CN115949055A - Construction method of foundation pit continuous wall - Google Patents

Abstract

The invention discloses a construction method of a foundation pit continuous wall, which relates to the technical field of deep foundation pit support of constructional engineering.A starting well and a receiving well are respectively arranged at four corners of a predicted foundation pit, continuous wall prefabricated blocks are hoisted in the starting well in sections, a plurality of sections of continuous wall prefabricated blocks form continuous wall prefabricated blocks through temporary fixing measures, each time the excavation of a section of groove section is completed, one section of continuous wall prefabricated block is immediately pushed through a pushing system, and the installation and pushing of the continuous wall prefabricated blocks are repeated until the first section of continuous wall prefabricated block is pushed to the receiving well; and then, turning the pushing direction of the pushing device, continuing to perform continuous wall pushing construction between the starting well and the other receiving well, and after the pushing construction of the continuous walls is completed between all the starting wells and all the receiving wells, performing end treatment on the adjacent continuous walls in the wells. Compared with the prior art, the construction method of the foundation pit continuous wall can reduce the construction difficulty of the continuous wall and save the construction period.

Description

Construction method of foundation pit continuous wall

Technical Field

The invention relates to the technical field of deep foundation pit supporting in constructional engineering, in particular to a construction method of a foundation pit continuous wall.

Background

The underground continuous wall is the strongest and most effective large-scale foundation pit supporting form in the foundation pit engineering at present, and utilizes various trenching machines to excavate narrow and deep trenches in the ground by means of the wall protection effect of slurry, and appropriate materials are poured in the trenches to form a continuous underground wall body with the functions of seepage prevention, water prevention, soil retaining and bearing. The construction vibration is small, the wall rigidity is large, the integrity is good, the construction speed is high, the earth and stone space can be saved, the method can be used for constructing deep foundation pit support in dense building groups and carrying out reverse construction, and the method can be used for construction in various geological conditions including sandy soil layers and gravel layers with the particle size of less than 50 mm. The method is suitable for building basements, underground shopping malls, parking lots, underground oil depots, retaining walls, deep foundations of high-rise buildings, reverse construction building enclosures and deep ponds and pits of industrial buildings; a shaft, etc. At present, the construction of the underground continuous wall mainly adopts a cast-in-place concrete construction process, but the construction process has the following problems: 1. under some special geological conditions (such as very soft mucky soil, deep sand layers and scouring and depositing layers containing boulders), the construction difficulty is very high; 2. the underground continuous wall process is invisible, the processing difficulty of the joint positions of adjacent concrete sections is high, and the problems that adjacent wall sections cannot be aligned and water leakage easily occur; 3. the cast-in-place structure wall surface has poor quality, and the phenomenon of steel bar exposure often occurs; 4. in urban construction, the treatment of waste slurry is troublesome.

Disclosure of Invention

The present invention aims to solve at least to some extent one of the above-mentioned technical problems of the prior art. Therefore, the embodiment of the invention provides a construction method of a foundation pit continuous wall, which can reduce the construction difficulty of the continuous wall, save the construction period and further solve the problems that adjacent continuous wall sections cannot be aligned and leak water.

The construction method of the foundation pit continuous wall provided by the embodiment of the invention comprises the following steps of:

s1, two starting wells and two receiving wells are arranged, connecting lines of the two starting wells and the two receiving wells surround to form a rectangle, and the two starting wells are arranged diagonally in the rectangle;

s2, constructing two rows of guide walls between the originating well and the receiving well;

s3, arranging a pushing system in the starting well, and producing and manufacturing prefabricated blocks of the continuous wall;

s4, splicing the continuous wall prefabricated blocks into continuous wall prefabricated blocks, and constructing the continuous wall from the starting well to one receiving well, wherein during construction, a groove section is dug between two rows of guide walls, and the continuous wall prefabricated blocks are pushed through a pushing system until the first section of the continuous wall prefabricated blocks enter the receiving well;

s5, reversing the direction of the pushing system, and constructing the continuous wall between the starting well and the other receiving well, wherein during construction, a groove section is excavated between the two rows of guide walls, and the continuous wall prefabricated blocks are pushed through the pushing system until the first section of the continuous wall prefabricated blocks enter the receiving well;

s6, after the continuous walls between the starting well and the receiving well are pushed in place, carrying out cast-in-place construction on end portions of two adjacent rows of continuous walls;

s7, removing the pushing device in the originating well, and backfilling soil in the originating well and the receiving well.

According to the construction method of the foundation pit continuous wall, in the step S4 or the step S5, the two starting wells respectively face different receiving wells to synchronously construct the continuous wall.

According to the construction method of the foundation pit continuous wall, when the continuous wall is constructed, after the assembly of the first section of continuous wall precast block is completed, the first section of continuous wall precast block is placed in the starting well, wherein the advancing end of the first section of continuous wall precast block is provided with the pushing head, after the excavation of the first section of groove section is completed, the first section of continuous wall precast block is pushed into the first section of groove section through the pushing system, and each section of groove section is excavated subsequently, one section of continuous wall precast block is added into the starting well, and the continuous wall is formed by splicing a plurality of sections of continuous wall precast blocks.

According to the construction method of the foundation pit continuous wall, when the first section of continuous wall precast block is close to the receiving well, a first slotted hole is formed in the wall of the receiving well in a water drilling or rope sawing mode, a steel structure door pocket used for receiving the first section of continuous wall precast block is installed in the first slotted hole, and a high-pressure rotary jet grouting pile is constructed outside the outlet of the first slotted hole.

According to the construction method of the foundation pit continuous wall provided by the embodiment of the invention, in the step S3, after the pushing system is installed, a second slotted hole is formed in the wall of the starting well in a water drilling or rope sawing mode, the steel structure door pocket is installed on the periphery of the second slotted hole, and a high-pressure jet grouting pile is constructed at the inlet of the second slotted hole.

According to the construction method of the foundation pit continuous wall, grouting is performed between the steel structure door pocket and the continuous wall after the continuous wall between the starting well and the receiving well is estimated to be in place.

According to the construction method of the foundation pit continuous wall, the pushing system comprises a three-dimensional pushing assembly, a sliding rail assembly and a controller for controlling the three-dimensional pushing assembly, the controller is arranged outside the starting well, a back wall for installing the three-dimensional pushing assembly is arranged in the starting well, the sliding rail assembly is arranged at the bottom of the starting well, and the sliding rail assembly is used for assisting sliding of the continuous wall precast block.

According to the construction method of the foundation pit continuous wall, the slide rail assembly comprises a groove type slide rail and a bottom plate, the bottom plate is made of reinforced concrete, the groove type slide rail is U-shaped and is fixed on the bottom plate, and steel balls are paved in the groove type slide rail.

According to the construction method of the foundation pit continuous wall, the side surfaces of the continuous wall prefabricated blocks are provided with connecting channels for butt joint, two adjacent sections of the continuous wall prefabricated blocks are butted through an arc-shaped bolt, the arc-shaped bolt penetrates through the connecting channels, and grouting holes and round holes are formed between the two ends of the continuous wall prefabricated blocks.

According to the construction method of the foundation pit continuous wall, the guide wall is further provided with a guide device, the guide device comprises a portal frame erected between two rows of the guide walls and a sliding component used for assisting the portal frame to perform sliding motion, and a position, aligned with the groove section, of the portal frame is provided with a limiting piece.

Based on the technical scheme, the embodiment of the invention at least has the following beneficial effects: according to the technical scheme, an originating well and a receiving well are respectively arranged at four corners of a predicted foundation pit, continuous wall prefabricated blocks are hoisted in the originating well in a segmented mode, multiple sections of continuous wall prefabricated blocks form continuous wall prefabricated blocks through temporary fixing measures, once the excavation of one section of groove section is completed, one section of continuous wall prefabricated block is pushed through a pushing system, and the installation and pushing of the continuous wall prefabricated block are repeated until the first section of continuous wall prefabricated block is pushed to the receiving well; and then, turning the pushing direction of the pushing device, continuing to perform continuous wall pushing construction between the starting well and the other receiving well, and after the pushing construction of the continuous walls is completed between all the starting wells and all the receiving wells, performing end treatment on the adjacent continuous walls in the wells. Compared with the prior art, the construction method can be used for construction under some special geological conditions (such as soft mucky soil, deep sand layers and drift-containing washing and depositing layers), and is simple in construction. The prefabricated blocks of the diaphragm wall are prefabricated outside the field, the prefabricated blocks of the diaphragm wall are assembled in sections on the field, after the pushing system is used for pushing the prefabricated blocks in place, the end parts of the prefabricated blocks are cast in place by reinforced concrete, and finally a closed underground diaphragm wall structure is formed.

Drawings

The invention is further described below with reference to the drawings and examples;

FIG. 1 is a first schematic diagram of a diaphragm wall construction between an originating well and a receiving well in an embodiment of the present invention;

FIG. 2 is a second schematic diagram of a diaphragm wall construction between an originating well and a receiving well in an embodiment of the present invention;

FIG. 3 is a third schematic diagram of the construction of a diaphragm wall between an originating well and a receiving well in an embodiment of the present invention;

FIG. 4 is a fourth schematic illustration of the construction of a diaphragm wall between an originating well and a receiving well in an embodiment of the present invention;

FIG. 5 is a schematic view showing the connection between the originating well and the thruster in the embodiment of the present invention;

FIG. 6 is a schematic diagram of a second connection between the launch well and the thruster in an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a slide rail assembly according to an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of prefabricated blocks of the continuous wall according to the embodiment of the present invention;

FIG. 9 is a schematic view of a block of prefabricated wall sections according to an embodiment of the present invention;

FIG. 10 is a first schematic view of a guide device according to an embodiment of the present invention;

fig. 11 is a second schematic structural diagram of a guiding device according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings only for the convenience of description of the present invention and simplification of the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

The underground continuous wall is a foundation engineering, and adopts a trenching machine on the ground, and under the condition of slurry wall protection, a long and narrow deep groove is excavated along the peripheral axis of the deep excavation engineering, after the groove is cleaned, a steel reinforcement cage is hung in the groove, then underwater concrete is poured by using a conduit method to construct a unit groove section, and the steps are carried out section by section, so that a continuous reinforced concrete wall is constructed underground to be used as a structure for intercepting water, preventing seepage, bearing and retaining water. However, the existing forming method for mainly adopting cast-in-place concrete for the underground continuous wall has the following defects: 1. the construction difficulty is very high under some special geological conditions (such as very soft mucky soil, deep sand layers and scouring and depositing layers containing boulders); 2. the underground continuous wall process is invisible, the processing difficulty of the joint positions of adjacent concrete sections is high, and the problems that the adjacent wall sections cannot be aligned and water leakage easily occur; 3. the cast-in-place structure wall surface has poor quality, and the phenomenon of steel bar exposure often occurs; 4. in urban construction, the treatment of waste slurry is troublesome.

As shown in fig. 1, an embodiment of the present invention provides a novel foundation pit continuous wall construction method, which can perform efficient, fast and safe continuous wall construction. Specifically, the method comprises the following steps:

s1, two originating wells 110 and two receiving wells 120 are arranged, connecting lines of the two originating wells 110 and the two receiving wells 120 surround to form a rectangle, and the two originating wells 110 are arranged diagonally in the rectangle;

s2, constructing two rows of guide walls 130 between the originating well 110 and the receiving well 120;

s3, arranging a jacking system in the starting well 110, and producing and manufacturing the prefabricated partition blocks 310 of the continuous wall;

s4, as shown in FIG. 2, splicing the continuous wall prefabricated blocks 310 into the continuous wall prefabricated blocks 300, and constructing the continuous wall 500 from the starting well 110 to one receiving well 120, wherein during construction, a groove section is dug between two rows of guide walls 130, and the continuous wall prefabricated blocks 300 are pushed through a pushing system until the first section of continuous wall prefabricated blocks 300 enter the receiving well 120;

s5, reversing the direction of the pushing system, and constructing a continuous wall 500 from the starting well 110 to the other receiving well 120, wherein during construction, a groove section is dug between the two rows of guide walls 130, and the continuous wall prefabricated block 300 is pushed through the pushing system until the first section of continuous wall prefabricated block 300 enters the receiving well 120;

s6, as shown in figures 3 and 4, after the continuous walls 500 between the originating well 110 and the receiving well 120 are pushed to the right positions, the construction of the cast-in-place sections 140 at the end parts of the two adjacent rows of continuous walls 500 is carried out;

s7, removing the pushing devices in the originating well 110, and backfilling soil in the originating well 110 and the receiving well 120.

Specifically, the starting well 110 is used for installation, pushing and integrated construction of the continuous wall 500, the starting well 110 is of a reinforced concrete structure, the plane is square, the depth is determined according to the height of the continuous wall 500, and the construction is performed by adopting a sinking method or a reverse method. The four corners in the well are all provided with angle braces which are vertically arranged at intervals. When the open caisson method is used for constructing the initial well 110, concrete is poured after the steel bars are reserved, and when the initial well 110 is constructed by the reverse method, the construction is carried out synchronously along with the well wall. Two steel structure door pockets 111 are arranged in the well and are arranged on one side of the pushing direction of the continuous wall precast block 300 to assist in pushing the continuous wall precast block 300 and prevent water and external silt from entering the starting well 110. Before the installation of steel construction door pocket 111, arrange two rows of removable steel pipe concrete to propping, vertical interval arrangement is unanimous with the corner brace plane position, and the steel pipe fulcrum is by distribution beam and steel construction door pocket 111. A circle of closed rings are arranged from the top of the steel structure door pocket 111 to the top of the starting well, and the pushing construction of the continuous wall precast block 300 is not influenced.

The receiving well 120 is used for receiving and integrally constructing the continuous wall precast block 300, the receiving well 120 is of a reinforced concrete structure, the plane is square, the depth is determined according to the height of the continuous wall precast block 300, the top of the receiving well is higher than that of the continuous wall precast block 300, and the receiving well is constructed by adopting an open caisson method or a reverse method. An angle brace and a cross brace are arranged at one corner in the receiving well 120, the angle brace and the cross brace are arranged at intervals vertically, the receiving well is of a reinforced concrete structure, when the open caisson method is used for construction, concrete is poured after a reinforcing steel bar is reserved, and when the open caisson method is used for construction, construction is carried out synchronously along with the well wall. Two steel structure door pockets 111 are arranged in the receiving well 120 and are installed on one side of the pushing direction of the continuous wall precast block 300 to assist the receiving of the continuous wall precast block 300, and meanwhile, the receiving well can prevent water and external silt from entering the receiving well 120. A row of detachable steel pipe concrete diagonal braces are arranged in the receiving well 120, are vertically arranged at intervals and are staggered with the plane positions of the angle braces, and steel pipe fulcrums are beside the distribution beams and the door pocket of the well wall.

And hoisting the continuous wall prefabricated block 310 in the starting well 110 in a segmented manner, forming the continuous wall prefabricated block 300 by the continuous wall prefabricated block 310 through a temporary fixing measure, immediately pushing one section by a pushing system once one section is finished, and repeating the installation and pushing of the continuous wall prefabricated block 300. It should be noted that, the two originating wells 110 are respectively directed to different receiving wells 120 to perform synchronous construction of the continuous wall 500, so that the construction progress of the continuous wall 500 can be accelerated, the construction period can be shortened, and the underground continuous wall does not need to be set such as standing like a cast-in-place underground continuous wall.

In some embodiments, during the construction of the continuous wall, after the first section of the continuous wall precast block 300 is assembled, the first section of the continuous wall precast block 300 is placed in the starting well 110, wherein the advancing end of the first section of the continuous wall precast block 300 is provided with the pushing head 230, after the first section of the groove section is excavated, the first section of the continuous wall precast block 300 is pushed into the first section of the groove section through the pushing system, and after each subsequent section of the groove section is excavated, one section of the continuous wall precast block 300 is newly added into the starting well 110, and the continuous wall 500 shown in fig. 3 or fig. 4 is assembled by the sections of the continuous wall precast blocks 300.

Wherein, top pusher 230 is by the steel plate, the board is tightened to the steel, angle steel and channel-section steel welding are constituteed, the front end is semi-circular, the surface is the steel plate, it is unanimous with underground continuous wall highly, the bottom is sealed, the top is opened, top angle steel passes through welded connection with guide system H shaped steel fixed, top pusher 230 adopts circular arc or wide design behind the preceding narrow, avoid earth and grit to push up the gathering in the place ahead, reduce continuous wall prefabricated section 300 and push up the resistance in the place ahead, can protect the reinforcing bar that first section continuous wall prefabricated section 300 was reserved, ensure to realize the cast-in-place integrative construction of continuous wall 500 tip.

Further, when the first section of continuous wall prefabricated block 300 is close to the receiving well 120, a first slotted hole is formed in the wall of the receiving well 120 in a water drilling or rope sawing mode, a steel structure door pocket 111 used for assisting in receiving the first section of continuous wall prefabricated block 300 is installed in the first slotted hole, a high-pressure rotary spraying pile 112 is constructed outside an outlet of the first slotted hole, the high-pressure rotary spraying pile 112 can reinforce the ground surface and effectively guide the continuous wall prefabricated block 300 into the steel structure door pocket 111, it needs to be noted that after the pushing system is installed, a second slotted hole is formed in the wall of the starting well 110 in a water drilling or rope sawing mode, the door pocket 111 is installed on the periphery of the second slotted hole, a high-pressure rotary spraying pile 112 is constructed at an inlet of the second slotted hole, and the high-pressure rotary spraying pile 112 can reinforce the ground surface and effectively guide the continuous wall prefabricated block 300 into the steel structure door pocket 111. The steel structure door pocket 111 is formed by processing steel plates and steel ribs and is mainly used for pushing the prefabricated block 300 of the continuous wall out of a hole and entering the hole, a groove type steel ball sliding rail is arranged at the bottom, a rubber water stop curtain is arranged on the periphery of the groove type steel ball sliding rail, and the height of the steel structure door pocket 111 of the receiving well 120 is higher than that of the steel structure door pocket 111 of the starting well 110. The steel structure door pocket 111 is installed in the starting well 110 or the receiving well 120 and used as a passage opening for pushing the continuous wall precast block 300 out of or into the well, and meanwhile, the steel structure door pocket 111 can play a role in preventing soil outside the well from entering the well and protecting the wall of the well after opening from being damaged by collision.

In some embodiments, after the continuous wall 500 between the initiation well 110 and the receiving well 120 is estimated to be in place, grouting is performed between the steel structure door pocket 111 and the continuous wall 500, so that the continuous wall 500 is completely connected with the steel structure door pocket 111, and meanwhile soil outside the well is prevented from entering the well, so that preparation is made for subsequent construction.

In other embodiments, as shown in fig. 5 and 6, the pushing system includes a three-dimensional pushing assembly 220, a sliding rail assembly 150 and a controller for controlling the three-dimensional pushing assembly 220, the controller is disposed outside the starting well 110, a back wall 210 for installing the three-dimensional pushing assembly 220 is disposed in the starting well 110, the sliding rail assembly 150 is disposed at the bottom of the starting well 110, the sliding rail assembly 150 is used for assisting the sliding of the continuous wall precast block 300, specifically, as shown in fig. 7, the sliding rail assembly 150 includes a groove-type sliding rail 152 and a bottom plate 151, the bottom plate 151 is made of reinforced concrete, the groove-type sliding rail 152 is U-shaped and fixed to the bottom plate 151, and steel balls 153 are laid in the groove-type sliding rail 152. The controller drives the three-dimensional pushing assembly 220 to generate horizontal thrust, so that the continuous wall prefabricated block 300 in the starting well 110 can be conveniently pushed into the groove section from the well, the power problem that the assembled continuous wall prefabricated block 300 enters the soil body is solved, the resistance of the three-dimensional pushing assembly 220 to push the continuous wall prefabricated block 300 can be reduced due to the arrangement of the sliding rail assembly 150, and the pushing efficiency is effectively improved.

As shown in fig. 8 and 9, the side of the prefabricated wall segment 310 is provided with a connecting channel 314 for butt joint, and two adjacent prefabricated wall segments 310 are butt-jointed by an arc bolt 313, wherein the arc bolt 313 passes through the connecting channel 314, a grouting hole 311 and a circular hole 312 are provided between two ends of the prefabricated wall segment 310, when the prefabricated wall segment 300 is assembled into the continuous wall 500, concrete is poured into the grouting hole 311, and a steel pipe is inserted into the circular hole 312, and concrete is also poured into the steel pipe, so that the prefabricated wall segments 310 can be more firmly connected together, and the waterproof effect of the continuous wall 500 is increased. The prefabricated assembly type continuous wall prefabricated blocks 310 are prefabricated outside the field, are assembled into the continuous wall prefabricated blocks 300 in sections on the field, are pushed in place by the pushing system, and are cast in place by reinforced concrete at the end to form a cast-in-place section 140, so that a closed continuous wall 500 structure is finally formed. The continuous wall 500 is vertically layered and horizontally segmented, the upper layer is a top adjusting block, the middle part and the bottom part are standard blocks, connecting steel bars are reserved on one sides of the first section of continuous wall precast block 300 and the last section of continuous wall precast block 300, and the cast-in-place section 140 is convenient to construct and connect. The prefabricated continuous wall prefabricated block 300 can be prefabricated in a factory or a site in advance, and compared with the original cast-in-place construction, the prefabricated continuous wall prefabricated block is more controllable in quality and more guaranteed; the whole construction process is dry operation construction, so that the waterproof and connection treatment among all the sections of the continuous wall precast block 300 is more convenient, and the quality and the effect are more visual; the method of the continuous wall precast block 300 realizes the assembly type construction of the underground continuous wall, the size specification and the connection mode of the wall body can be adjusted according to the geological condition, the construction is adjustable, and the manufacturing cost is more controllable; the difficult problem that the vertical whole requirement of the underground continuous wall with larger depth is high is effectively solved by the linking mode of the wall body.

In addition, as shown in fig. 10 and 11, a guide device 400 is further disposed on the guide wall 130, the guide device 400 includes a gantry 420 erected between the two rows of guide walls 130 and a sliding member for assisting the gantry 420 to perform sliding movement, and a position of the gantry 420 aligned with the groove segment is provided with a limiting member 430. The guide wall 130 is used for controlling the groove section excavation and the pushing direction of the continuous wall prefabricated block 300, the sliding component is used for assisting the sliding of the portal frame 420, and the limiting part 430 is used for controlling the overall elevation of the continuous wall prefabricated block 300. The guide wall 130 is a reinforced concrete structure, and the depth of the guide wall 130 exceeds the top of the prefabricated block 300 of the continuous wall, and the width is determined according to actual conditions. The sliding component is composed of a prefabricated track plate and a groove rail 410, the prefabricated track plate is of a cuboid reinforced concrete structure and is arranged on the guide wall, the groove rail 410 is arranged below and hoisted and moved along the pushing direction, the groove rail 410 is processed into a groove type structure by a thick steel plate, and the groove type structure is internally provided with a steel ball 411 and lubricating oil and is hoisted and moved along the pushing direction. Portal frame 420 is formed by the I-steel, the channel-section steel, H shaped steel welding combination, and the bottom sprag is formed by welding two sets of I-steel side by side, and the middle part is formed by the multiunit welding side by side, and vertical welding fixes on the top supports the I-steel, and the channel-section steel concave surface for the top vertical welding is on middle part I-steel group down, and equidistant vertical welding channel-section steel supports inboard I-steel belly at the top, forms stable structure with the top. Two H-shaped steels are welded at the bottoms of the first two sections of transverse H-shaped steels to form a limiting part 430, and the length of the limiting part 430 is the distance from the top of the continuous wall precast block 300 to the bottom of the middle H-shaped steel. The arrangement of the guide wall 130 and the guide device 400 can control the pushing direction and elevation of the continuous wall precast block 300 in the horizontal direction. The guide wall 130 may control the pushing direction of the prefabricated continuous wall block 300 to be performed in a predetermined direction, and may provide support for the groove rail 410. The sliding member reduces the resistance of the gantry 420 in the moving process, also reduces the resistance of the pushing process, and simultaneously ensures that the moving direction of the guide device 400 in the pushing process is consistent with that of the continuous wall precast block 300. The guide device 400 can prevent the continuous wall precast block 300 from sinking to generate larger resistance by hoisting the first section of the continuous wall precast block 300, and the limit piece 430 limits the continuous wall precast block 300 to float upwards, so that the aims of controlling the elevation of the top pushing direction of the underground continuous wall and reducing the resistance are fulfilled. Specifically, the guide wall 130 and the guide device 400 solve the problems of resistance reduction, direction and elevation control when the assembled prefabricated wall block 300 is pushed horizontally.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention.

Claims (10)

1. A construction method of a foundation pit continuous wall is characterized by comprising the following steps:

s1, two originating wells (110) and two receiving wells (120) are arranged, the connecting lines of the two originating wells (110) and the two receiving wells (120) surround to form a rectangle, and the two originating wells (110) are arranged diagonally in the rectangle;

s2, constructing two rows of guide walls (130) between the originating well (110) and the receiving well (120);

s3, arranging a jacking system in the starting well (110), and producing and manufacturing the prefabricated partition (310) of the continuous wall;

s4, splicing the continuous wall prefabricated blocks (310) into continuous wall prefabricated blocks (300), and constructing the continuous wall (500) between the starting well (110) and one receiving well (120), wherein during construction, a groove section is dug between two rows of guide walls (130), and the continuous wall prefabricated blocks (300) are pushed by a pushing system until the first section of the continuous wall prefabricated blocks (300) enter the receiving well (120);

s5, reversing the direction of the pushing system, and constructing the continuous wall (500) between the starting well (110) and the other receiving well (120), wherein during construction, a groove section is dug between two rows of guide walls (130), and the continuous wall precast block (300) is pushed through the pushing system until the first section of the continuous wall precast block (300) enters the receiving well (120);

s6, after the continuous walls (500) between the originating well (110) and the receiving well (120) are pushed to the right positions, constructing end cast-in-place sections (140) of two adjacent rows of the continuous walls (500);

s7, removing the pushing devices in the starting well (110), and backfilling soil in the starting well (110) and the receiving well (120).

2. The construction method of a foundation pit continuous wall according to claim 1, characterized in that: in step S4 or step S5, the two originating wells (110) are respectively oriented to different receiving wells (120) for synchronous construction of the continuous wall (500).

3. The construction method of a foundation pit continuous wall according to claim 2, characterized in that: when the construction of the continuous wall is carried out, the first section of the continuous wall precast block (300) is placed in the starting well (110) after the assembly is completed, wherein the pushing head (230) is installed at the advancing end of the first section of the continuous wall precast block (300), after the groove section is excavated, the first section of the continuous wall precast block (300) is pushed into the first section of the groove section through the pushing system, one section of the continuous wall precast block (300) is newly added into the starting well (110) every time the groove section is excavated subsequently, and the continuous wall precast blocks (300) are spliced into the continuous wall (500) through multiple sections.

4. The construction method of a foundation pit continuous wall according to claim 1, characterized in that: first festival diaphragm wall prefabricated section (300) are close to during receiving well (120), adopt the mode of water drilling or rope saw to be in first slotted hole is seted up to the wall of a well of receiving well (120), first slotted hole is installed and is used for receiving the first festival the steel construction door pocket (111) of diaphragm wall prefabricated section (300), the export of first slotted hole is under construction outward and is had high-pressure jet grouting stake (112).

5. The construction method of a foundation pit continuous wall according to claim 4, characterized in that: in the step S3, after the pushing system is installed, a second slotted hole is formed in the wall of the starting well (110) in a water drilling or rope sawing mode, the steel structure door pocket (111) is installed on the periphery of the second slotted hole, and a high-pressure jet grouting pile (112) is constructed at the entrance of the second slotted hole.

6. The construction method of a foundation pit continuous wall according to claim 5, characterized in that: after the continuous wall (500) between the originating well (110) and the receiving well (120) is pushed into position, grouting treatment is carried out between the steel structure door pocket (111) and the continuous wall (500).

7. The construction method of a foundation pit continuous wall according to claim 1, characterized in that: the jacking system comprises a three-dimensional jacking assembly (220), a sliding rail assembly (150) and a controller for controlling the three-dimensional jacking assembly (220), the controller is arranged outside the starting well (110), a back wall (210) used for installing the three-dimensional jacking assembly (220) is arranged in the starting well (110), the sliding rail assembly (150) is arranged at the bottom of the starting well (110), and the sliding rail assembly (150) is used for assisting sliding of the continuous wall prefabricated block (300).

8. The construction method of a foundation pit continuous wall according to claim 7, characterized in that: the sliding rail assembly (150) comprises a groove type sliding rail (152) and a bottom plate (151), the bottom plate (151) is made of reinforced concrete, the groove type sliding rail (152) is U-shaped and fixed on the bottom plate (151), and steel balls (153) are laid in the groove type sliding rail (152).

9. The construction method of a foundation pit continuous wall according to claim 1, characterized in that: the side surface of the prefabricated partition wall block (310) is provided with a connecting channel (314) for butt joint, two adjacent prefabricated partition wall blocks (310) are butted through an arc bolt (313), the arc bolt (313) penetrates through the connecting channel (314), and a grouting hole (311) and a round hole (312) are arranged between two ends of the prefabricated partition wall block (310).

10. The construction method of a foundation pit continuous wall according to claim 1, characterized in that: the guide wall (130) is further provided with a guide device (400), the guide device (400) comprises a portal frame (420) erected between the two rows of guide walls (130) and a sliding component used for assisting the portal frame (420) to perform sliding motion, and a limiting part (430) is arranged at the position, aligned with the groove section, of the portal frame (420).

Images