阅读说明：本技术 一种预制现浇相结合的地下连续墙施工方法 (Construction method of prefabricated cast-in-place combined underground diaphragm wall ) 是由 翁奔哲 朱连根 陈跃 童晓军 张金勇 沈金海 于 2019-10-25 设计创作，主要内容包括：本发明公开了一种预制现浇相结合的地下连续墙施工方法。它按不同间距交替间隔划分先行幅槽段和闭合幅槽段,先施工先行幅槽段,再施工闭合幅槽段,得到连续墙,用于建筑基坑施工时的挡土和止水等用。本发明通过采用上述施工方法,能解决地下连续墙“绕流”、接缝夹泥、锁口管无法下放以及上拔不畅的问题,缩短了单元槽段的施工时间,减少了减少大量人工机械同时作业的时间,由于先行幅采用预制,减少了背侧安放反力箱的工序,提高了效率,为地下连续墙施工提供了一种全新的方法,本发明的地下连续墙的施工方法成本更省、工期更短,且外观质量及常规施工的质量通病得到了很好的控制,易于推广应用。(The invention discloses a construction method of a prefabricated cast-in-place combined underground diaphragm wall. The diaphragm wall is used for retaining soil, stopping water and the like during construction of a building foundation pit. By adopting the construction method, the problems of 'flow winding', seam mud clamping and incapability of lowering and pulling up the fore shaft pipe of the underground continuous wall are solved, the construction time of the unit groove section is shortened, the time for simultaneously operating a large number of manual machines is reduced, the process of placing the reaction box on the back side is reduced due to the adoption of prefabrication in advance, the efficiency is improved, and a brand new method is provided for the construction of the underground continuous wall.)

1. A prefabricated cast-in-place combined underground diaphragm wall construction method is characterized in that a guide wall is constructed on the ground along the side line of an underground structure or a high-rise building foundation pit designed on a drawing firstly, a leading-width groove section and a closed-width groove section are alternately divided at intervals according to different intervals after the construction of the guide wall is finished, the leading-width groove section is firstly excavated in the guide wall by a grooving machine under the state of slurry wall protection, a prefabricated wall body prefabricated in advance is placed in the excavated leading-width groove section, then concrete pouring is carried out on a cavity in the middle of the prefabricated wall body, and all the leading-width groove sections are constructed in sequence by repeating the steps; and excavating the closed width groove section to the designed depth by using a trenching machine under the state of slurry wall protection, then placing a reinforcement cage in the excavated closed width groove section filled with slurry and pouring concrete, gradually pouring the concrete upwards from the bottom of the groove section trench, replacing the slurry, forming a reinforced concrete wall under the underground of the closed width groove section, and repeating the steps to construct all the closed width groove sections to form an integral underground continuous wall.

2. The construction method of the prefabricated cast-in-place combined underground continuous wall as claimed in claim 1, which is characterized in that the concrete construction method comprises the following steps:

1) selecting a grooving machine with the same width and size as the standard underground continuous wall designed by the drawing, and prefabricating a prefabricated wall body with the width matched with the design width of the drawing;

2) excavating guide wall ditches, respectively pouring inverted L-shaped guide walls on two sides of each guide wall ditch, enabling the distance between the two inverted L-shaped guide walls to be the same as the width of a standard underground continuous wall designed by a drawing, connecting each guide wall ditch into a closed guide wall along the side line of a foundation pit, and enabling the depth of each inverted L-shaped guide wall to be equal to the depth of each guide wall ditch;

3) after the inverted L-shaped guide wall is shaped, alternately dividing the first width groove section and the closed width groove section at intervals according to different intervals; excavating the advanced groove section to a designed depth by using the grooving machine in the step 1) under the states of the inverted L-shaped guide wall and the slurry retaining wall to obtain an advanced construction groove section of the underground diaphragm wall;

4) placing a prefabricated wall body with prefabricated bottom sections into the fore-width groove sections excavated in the step 3), fixing the top ends of the prefabricated wall bodies with the bottom sections on the guide wall, butting the adjacent middle prefabricated wall bodies, sequentially lowering, finally butting the prefabricated wall bodies with the top sections, lowering the prefabricated wall bodies to the designed depth, pouring concrete into the square through long holes (2) of the prefabricated wall bodies, plugging the square through long holes (2), and completing construction of the fore-width groove sections;

5) excavating to a designed depth by using the trenching machine in the step 1) under the states of the inverted L-shaped guide wall and the slurry retaining wall to obtain a closed construction groove section of the underground continuous wall;

6) placing a prefabricated reinforcement cage into the closed construction groove section, and then pouring concrete into the groove section in which the reinforcement cage is placed by using a guide pipe method to form a reinforced concrete wall section;

7) and (5) repeating the step 5) and the step 6) until all the construction of the closed width groove section is completed, and obtaining the underground continuous wall required by the design of the drawing.

3. The construction method of the prefabricated cast-in-place combined underground continuous wall according to claim 2, characterized in that the prefabricated wall in the step 1) is a pretensioned prestressed wall, the prefabricated wall comprises a hollow square main body (1), 1-2 square through long holes (2) are arranged in the square main body (1) in the axial direction, trapezoidal grooves (3) are symmetrically formed in the side surface of the square main body (1) in the axial direction, one end of the upper end head and the lower end head of the middle prefabricated wall is provided with a connecting protrusion (4), the other end of the upper end head and the lower end head of the middle prefabricated wall is provided with a connecting groove (5) matched with the connecting protrusion (4), the lower end of the top prefabricated wall and the upper end of the bottom prefabricated wall are provided with connecting protrusions (4) or connecting grooves (5) matched and connected with the connecting grooves (5) or connecting protrusions (4) of the adjacent sections, and the length of, preferably 12-15m, with a width of 2m, which is 2-4cm smaller than the design width.

4. The construction method of the prefabricated cast-in-place combined underground continuous wall as claimed in claim 3, wherein the bottom of the prefabricated wall body of the bottom section is provided with a pointed head part (7); the top of the top section prefabricated wall body is provided with two vibration steel plates (23), the two vibration steel plates (23) can be matched with and clamped by a clamping plate of a vibration hammer, in the process of lowering the prefabricated wall body in the step 4), the vibration hammer clamps the two vibration steel plates (23), power is provided for lowering the prefabricated wall body through vibration, and smooth lowering is guaranteed; four corners of the top of each section of prefabricated wall body and one side surface are respectively provided with 4 lifting lugs (24), and four corners of the bottom of each section of prefabricated wall body are correspondingly provided with 4 grooves matched with the lifting lugs (24).

5. The construction method of the prefabricated cast-in-place combined underground diaphragm wall as claimed in claim 3, characterized in that a convex connecting steel plate (8) is welded on the outer side of a convex main rib (10) at the width position of the connecting protrusion (4), a groove connecting steel plate (9) is welded on the outer side of a groove main rib (12) at the width position of the connecting groove (5), bolt holes are correspondingly arranged on the convex connecting steel plate (8) and the groove connecting steel plate (9), nuts (25) are arranged on the inner sides of the bolt holes of the groove connecting steel plate (9), in two adjacent butted prefabricated wall bodies, the connecting protrusion (4) of one prefabricated wall body is connected with the connecting groove (5) of the other prefabricated wall body, and is sequentially connected with the bolt holes of the convex connecting steel plate (8) and the groove connecting steel plate (9) from outside to inside through bolts (11), then is connected and fixed with the nuts (25), a protective layer (26) is coated on the outer, two ends of the protective layer (26) extend to the connecting end surfaces of two adjacent sections of prefabricated wall bodies.

6. The construction method of the prefabricated cast-in-place combined underground diaphragm wall as claimed in claim 3, characterized in that mounting and fixing holes (6) are symmetrically formed in both sides of the upper end of the square main body (1), the mounting and fixing holes (6) are arranged to penetrate through the trapezoidal grooves (3) and are used for mounting connecting rods to fix the prefabricated wall body during hoisting.

7. The construction method of the prefabricated cast-in-place combined underground diaphragm wall as claimed in claim 2, wherein the excavation depth of the guide wall trench in the step 2) is 1.5-2.5m, and the length of each segment is 15-20 m; the top of the inverted L-shaped guide wall extends to the ground for 0.8-1.2 m; when the inverted L-shaped guide wall is constructed, a deformed steel bar single-layer net piece with the diameter of 12mm is added into an inverted L-shaped steel plate, and the longitudinal and transverse spacing of the deformed steel bar single-layer net piece is 200mm multiplied by 200 mm.

8. The construction method of a prefabricated cast-in-place combined underground diaphragm wall as claimed in claim 2, wherein the width of the leading width groove section in the step 3) is 2m, and the width of the closed width groove section is 6 m.

9. The construction method of the prefabricated cast-in-place combined underground continuous wall according to claim 2, characterized in that when the prefabricated wall is lowered in the step 4), the inverted-L-shaped guide wall is correspondingly provided with jacking positioning frames for fixing the prefabricated wall when in butt joint and ensuring the prefabricated wall to be vertically lowered, each jacking positioning frame comprises a base (14) for placing the jacking positioning frame on the inverted-L-shaped guide wall, 4 jacking oil cylinders (13) and two horizontal adjusting oil cylinders (18) are arranged on the base (14), a supporting platform is arranged on the 4 jacking oil cylinders (13), the supporting platform comprises jacking stress frames (15) arranged on the jacking oil cylinders (13) and horizontal positioning frames (17) positioned on two sides of the jacking stress frames (15), and the distance between the two horizontal positioning frames (17) is larger than the width of the prefabricated wall; horizontal adjustment hydro-cylinder (18) inboard is connected with pulley mounting panel (28), and the inboard of pulley mounting panel (28) vertically is equipped with two sets of pulleys (29), during prefabricated wall body installation, adjust the distance between two pulley mounting panels (28) by horizontal adjustment hydro-cylinder (18) earlier, make pulley (29) interval and the width matching of prefabricated wall body of both sides, pass corresponding installation fixed orifices (6) with the connecting rod again, the jacking atress frame (15) position on 4 jacking hydro-cylinder (13) upper portions is placed in the both ends of connecting rod, be equipped with reinforcing floor (16) on jacking atress frame (15), be connected with last section prefabricated wall body after will prefabricating the wall body fixed, pulley (29) can guarantee that prefabricated wall body is vertical when fixing a position prefabricated wall body and transfer.

10. The construction method of the prefabricated cast-in-place combined underground continuous wall according to claim 2, characterized in that after the excavation of the closed construction groove section of the continuous wall in the step 5) is finished and before concrete is poured, the surfaces of the trapezoidal grooves (3) on the two sides of the prefabricated wall are cleaned by a wall brushing device to remove sludge on the surfaces, the wall brushing device comprises a brush holder (21) formed by fixedly connecting two mounting plates, a hanging plate (19) is fixedly arranged at the upper middle part of the brush holder (21), at least two hanging holes (1901) are respectively formed at the two ends of the hanging plate (19) and connected with a crane through the hanging holes (1901), at least two groups of reinforcing steel plates (20) are obliquely arranged in a cavity in the brush holder (21), a steel brush clamping plate (22) is arranged on at least one side of the brush holder (21), the structure of the steel brush clamping plate (22) is matched with the trapezoidal grooves (3), steel wires are arranged on the steel brush clamping plate (22), as a steel brush, is used for brushing off the mud skin on the trapezoidal groove (3).

Technical Field

The invention belongs to the technical field of building construction, and particularly relates to a construction method suitable for underground continuous walls except rocks.

Background

At present, the construction of underground diaphragm walls is carried out by adopting a hydraulic grab bucket to carry out grooving construction, then a steel reinforcement cage is put down, a fore shaft pipe or a joint box is placed, and finally concrete is poured. The traditional construction method needs a large amount of manpower and machines for simultaneous construction, concrete is easy to flow around in some silt stratums, joints cannot be processed cleanly, and finally seam water leakage is caused. The method adopts the prefabricated wall section to replace the traditional fore shaft pipe and the joint box, avoids the concrete 'streaming problem', ensures the water stopping effect of the joint, controls a great amount of time for simultaneously using manpower and machinery, and also responds to the idea of developing the assembly type green building in China.

Disclosure of Invention

In view of the above problems in the prior art, an object of the present invention is to provide a method for constructing an underground diaphragm wall, which effectively controls common quality problems.

The construction method of the prefabricated cast-in-place combined underground diaphragm wall is characterized in that a guide wall is constructed on the ground along the side line of an underground structure or a high-rise building foundation pit designed on a drawing firstly, a fore-frame groove section and a closed-frame groove section are alternately divided at intervals according to different intervals after the construction of the guide wall is finished, the fore-frame groove section is firstly excavated in the guide wall by a grooving machine under the state of slurry wall protection, a prefabricated wall body prefabricated in advance is placed into the excavated fore-frame groove section, then concrete pouring is carried out on a cavity in the middle of the prefabricated wall body, and all the fore-frame groove sections are constructed in sequence by repeating the steps; and excavating the closed width groove section to the designed depth by using a trenching machine under the state of slurry wall protection, then placing a reinforcement cage in the excavated closed width groove section filled with slurry and pouring concrete, gradually pouring the concrete upwards from the bottom of the groove section trench, replacing the slurry, forming a reinforced concrete wall under the underground of the closed width groove section, and repeating the steps to construct all the closed width groove sections to form an integral underground continuous wall.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized by comprising the following specific construction methods:

1) selecting a grooving machine with the same width and size as the standard underground continuous wall designed by the drawing, and prefabricating a prefabricated wall body with the width matched with the design width of the drawing;

2) excavating guide wall ditches, respectively pouring inverted L-shaped guide walls on two sides of each guide wall ditch, enabling the distance between the two inverted L-shaped guide walls to be the same as the width of a standard underground continuous wall designed by a drawing, connecting each guide wall ditch into a closed guide wall along the side line of a foundation pit, and enabling the depth of each inverted L-shaped guide wall to be equal to the depth of each guide wall ditch;

3) after the inverted L-shaped guide wall is shaped, alternately dividing the first width groove section and the closed width groove section at intervals according to different intervals; excavating the advanced groove section to a designed depth by using the grooving machine in the step 1) under the states of the inverted L-shaped guide wall and the slurry retaining wall to obtain an advanced construction groove section of the underground diaphragm wall;

4) placing a prefabricated wall body with prefabricated bottom sections into the fore-width groove sections excavated in the step 3), fixing the top ends of the prefabricated wall bodies with the bottom sections on the guide walls, butting the adjacent middle prefabricated wall bodies, sequentially lowering, finally butting the prefabricated wall bodies with the top sections, lowering the prefabricated wall bodies to the designed depth, pouring concrete into the square through long holes of the prefabricated wall bodies, plugging the square through long holes, and completing construction of the fore-width groove sections;

5) excavating to a designed depth by using the trenching machine in the step 1) under the states of the inverted L-shaped guide wall and the slurry retaining wall to obtain a closed construction groove section of the underground continuous wall;

6) placing a prefabricated reinforcement cage into the closed construction groove section, and then pouring concrete into the groove section in which the reinforcement cage is placed by using a guide pipe method to form a reinforced concrete wall section;

7) and (5) repeating the step 5) and the step 6) until all the construction of the closed width groove section is completed, and obtaining the underground continuous wall required by the design of the drawing.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that the prefabricated wall in the step 1) is a pretensioned prestressed wall, the prefabricated wall comprises a hollow square main body, 1-2 square through long holes are formed in the square main body in the axial direction, trapezoidal grooves are symmetrically formed in the side face of the square main body in the axial direction, connecting protrusions are arranged at one end of the upper end head and one end of the lower end head of the middle prefabricated wall, connecting grooves matched with the connecting protrusions are formed in the other end of the upper end head and the lower end head of the middle prefabricated wall, connecting protrusions or connecting grooves are formed in the lower end of the top prefabricated wall and the upper end of the bottom prefabricated wall and are connected with the connecting grooves or connecting protrusions of the adjacent prefabricated wall in a matching mode, the length of the prefabricated wall is 10-16m, preferably 12-15m, the width of the prefabricated wall.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that the bottom of the prefabricated wall body of the bottom section is provided with a pointed head part; the top of the top section prefabricated wall body is provided with two vibration steel plates which can be matched and clamped with the clamping plates of the vibration hammer, in the step 4), the vibration hammer clamps the two vibration steel plates in the process of lowering the prefabricated wall body, power is provided for lowering the prefabricated wall body through vibration, and smooth lowering is guaranteed; every section of prefabricated wall body top four corners and a side are equipped with 4 lugs respectively, and every section of prefabricated wall body bottom four corners corresponds the setting and is equipped with 4 recesses that match with the lug.

The construction method of the prefabricated cast-in-place combined underground diaphragm wall is characterized in that a convex connecting steel plate is welded on the outer side of a convex main rib at the width position of a connecting convex, a groove connecting steel plate is welded on the outer side of a groove main rib at the width position of a connecting groove, bolt holes are correspondingly formed in the convex connecting steel plate and the groove connecting steel plate, nuts are arranged on the inner sides of the bolt holes of the groove connecting steel plate, a connecting convex of one prefabricated wall body is connected with a connecting groove of the other prefabricated wall body in adjacent butt joint, bolts sequentially pass through the bolt holes of the convex connecting steel plate and the groove connecting steel plate from outside to inside and then are fixedly connected with the nuts, a protective layer is coated on the outer surface of the convex connecting steel plate, and two ends of the protective layer extend to the.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that mounting and fixing holes are symmetrically formed in two sides of the upper end portion of the square main body and penetrate through the trapezoidal grooves, and the mounting and fixing holes are used for mounting connecting rods to fix the prefabricated wall during hoisting.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that the excavation depth of the guide wall trench in the step 2) is 1.5-2.5m, and the length of each section is 15-20 m; the top of the inverted L-shaped guide wall extends to the ground for 0.8-1.2 m; when the inverted L-shaped guide wall is constructed, a deformed steel bar single-layer net piece with the diameter of 12mm is added into an inverted L-shaped steel plate, and the longitudinal and transverse spacing of the deformed steel bar single-layer net piece is 200mm multiplied by 200 mm.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that the width of the front width groove section in the step 3) is 2m, and the width of the closed width groove section is 6 m.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that when the prefabricated wall is lowered in the step 4), jacking positioning frames are correspondingly arranged on the inverted L-shaped guide wall and used for fixing the prefabricated wall during butt joint and ensuring that the prefabricated wall is vertically lowered, each jacking positioning frame comprises a base for placing the jacking positioning frame on the inverted L-shaped guide wall, 4 jacking oil cylinders and two horizontal adjusting oil cylinders are arranged on the base, supporting platforms are arranged on the 4 jacking oil cylinders and comprise jacking stress frames arranged on the jacking oil cylinders and horizontal positioning frames positioned on two sides of the jacking stress frames, and the distance between the two horizontal positioning frames is larger than the width of the prefabricated wall; horizontal adjustment hydro-cylinder inboard is connected with the pulley mounting panel, and the inboard of pulley mounting panel vertically is equipped with two sets of pulleys, during the installation of prefabricated wall body, earlier by the distance between two pulley mounting panels of horizontal adjustment hydro-cylinder regulation, make the pulley interval of both sides and the width matching of prefabricated wall body, pass the installation fixed orifices that corresponds with the connecting rod again, the jacking atress frame position on 4 jacking hydro-cylinders upper portion is arranged in at the both ends of connecting rod, is equipped with the reinforced rib board on the jacking atress frame, with the fixed back of prefabricated wall body and last a section of prefabricated wall body coupling, the pulley can guarantee that prefabricated wall body is vertical transfers when the prefabricated wall body in.

The construction method of the prefabricated cast-in-place combined underground continuous wall is characterized in that after the excavation of the continuous wall closed construction groove section in the step 5) is finished and before concrete is poured, a wall brushing device is adopted to clean the surfaces of the trapezoidal grooves on the two sides of the prefabricated wall body and remove sludge on the surfaces of the trapezoidal grooves, the wall brushing device comprises a brush holder formed by fixedly connecting two mounting plates, a hanging plate is fixedly arranged at the upper middle part of the brush holder, at least two hanging holes are respectively formed in the two ends of the hanging plate and are connected with a crane through the hanging holes, at least two groups of reinforcing steel plates are obliquely arranged in a cavity in the brush holder, at least one side of the brush holder is provided with a steel brush clamping plate, the structure of the steel brush clamping plate is matched with the trapezoidal grooves, and steel wires serving as steel brushes are arranged on the steel brush clamping plate and used for.

By adopting the technology, compared with the prior art, the invention has the following beneficial effects:

1) according to the characteristics of geological conditions, the construction method combining prefabrication and cast-in-place is adopted, so that the problems of 'flow bypassing' and difficult lowering and jacking of the fore shaft pipe reaction box in the conventional underground continuous wall construction are effectively solved, the construction quality of the underground continuous wall is improved, and the risk of later foundation pit excavation is reduced;

2) when the inverted L-shaped guide wall is constructed, the deformed steel bar single-layer net piece with the diameter of 12mm is added behind the L-shaped steel plate, the longitudinal and transverse spacing is limited to 200mm x 200mm, and the bearing capacity of the inverted L-shaped guide wall is improved;

3) when the prefabricated wall is constructed in advance, the length of the prefabricated wall is limited to 2000mm, and the width of the prefabricated wall is slightly smaller than the design width of the continuous wall (reduced by 2-4cm according to different geological conditions), so that the prefabricated wall can be conveniently and smoothly placed;

4) in order to meet the requirements of the horizontal and vertical properties of the front breadth, the jacking positioning frame is arranged before the prefabricated wall section is placed under the front breadth, the distance between the pulleys for assisting the prefabricated wall to slide downwards is adjusted through the horizontal adjusting oil cylinder, so that the distance is matched with the width of the prefabricated wall, and under the combined action of the pulleys and the horizontal positioning frame, the prefabricated wall can be effectively prevented from inclining in the process of placing the prefabricated wall, and certain power can be provided for the sliding downwards while the vertical property is ensured; the jacking cylinders are used for fixing the prefabricated wall body to perform upper and lower end connection operation, on the other hand, the prefabricated wall body can be conveniently lifted, and correction is performed by adjusting one or two jacking cylinders; according to the invention, the wall brushing device with a limited structure is adopted, so that mud on the side surface of the prefabricated wall body can be removed, and the bonding between the concrete cast in situ in the rear closed groove section and the prefabricated wall surface is more firm;

5) according to the construction method combining prefabrication and cast-in-place, the continuous wall is obtained through the construction method combining prefabrication and cast-in-place, the guide wall ditch excavation, the guide wall manufacturing, the prefabricated section construction in the previous frame, the closed and cast-in-place construction and the repeated operation in sequence, the problem of 'streaming' and the problem of joint construction are effectively solved, the total construction period is shorter, the time for simultaneously constructing a large number of manual machines is shortened greatly, and therefore the construction method combining prefabrication and cast-in-place has the advantages of being green, good in quality and controllable in risk, and is easy to popularize and apply.

Drawings

FIG. 1 is a schematic structural view of a prefabricated wall body with bottom sections according to the present invention;

FIG. 2 is a schematic structural view of a middle prefabricated wall according to the present invention;

FIG. 3 is a schematic view of the top section prefabricated wall structure of the present invention

FIG. 4 is a schematic view of a connection structure of two adjacent prefabricated walls;

FIG. 5 is a schematic view of a partially enlarged structure of two adjacent prefabricated walls when connected;

FIG. 6 is a schematic structural view of a jacking spacer of the present invention;

fig. 7 is a schematic structural view of the wall brushing device of the invention.

In the figure: 1-square main body, 2-square through long hole, 3-trapezoidal groove, 4-connecting bulge, 5-connecting groove, 6-mounting fixing hole, 7-pointed head, 8-bulge connecting steel plate, 9-groove connecting steel plate, 10-bulge main rib, 11-bolt, 12-groove main rib, 13-jacking oil cylinder, 14-base, 15-jacking stress frame, 16-reinforcing rib plate, 17-horizontal positioning frame, 18-horizontal adjusting oil cylinder, 19-hanger plate, 1901-hanger hole, 20-reinforcing steel plate, 21-brush holder, 22-steel brush clamp plate, 23-vibration steel plate, 24-hanger lug, 25-nut, 26-protective layer, 27-reserved steel bar, 28-pulley mounting plate, 29-pulley.

Detailed Description

The invention is further described below, but the scope of protection of the invention is not limited thereto:

firstly, the structures of prefabricated raw materials and auxiliary devices used in the construction of the prefabricated cast-in-place combined underground continuous wall related to the embodiment of the invention are explained, wherein the prefabricated wall comprises a bottom prefabricated wall body, a middle prefabricated wall body and a top prefabricated wall body; auxiliary device includes jacking locating rack and brush wall ware, specifically is:

as shown in FIGS. 1 to 3, the prefabricated walls of the present invention are pre-tensioned pre-stressed walls, the length of the prefabricated walls is 10 to 16m, preferably 12 to 15m, the width is 2m, and the width is 2 to 4cm smaller than the designed width. The prefabricated wall body comprises a hollow square main body 1, 1-2 square through long holes 2 are formed in the square main body 1 in the axial direction, trapezoidal grooves 3 are symmetrically formed in the side face of the square main body 1 in the axial direction, a connecting bulge 4 is arranged at one end of each of the upper end head and the lower end head of each prefabricated wall body, a connecting groove 5 matched with the connecting bulge 4 is formed in the other end of each prefabricated wall body, mounting and fixing holes 6 are symmetrically formed in two sides of the upper end portion of the square main body 1, the mounting and fixing holes 6 penetrate through two sides of the trapezoidal grooves 3, and the mounting and fixing holes are used for mounting connecting;

in the embodiment of the invention, each section of prefabricated wall body is provided with two square through long holes 2, as shown in figure 1, the top of the bottom section of prefabricated wall body in the embodiment of the invention is provided with a connecting groove 5 which is matched and connected with a connecting bulge 4 at the lower end of the adjacent middle section of prefabricated wall body, and in order to facilitate smooth transfer, the bottom of the bottom section of prefabricated wall body is provided with a pointed part 7; as shown in fig. 2, a connecting protrusion 4 is arranged at one end of the lower end head of the middle prefabricated wall body, and a connecting groove 5 is arranged at the upper end; as shown in figure 3, one end of the lower end of the prefabricated wall body of the top section is provided with a connecting bulge 4 which is connected with a connecting groove 5 at the upper end of the prefabricated wall body of the adjacent middle section in a matching way, the top of the prefabricated wall body of the top section is provided with a reserved steel bar 27, the middle of the top is provided with two vibrating steel plates 23, and the two vibrating steel plates 23 can be matched and clamped with a clamping plate of a vibrating hammer.

As shown in FIGS. 4 and 5, in order to facilitate connection and improve the connection firmness, the invention is characterized in that a convex connecting steel plate 8 is welded on the outer side of a convex main rib 10 at the width position of a connecting protrusion 4, a groove connecting steel plate 9 is welded on the outer side of a groove main rib 12 at the width position of a connecting groove 5, bolt holes are correspondingly arranged on the convex connecting steel plate 8 and the groove connecting steel plate 9, nuts 25 are arranged on the inner sides of the bolt holes of the groove connecting steel plate 9, in two adjacent butted prefabricated walls, the connecting protrusion 4 of one of the two adjacent prefabricated walls is connected with the connecting groove 5, and is fixedly connected with the nuts 25 after passing through the bolt holes of the convex connecting steel plate 8 and the groove connecting steel plate 9 from outside to inside by bolts 11, a protective layer 26 is coated on the outer surface of the convex connecting steel plate 8, two ends of the protective layer 26 extend to the connecting end surfaces of the two adjacent, the outer surface of the convex connecting steel plate 8 is protected, and the service life of the convex connecting steel plate is prolonged.

As shown in fig. 3, in order to prevent the whole prefabricated wall from being lowered in place in the lowering process, the two vibrating steel plates 23 are arranged at the top of the top section prefabricated wall, the two vibrating steel plates 23 can be matched and clamped with the clamping plates of the vibrating hammer, the vibrating hammer clamps the two vibrating steel plates 23 in the lowering process of the prefabricated wall, and the prefabricated wall is provided with power for lowering through vibration, so that smooth lowering is ensured; the four corners at the top and one side of each prefabricated wall are respectively provided with 4 lifting lugs 24, the four corners at the bottom of each prefabricated wall are correspondingly provided with 4 grooves matched with the lifting lugs 24, when the two prefabricated walls are connected, the lifting lugs 24 are directly installed on the corresponding grooves, so that the cutting process is prevented, the strength of the prefabricated wall can be increased, the 4 lifting lugs 24 at the top are used for vertical hoisting before lowering, and the 4 lifting lugs 24 at the side are used for hoisting in the transportation process.

As shown in fig. 6, the jacking positioning frame of the present invention comprises a base 14 for placing the jacking positioning frame on an inverted L-shaped guide wall, wherein the base 14 is provided with 4 jacking cylinders 13 and two horizontal adjusting cylinders 18, the 4 jacking cylinders 13 are provided with a supporting platform, the supporting platform comprises a jacking stress frame 15 placed on the jacking cylinders 13 and horizontal positioning frames 17 located at two sides of the jacking stress frame 15, and the distance between the two horizontal positioning frames 17 is greater than the width of the prefabricated wall; horizontal adjustment hydro-cylinder 18 inboard is connected with pulley mounting panel 28, and the inboard of pulley mounting panel 28 vertically is equipped with two sets of pulleys 29, during the installation of prefabricated wall body, adjust the distance between two pulley mounting panels 28 by horizontal adjustment hydro-cylinder 18 earlier, make the pulley 29 interval of both sides and the width matching of prefabricated wall body, pass corresponding installation fixed orifices 6 with the connecting rod again, the jacking atress frame 15 position on 4 jacking hydro-cylinders 13 upper portions is arranged in at the both ends of connecting rod, is equipped with reinforcing floor 16 on the jacking atress frame 15, is connected with last section of prefabricated wall body after will prefabricating the wall body fixed, and pulley 29 can guarantee that the prefabricated wall body is vertical to transfer when fixing a position prefabricated wall body.

As shown in FIG. 7, the wall brush of the present invention is used for cleaning the surfaces of the trapezoidal grooves 3 on both sides of the prefabricated wall body to remove the sludge on the surfaces, and comprises a brush holder 21 formed by fixedly connecting two mounting plates, a hanger plate 19 is fixedly arranged at the upper middle part of the brush holder 21, at least two hanging holes 1901 are respectively arranged at both ends of the hanger plate 19 and connected with a crane through the hanging holes 1901, at least two sets of reinforcing steel plates 20 are obliquely arranged in a cavity in the brush holder 21, a steel brush clamp plate 22 is arranged at least on one side of the brush holder 21, the structure of the steel brush clamp plate 22 is matched with the trapezoidal groove 3, and steel wires are arranged on the steel brush clamp plate 22 as steel brushes for brushing off the mud skin formed by the accumulation of the mud on the trapezoidal groove 3.

The invention relates to a construction method for manufacturing and casting a combined underground continuous wall, which comprises the following steps: constructing a guide wall matched with the designed continuous wall in width along the periphery of an underground structure or a high-rise building foundation pit designed on a drawing on the ground, dividing a groove section into a front width groove section (2 m) and a closed width groove section (6 m) which are combined at intervals, excavating a 2.8m groove section (adopting a prefabricated wall body which is slightly smaller than the designed width by 2-4 cm) in the guide wall in a slurry wall protection state by using a grooving machine, then putting the prefabricated wall body into the front width groove section, then completing the construction of all the front width groove sections of 2m in sequence, excavating a 6m closed width groove section in the guide wall in a slurry wall protection state by using the grooving machine, then pouring concrete in a guide wall groove filled with slurry by using a conduit method, gradually pouring the concrete from the bottom of the groove section upwards, simultaneously replacing the slurry, forming a reinforced concrete wall section in the ground, and then completing all the closed groove sections in sequence, until forming a whole continuous closed underground continuous wall, the concrete construction method is as follows:

1) selecting a grooving machine with the same width and size as the standard underground continuous wall designed by the drawing, and prefabricating a prefabricated wall body with the width matched with the design width of the drawing;

2) excavating a guide wall ditch with the depth of 1.5-2.5m and the length of each segment of 15-20 m, respectively pouring inverted L-shaped guide walls on two sides of the guide wall ditch, adding deformed steel bar single-layer meshes with the diameter of 12mm into an inverted L-shaped steel plate, and enabling the longitudinal and transverse spacing of the deformed steel bar single-layer meshes to be 200mm multiplied by 200 mm; the distance between the two inverted L-shaped guide walls is the same as the width of a standard underground continuous wall designed by a drawing, each section of guide wall channel is connected to form a closed guide wall along the side line of the foundation pit, the depth of the inverted L-shaped guide wall is equal to that of the guide wall channel, and the width of the top of the inverted L-shaped guide wall extending to the ground is 0.8-1.2 m;

3) after the inverted L-shaped guide wall is shaped, alternately dividing the first width groove section and the closed width groove section at intervals according to different intervals; under the states of an inverted L-shaped guide wall and a slurry retaining wall, excavating the advanced groove section to the designed depth by using the grooving machine in the step 1) to obtain the advanced construction groove section of the underground diaphragm wall, wherein the width of the advanced groove section is 2m, and the width of the closed groove section is 6 m;

4) firstly, installing jacking positioning frames on an inverted L-shaped guide wall, wherein the structure of the jacking positioning frames is as shown in FIG. 4, before the prefabricated wall is installed, a horizontal adjusting oil cylinder 18 is used for adjusting the distance between two horizontal positioning frames 17 to enable the distance to be matched with the width of the prefabricated wall, a gap is reserved, the width of the prefabricated wall is 2000mm and is determined as the width, the length of the prefabricated wall is 12m, and the width of the prefabricated wall is slightly smaller than the design width of a continuous wall (the width is reduced by 2-4cm according to different geological conditions); putting a prefabricated wall body (with standard length of 12M) with prefabricated bottom sections into the groove sections, then putting corresponding mounting and fixing holes 6 through which connecting rods pass, placing two ends of each connecting rod on a jacking stress frame 15, butting the connecting rods with the previous prefabricated wall body, sequentially lowering the connecting rods to a designed depth, inserting the tip parts 7 at the bottom of the prefabricated wall body with the bottom of each bottom section into the bottom, finally butting the prefabricated wall body with the top sections, lowering the prefabricated wall body to the designed depth, pouring concrete into the square through long holes 2 of the prefabricated wall body, plugging the square through long holes 2, and completing construction of the advanced groove sections, wherein when the prefabricated wall body is transported, the sections are connected with one another by M30 bolts;

5) excavating to a designed depth by using the trenching machine in the step 1) under the states of the inverted L-shaped guide wall and the slurry retaining wall to obtain a closed construction groove section of the underground continuous wall;

6) integrally manufacturing a reinforcement cage on site in advance, paving a bed mould at the bottom of a reinforcement cage manufacturing platform in a longitudinal and transverse mode by adopting 10# channel steel, placing the prefabricated reinforcement cage into a groove section, and pouring concrete into the groove section in which the reinforcement cage is placed by using a guide pipe method to form a reinforced concrete wall section;

7) and (5) repeating the steps (5) and (6) until the reinforced concrete wall section (the closed slot section) is completely constructed, and obtaining the underground continuous wall required by the design of the drawing.