation pit is long.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a small foundation pit excavation protection structure to achieve the purpose of shortening the whole construction period of the foundation pit.

The above object of the present invention is achieved by the following technical solutions:

the utility model provides a little foundation ditch excavation protective structure, protective structure includes the protecting wall, the protecting wall is provided with a plurality of, a plurality of protecting wall ring pit sets up, every side of foundation ditch all sets up the protecting wall, every protecting wall is prefabricated protecting wall, adjacent protecting wall junction is provided with the angle of connection, be provided with coupling assembling between angle of connection and the protecting wall, the protecting groove has been seted up subaerially, protecting groove ring foundation ditch sets up, a plurality of protecting wall all sets up in the foundation ditch, be provided with stabilizing component between the diapire of protecting wall and protecting groove, be provided with the reinforcement component between the lateral wall of protecting wall and protecting groove.

By adopting the technical scheme, when the protective structure is used for excavation, before excavation of the foundation pit, the edge of the foundation pit is measured firstly, then the protective groove is excavated according to the edge of the foundation pit, the protective groove is excavated to the depth of the bottom wall of the foundation pit, then the protective wall is placed in the protective groove, the connecting angle is placed between the adjacent protective walls, the protective wall and the connecting angle are fixedly connected by the connecting assembly, then the protective wall and the bottom wall of the protective groove are fixed by the stabilizing assembly, and the stability of the protective wall during foundation pit supporting is improved when excavation of the foundation pit is carried out; then, excavating the foundation pit, excavating a part of the foundation pit, penetrating the side wall of the protection groove close to the foundation pit to communicate the protection groove with the foundation pit, and then connecting and fixing the protection wall and the side wall of the protection groove far away from the foundation pit by using the reinforcing component to further improve the stability of the protection wall in supporting the foundation pit; compared with the existing row pile support, the protective structure achieves the purpose of shortening the whole construction period of the foundation pit.

The present invention in a preferred example may be further configured to: coupling assembling includes spread groove and connecting block, and the lateral wall at the protecting wall is seted up to the spread groove, and the spread groove runs through the top of protecting wall, connecting block and corner fixed connection, connecting block and spread groove cooperation of pegging graft, connecting block and spread groove sliding connection.

Through adopting above-mentioned technical scheme, use coupling assembling, place the top at the protecting wall with the angle of connection, make connecting block and spread groove align, then promote the angle of connection, make the angle of connection slide in protecting groove (antiskid groove), the angle of connection drives the connecting block and pegs graft in the spread groove, the connecting block slides in the spread groove, utilize the spread groove to the limiting displacement of connecting block, it is fixed with the protecting wall to make the angle of connection, promote the convenience when connecting the angle and being connected with the protecting wall.

The present invention in a preferred example may be further configured to: the spread groove sets up to the spread groove of T type, and the connecting block sets up to the connecting block of T type, and the connecting block suits with the spread groove.

Through adopting above-mentioned technical scheme, utilize the limiting displacement of T type groove to T type piece, when making the connecting block slide in the spread groove, the connecting block is in the spread groove all the time, avoids the angle of connection to drive connecting block and spread groove separation in the slip in-process, promotes the convenience of connecting block when the spread groove slides.

The present invention in a preferred example may be further configured to: the stabilizing assembly comprises a stabilizing hole and a stabilizing rod, the stabilizing hole is formed in the top end of the protective wall and penetrates through the protective wall, the stabilizing rod is in plug-in fit with the stabilizing hole, and one end of the stabilizing rod penetrates through the stabilizing hole and is inserted into the bottom wall of the protective groove.

Through adopting above-mentioned technical scheme, when fixed the diapire of protecting wall and protecting groove, at first insert the one end of stabilizer bar in the stabilizer bar, then promote the stabilizer bar and make the stabilizer bar slide in the stabilizer bar, because the stabilizer bar runs through the protecting wall, so the one end of stabilizer bar and the diapire butt of protecting groove, then the one end that the protecting groove diapire was kept away from to the hammering stabilizer bar, make the one end of stabilizer bar insert in the diapire of protecting groove, it is fixed with the diapire of protecting groove to make the stabilizer bar, utilize the limiting displacement of stabilizer bar to the stabilizer bar, it is fixed along with the stabilizer bar is connected with the diapire of protecting groove to make the protecting wall, promote the stability of protecting.

The present invention in a preferred example may be further configured to: one end of the stabilizer bar inserted into the bottom wall of the protective groove is arranged to be a tip end.

Through adopting above-mentioned technical scheme, the one end of stabilizer bar sets up to most advanced, utilizes the most advanced characteristic of being convenient for to pierce, promotes the convenience when the diapire of protective housing is inserted to the one end of stabilizer bar.

The present invention in a preferred example may be further configured to: the reinforcing assembly comprises a through hole, a reinforcing rod and an end plate, the through hole is formed in the side wall of the protective wall, the through hole is provided with a plurality of, each through hole penetrates through the protective wall, one end of the reinforcing rod is fixedly connected with the end plate, the other end of the reinforcing rod penetrates through the through hole to be inserted into the side wall of the protective groove, and the end plate is abutted to the side wall of the protective wall.

By adopting the technical scheme, when the foundation pit is excavated to a certain degree, part of through holes on the protective wall are leaked, then one end of the reinforcing rod, which is far away from the end plate, is inserted into the through holes, and the reinforcing rod is slid to enable one end of the reinforcing rod to slide in the through holes; then the hammering end plate, because end plate and stiffener fixed connection, so the end plate drives the stiffener and keeps away from in the one end of end plate pierces the lateral wall of protecting bath, perpendicular to end plate and guard plate butt, because the stiffener pierces in the lateral wall of protecting bath, so the stiffener is fixed with the lateral wall of protecting bath, in addition because end plate and stiffener are fixed, and end plate and protecting wall butt, so the protecting wall passes through the stiffener and the lateral wall of end plate and protecting bath is fixed, further promote the stability of protecting wall when as excavation supporting.

The present invention in a preferred example may be further configured to: every the protective wall all includes a plurality of shields, and every shield all sets up stabilizing assembly with the diapire in protective tank, and every shield all sets up the reinforcement unit with the lateral wall in protective tank, is provided with the joint subassembly between the adjacent shield.

By adopting the technical scheme, the protective wall is arranged into the protective plates, and the protective plates are spliced into the protective wall in the protective groove, so that the convenience of hoisting the protective wall into the protective groove is improved; and utilize the joint subassembly to connect the guard plate that links to each other fixedly, promote the connectivity between a plurality of guard plate.

The present invention in a preferred example may be further configured to: the joint subassembly includes joint piece and joint groove, and the joint groove is seted up in one side of guard plate, and one side fixed connection in joint groove is kept away from to joint piece and guard plate, and when adjacent guard plate is connected, the cooperation of pegging graft in joint piece and joint groove.

Through adopting above-mentioned technical scheme, when adjacent guard plate splices in the guard slot, at first place a guard plate in the guard slot, then with another piece guard plate handling to the top of guard plate again, the joint piece and the joint groove of the guard plate that make the handling align, then transfer the guard plate downwards, make the joint board peg graft at the joint inslot, utilize the limiting displacement of joint groove to the joint piece, make adjacent guard plate link together, promote the convenience when guard plate connects.

The second aim of the invention is realized by the following technical scheme:

a construction method for excavating a protective structure in a small foundation pit comprises the following steps:

s1, excavating a protective groove: firstly, measuring the position of a foundation pit, then, using excavating equipment to open a protective groove according to the edge of the foundation pit, and cleaning the bottom wall of the protective groove;

s2, placing a protective wall: hoisting the prefabricated protection plates into the protection grooves, connecting adjacent protection plates through the splicing matching of the clamping blocks and the clamping grooves, connecting and fixing the connecting angles and the protection plates by utilizing the splicing matching of the connecting blocks and the connecting grooves, and sequentially installing the protection plates along the protection grooves to fully fill the protection grooves with the protection plates;

s3, placing a stabilizer bar: inserting one end of the stabilizer bar with a tip end into the stabilizing hole, pushing the stabilizer bar to enable the stabilizer bar to slide in the stabilizing hole, hammering one end of the stabilizer bar away from the tip end when the tip end of the stabilizer bar is abutted to the bottom wall of the protective groove, enabling the tip end of the stabilizer bar to be inserted into the bottom wall of the protective groove, and enabling the protective plate and the protective groove to be fixed by utilizing the limiting effect of the stabilizer bar on the stabilizing hole;

s4, excavating a foundation pit: excavating the foundation pit by using an excavating machine, excavating the side wall of the protective groove close to the foundation pit to enable the protective groove to be communicated with the foundation pit, inserting one end, far away from the end plate, of the reinforcing rod into the through hole when the first through hole is excavated, hammering the end plate to enable one end, far away from the end plate, of the reinforcing rod to be inserted into the side wall of the protective groove, and enabling the end plate to be abutted against the protective plate; and after all the end plates are strengthened in the existing excavation stage, then downward excavation is carried out, then the protection plates are strengthened by utilizing the strengthening rods when another through hole is excavated, and the rest is done until the excavation of the foundation pit is finished.

By adopting the technical scheme, firstly, measurement is carried out, and the accuracy of the excavation position of the protective groove is improved; the bottom wall of the protective groove is cleaned, the bottom wall of the protective groove is ensured to be flat, subsequent protective plates can be conveniently placed, the protective plates are placed in the protective groove in a vertical state, and splicing between adjacent protective plates is facilitated; then, adjacent protection plates are connected together by using the limit between the clamping blocks and the clamping grooves, so that the convenience of assembling the protection plates into the protection wall is improved; the tip of the stabilizer bar is inserted into the bottom wall of the protective groove, so that the convenience of inserting the stabilizer bar is improved, and the protective plate and the protective groove are kept stable by using the limiting performance of the stabilizer bar on the stabilizing hole; when the protective plate is excavated, the protective plate is fixed with the side wall of the protective groove by the reinforcing rod while the protective plate is excavated, so that the stability of the protective plate during supporting is improved; the reinforcement and excavation are performed with cross construction, so that the construction period is shortened, and the purpose of shortening the whole construction period of the foundation pit is achieved.

In summary, the invention includes at least one of the following beneficial technical effects:

1. by arranging the protective structure, firstly, supporting is carried out before excavation, the construction period of the supporting is shortened, and the purpose of shortening the whole construction period of the foundation pit is achieved;

2. by arranging the connecting angles and connecting the adjacent protective walls by using the connecting angles, the stability of the connection between the adjacent protective walls is improved;

3. through setting up stabilizing assembly, with the diapire fixed connection of protecting wall and protecting groove, then excavate on one side again, fix protecting wall and protecting groove's lateral wall with the reinforcement assembly on one side, promote the stability of protecting wall when as excavation supporting.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view aimed at showing the splicing of guard plates;

FIG. 3 is a schematic diagram intended to show the structure of the post-installation stabilizing assembly after excavation of a portion;

fig. 4 is a schematic view for illustrating the excavation of the foundation pit.

In the figure, 1, a guard; 11. a protective wall; 111. a protection plate; 12. a protective bath; 13. a connecting angle; 2. a connecting assembly; 21. connecting grooves; 22. connecting blocks; 3. a stabilizing assembly; 31. a stabilization well; 32. a stabilizer bar; 4. a reinforcement assembly; 41. a through hole; 42. a reinforcing bar; 43. an end plate; 5. a clamping assembly; 51. a clamping groove; 52. a clamping block; 6. and (6) foundation pit.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example one

Referring to fig. 1 and 2, the small foundation pit excavation protection structure disclosed by the invention comprises protection walls 11, protection grooves 12 and connecting angles 13, wherein the protection grooves 12 are vertically arranged at the edge of a foundation pit 6, the protection grooves 12 are arranged around the foundation pit 6, the protection walls 11 and the connecting angles 13 are prefabricated by reinforced concrete, the protection walls 11 are provided with a plurality of protection walls 11, each protection wall 11 is arranged in the protection groove 12, each side of the foundation pit 6 is provided with a protection wall 11, the connecting angles 13 are arranged between adjacent protection walls 11, and a connecting assembly 2 is arranged between each connecting angle 13 and the protection wall 11; every protective wall 11 all includes a plurality of protection plate 111, and every equal vertical setting of protection plate 111 is provided with joint subassembly 5 between the adjacent protection plate 111 in protection groove 12, all is provided with between the diapire of every protection plate 111 and protection groove 12 and stabilizes the subassembly 3, all is provided with between the lateral wall of every protection plate 111 and protection groove 12 and strengthens the subassembly 4. When using protective structure, protective slot 12 is seted up at the edge of foundation ditch 6 to the head seat, then place a plurality of blocks of protection plate 111 in protective slot 12 again, connect through joint subassembly 5 between the continuous protection plate 111, then place connection angle 13 between two adjacent protective wall 11, utilize coupling assembling 2 to be connected connection angle 13 and protective wall 11, reuse stabilizing component 3 is connected fixed with protective wall 11 and protective slot 12's diapire, then begin to carry out excavation of foundation ditch 6, excavation is carried out on one side of foundation ditch 6, on one side be connected fixedly with the lateral wall of protective plate 111 and protective slot 12 with strengthening component 4, until finishing excavating foundation ditch 6, reach the purpose that shortens foundation ditch 6's whole construction cycle.

Referring to fig. 1 and 2, joint subassembly 5 includes joint piece 52 and joint groove 51, and joint groove 51 is seted up at the lateral wall that guard plate 111 is close to adjacent guard plate 111, and joint groove 51 runs through the top of guard plate 111, and joint piece 52 keeps away from the lateral wall fixed connection in joint groove 51 with guard plate 111, and joint piece 52 is pour with guard plate 111 an organic whole and is formed, and during the lateral wall butt of adjacent guard plate 111, joint piece 52 is located joint groove 51, and joint piece 52 is pegged graft with joint groove 51 and is cooperated. When adjacent protection plate 111 connects, at first with protection plate 111 handling to protection tank 12 in, then with adjacent protection plate 111 handling to protection plate 111's top again, make joint piece 52 align with joint groove 51, then descend adjacent protection plate 111 to protection tank 12 in, make protection plate 111 drive joint piece 52 and peg graft in joint groove 51, continue the downward slip protection plate 111, protection plate 111 drives joint piece 52 and slides in joint groove 51.

Referring to fig. 1 and 2, coupling assembling 2 includes the connecting groove 21 of T type and the connecting block 22 of T type, connecting groove 21 sets up at the lateral wall that protecting wall 11 is close to connecting angle 13, the vertical setting of connecting groove 21, connecting groove 21 runs through the top of protecting wall 11, connecting block 22 is close to the lateral wall fixed connection of protecting wall 11 with connecting angle 13, connecting block 22 and connecting angle 13 integrative pouring form, connecting block 22 suits with connecting groove 21, connecting block 22 pegs graft the cooperation with connecting groove 21, connecting block 22 and connecting groove 21 sliding connection. When being connected the splice angle 13 with protecting wall 11, utilize machinery with splice angle 13 handling to protecting wall 11 junction, make connecting block 22 align with spread groove 21, then promote splice angle 13 and drive connecting block 22 and peg graft in spread groove 21, promote splice angle 13 and make splice angle 13 drive connecting block 22 and slide in spread groove 21, when splice angle 13 is located protecting groove 12 completely, connecting block 22 slides in spread groove 21 completely.

Referring to fig. 2, the stabilizing assembly 3 includes a stabilizing hole 31 and a stabilizing rod 32, the stabilizing hole 31 is opened at the top end of each protection plate 111, the stabilizing hole 31 penetrates through the protection plate 111, the stabilizing rod 32 is in plugging fit with the stabilizing hole 31, the stabilizing rod 32 is vertically arranged, the bottom end of the stabilizing rod 32 is arranged to be pointed, and the bottom end of the stabilizing rod 32 penetrates through the stabilizing hole 31 and is inserted into the bottom wall of the protection groove 12. When the stabilizing assembly 3 is used, the tip of the stabilizing rod 32 is inserted into the stabilizing hole 31, the stabilizing rod 32 is pushed to slide in the stabilizing hole 31, the tip of the stabilizing rod 32 is abutted against the bottom wall of the protective groove 12, then the top end of the stabilizing rod 32 is hammered, and the tip of the stabilizing rod 32 is inserted into the bottom wall of the protective groove 12.

Referring to fig. 3 and 4, reinforcement assembly 4 includes through-hole 41, stiffener 42 and end plate 43, a plurality of through-hole 41 is all seted up to the lateral wall of each guard plate 111, a plurality of through-hole 41 is two vertical rows of arranging, guard plate 111 is all run through to every through-hole 41, stiffener 42 is provided with a plurality of, every stiffener 42 all inclines to set up, end plate 43 of the equal fixed connection of one end of every stiffener 42, the one end that end plate 43 was kept away from to every stiffener 42 is passed in a through-hole 41 and is inserted the lateral wall of protecting groove 12, a stiffener 42 of all pegging graft of every through-hole 41, all end plates 43 all with the lateral wall butt of protecting wall 11, all be provided with a plurality of arch that increases frictional force on every stiffener 42, every arch all with stiffener 42 fixed connection. When using reinforcement assembly 4, at first carry out excavation of foundation ditch 6, when excavation of foundation ditch 6 reaches first through-hole 41 in the through-hole 41 of a plurality of vertical range, then keep away from the one end of end plate 43 with stiffener 42 and insert in through-hole 41, then promote in end plate 43 drives stiffener 42 and inserts the lateral wall of protective housing 12, make end plate 43 and guard plate 111 butt.

The implementation principle of the embodiment is as follows: when the protective structure is installed, firstly, the edge of the foundation pit 6 is measured on the ground, then the protective groove 12 is dug around the edge of the foundation pit 6, the bottom wall of the protective groove 12 is dug to be at the same height with the bottom wall of the foundation pit 6, then, the protection plates 111 are lifted into the protection groove 12 by a machine, when the adjacent protection plates 111 are spliced with each other, the protection plate 111 is lifted to be placed on the top end of the protection tank 12, the clamping blocks 52 of the lifted protection plate 111 are aligned with the clamping grooves 51 of the protection plate 111 placed in the protection tank 12, then the lifted protection plate 111 is lowered into the protection groove 12, the clamping block 52 is inserted into the clamping groove 51, the protection plate 111 drives the clamping block 52 to slide in the clamping groove 51 of the adjacent protection plate 111, when the protection plates 111 are completely positioned in the protection groove 12, the clamping blocks 52 are completely positioned in the clamping grooves 51, and a plurality of protection plates 111 are sequentially lifted into the protection groove 12 to form a protection wall 11; when the adjacent protection walls 11 are connected, the connecting angle 13 is lifted to the position between the adjacent protection walls 11, so that the connecting block 22 is aligned with the connecting groove 21, then the connecting angle 13 slides downwards into the protection groove 12, so that the connecting block 22 is inserted into the connecting groove 21, the connecting angle 13 continues to slide downwards, the connecting angle 13 drives the connecting block 22 to slide in the connecting groove 21, and when the connecting angle 13 is completely positioned in the protection groove 12, the connecting block 22 is completely positioned in the connecting groove 21; then, inserting the tip of the stabilizer bar 32 into the stabilizing hole 31 of the protection plate 111, pushing the stabilizer bar 32 while the stabilizer bar 32 slides in the stabilizing hole 31, hammering the stabilizer bar 32 to insert the tip of the stabilizer bar 32 into the bottom wall of the protection groove 12 when the tip of the stabilizer bar 32 abuts against the bottom wall of the protection groove 12, and sequentially inserting the stabilizer bar 32 into each stabilizing hole 31; then, excavation of the foundation pit 6 is started, when the foundation pit 6 is excavated and leaks out of the through holes 41 in the protection plates 111 to a certain degree, one end of the reinforcing rod 42 far away from the end plate 43 penetrates through the through holes 41 to be inserted into the side wall of the protection groove 12, the end plate 43 is pushed to enable the end plate 43 to drive the reinforcing rod 42 to be continuously inserted into the side wall of the protection groove 12, finally, the end plate 43 is abutted to the side wall of the protection plate 111, after the reinforcing rod 42 is inserted into each protection plate 111, excavation is carried out again, when excavation is carried out to another through hole 41, the reinforcing rod 42 is inserted into another through hole 41, and the rest is done in a similar manner until the bottom wall of the foundation pit 6 is excavated.

Example two

s1, excavating the protective groove 12: firstly, measuring the position of the foundation pit 6, paying off the periphery of the foundation pit 6 on the ground after the measurement is finished, then excavating the protective groove 12 by using excavating equipment according to the line of the edge of the foundation pit 6, excavating the protective groove 12 to the depth required by the foundation pit 6, and cleaning the bottom wall of the protective groove 12.

S2, placing the protective wall 11: with prefabricated protection plate 111 handling to in the protective tank 12, be connected through the grafting cooperation of joint piece 52 with joint groove 51 between the adjacent protection plate 111, then utilize the grafting cooperation of connecting block 22 and connecting groove 21 to be connected the angle of connection 13 and protection plate 111 fixedly, follow protection tank 12 installation protection plate 111 in proper order, make protection plate 111 fill protection tank 12.

S3, placing stabilizer bar 32: one end of stabilizer bar 32 with the tip is pegged graft in stabilizer hole 31, promotes stabilizer bar 32 and makes stabilizer bar 32 slide in stabilizer hole 31, and when the most advanced of stabilizer bar 32 and the diapire butt of protective groove 12, the most advanced one end is kept away from to hammering stabilizer bar 32, makes the most advanced of stabilizer bar 32 insert in the diapire of protective groove 12, utilizes stabilizer bar 32 to the limiting displacement of stabilizer hole 31, makes guard plate 111 and protective groove 12 keep fixed.

S4, excavating a foundation pit 6: excavating the foundation pit 6 by using an excavating machine, excavating the side wall of the protective groove 12 close to the foundation pit 6 to enable the protective groove 12 to be communicated with the foundation pit 6, inserting one end, far away from the end plate 43, of the reinforcing rod 42 into the through hole 41 when the first through hole 41 is excavated, hammering the end plate 43 to enable one end, far away from the end plate 43, of the reinforcing rod 42 to be inserted into the side wall of the protective groove 12, and enabling the end plate 43 to be abutted against the protective plate 111; all the end plates 43 are reinforced in the existing excavation stage, then excavated downwards, and then the protective plates 111 are reinforced by the reinforcing rods 42 when another through hole 41 is excavated, and so on until the excavation of the foundation pit 6 is finished.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. The utility model provides a little foundation ditch excavation protective structure which characterized in that: protective structure includes protecting wall (11), protecting wall (11) are provided with a plurality of, a plurality of protecting wall (11) ring foundation ditch (6) set up, each side of foundation ditch (6) all sets up protecting wall (11), every protecting wall (11) are prefabricated protecting wall (11), adjacent protecting wall (11) junction is provided with tie-angle (13), be provided with coupling assembling (2) between tie-angle (13) and protecting wall (11), subaerial guard groove (12) of having seted up, protecting groove (12) ring foundation ditch (6) set up, a plurality of protecting wall (11) all set up in foundation ditch (6), be provided with stabilizing component (3) between the diapire of protecting wall (11) and guard groove (12), be provided with between the lateral wall of protecting wall (11) and guard groove (12) reinforcing component (4).

2. The excavation protection structure of a small foundation pit according to claim 1, characterized in that: coupling assembling (2) are including spread groove (21) and connecting block (22), and the lateral wall in protecting wall (11) is seted up in spread groove (21), and spread groove (21) run through the top of protecting wall (11), connecting block (22) and connection angle (13) fixed connection, and connecting block (22) are pegged graft the cooperation with spread groove (21), connecting block (22) and spread groove (21) sliding connection.

3. The excavation protection structure of a small foundation pit as claimed in claim 2, wherein: the connecting groove (21) is arranged to be a T-shaped connecting groove (21), the connecting block (22) is arranged to be a T-shaped connecting block (22), and the connecting block (22) is adapted to the connecting groove (21).

4. The excavation protection structure of a small foundation pit according to claim 1, characterized in that: the stabilizing assembly (3) comprises a stabilizing hole (31) and a stabilizing rod (32), the stabilizing hole (31) is arranged at the top end of the protective wall (11), the stabilizing hole (31) penetrates through the protective wall (11), the stabilizing rod (32) is in plug-in fit with the stabilizing hole (31), and one end of the stabilizing rod (32) penetrates through the stabilizing hole (31) and is inserted into the bottom wall of the protective groove (12).

5. The excavation protection structure of a small foundation pit according to claim 4, characterized in that: one end of the stabilizing rod (32) inserted into the bottom wall of the protective groove (12) is arranged to be a tip.

6. The excavation protection structure of a small foundation pit according to claim 1, characterized in that: strengthen subassembly (4) including through-hole (41), stiffener (42) and end plate (43), the lateral wall in protecting wall (11) is seted up in through-hole (41), and through-hole (41) are provided with a plurality of, and every through-hole (41) all run through protecting wall (11), the one end and end plate (43) fixed connection of stiffener (42), and the other end passes through in through-hole (41) inserts the lateral wall of protecting groove (12), end plate (43) and the lateral wall butt of protecting wall (11).

7. The excavation protection structure of a small foundation pit according to claim 1, characterized in that: every protective wall (11) all includes a plurality of blocks of protection plate (111), and every protection plate (111) all sets up stabilizing component (3) with the diapire of protective housing (12), and the lateral wall of every protection plate (111) and protective housing (12) all sets up reinforcement unit (4), is provided with joint subassembly (5) between adjacent protection plate (111).

8. The excavation protection structure of a small foundation pit according to claim 7, wherein: joint subassembly (5) are including joint piece (52) and joint groove (51), and one side at protection plate (111) is seted up in joint groove (51), and one side fixed connection in joint groove (51) is kept away from with protection plate (111) in joint piece (52), and when adjacent protection plate (111) is connected, joint piece (52) and joint groove (51) cooperation of pegging graft.

9. A construction method for excavating a protective structure in a small foundation pit is characterized by comprising the following steps:

s1, excavating a protective groove (12): firstly, measuring the position of a foundation pit (6), then, using excavating equipment to open a protective groove (12) according to the edge of the foundation pit (6), and cleaning the bottom wall of the protective groove (12);

s2, placing a protective wall (11): hoisting prefabricated protection plates (111) into the protection groove (12), connecting adjacent protection plates (111) through the insertion fit of the clamping blocks (52) and the clamping grooves (51), then connecting and fixing the connecting corners (13) and the protection plates (111) by the insertion fit of the connecting blocks (22) and the connecting grooves (21), and sequentially installing the protection plates (111) along the protection groove (12) to fully fill the protection groove (12) with the protection plates (111);

s3, placing stabilizer bar (32): inserting one end of the stabilizer bar (32) with a tip end into the stabilizing hole (31), pushing the stabilizer bar (32) to enable the stabilizer bar (32) to slide in the stabilizing hole (31), hammering one end of the stabilizer bar (32) far away from the tip end when the tip end of the stabilizer bar (32) is abutted to the bottom wall of the protective groove (12), enabling the tip end of the stabilizer bar (32) to be inserted into the bottom wall of the protective groove (12), and enabling the protective plate (111) and the protective groove (12) to be fixed by utilizing the limiting effect of the stabilizer bar (32) on the stabilizing hole (31);

s4, excavating the foundation pit (6): excavating the foundation pit (6) by using an excavating machine, excavating the side wall of the protective groove (12) close to the foundation pit (6) to communicate the protective groove (12) with the foundation pit (6), inserting one end of the reinforcing rod (42) far away from the end plate (43) into the through hole (41) when excavating to the first through hole (41), hammering the end plate (43) to insert one end of the reinforcing rod (42) far away from the end plate (43) into the side wall of the protective groove (12), and abutting the end plate (43) with the protective plate (111); all the end plates (43) are reinforced in the existing excavation stage, then are excavated downwards, and then the protective plates (111) are reinforced by using the reinforcing rods (42) when another through hole (41) is excavated, and so on until the excavation of the foundation pit (6) is finished.