CN209179021U - A foundation pit row pile support system - Google Patents

Abstract

A pile row support system for a foundation pit, comprising a diagonally braced pile foundation cap, a pile row structure, and several sets of oblique supports supported between the diagonally braced pile foundation cap and the pile row structure; the diagonally braced pile foundation The cap includes a supporting platform directly below the structural wall and supporting piles supported at the bottom of the supporting platform. The pile row structure includes a row of piles, a crown beam arranged on the top surface of the row of piles, and a pile facing the foundation pit in the middle of the row of piles. The lumbar beam on the side, each set of oblique supports includes a steel diagonal brace one arranged between the crown beam and the supporting platform. The utility model has a heavy construction task in the underground structure and a tight construction period, and the surrounding environment is complex, and the support safety required by the design will be very high. The steel diagonal bracing based on the pile cap is used to act on the crown beam and the waist beam of the pile row. It can meet the requirements of most foundation pit support, and at the same time replace the horizontal support with oblique support, thus solving the problem of cumbersome procedures such as the removal of horizontal support that affect the construction of the foundation pit, and greatly saving the construction period.

Description

A foundation pit row pile support system

technical field

The utility model belongs to the field of foundation pit support, in particular to a foundation pit row pile support system.

Background technique

With the growth of the city, it has become inevitable to develop large-scale underground space in combination with urban construction and renovation. These deep and large foundation pits are often close to buildings, traffic arteries, subway tunnels and various underground pipelines. The construction site is tight and the construction conditions are complex. Due to the tight construction period, all these make the design and construction of foundation pit engineering more and more difficult. At present, the main forms of foundation pit support include natural slope, soil nail wall, single (double) row of piles, underground diaphragm wall, etc., but due to Due to the complexity around the foundation pit, the traditional or single support form can no longer fully meet the needs of the foundation pit support. In the case of using row piles, adding a horizontal force can effectively enhance the safety of the support, but the traditional The form of horizontal support seriously affects the construction period and the construction is difficult.

Utility model content

The purpose of this utility model is to provide a foundation pit row pile support system, to solve the technical problem that the single support method in the prior art has no way to meet the needs of foundation pit support; and to solve the problem that the traditional horizontal support form seriously affects the construction period and The difficulty of construction.

In order to achieve the above object, the utility model adopts the following technical solutions:

A foundation pit row pile support system is characterized in that: it includes a diagonally braced pile foundation cap, a pile row structure, and several groups of oblique supports supported between the diagonally braced pile foundation cap and the pile row structure; The inclined pile foundation cap includes a supporting platform directly below the structural wall and supporting piles supported at the bottom of the supporting platform. The pile row structure includes a pile row, a crown beam arranged on the top surface of the pile row, and a Towards the waist beam on the side of the foundation pit, each set of oblique supports includes a steel diagonal brace 1 arranged between the crown beam and the support platform.

Further preferably, each set of diagonal supports further includes the second steel diagonal brace arranged between the waist beam and the support platform, the first steel diagonal brace and the second steel diagonal brace pass through the structural wall, and both It is formed by splicing several steel pipe sections through flanges.

Further, the top surface of the support platform is a plane, and the plane is provided with an inwardly recessed receiving groove with a triangular cross-section. Slanting bracing is a parallel back-slanting supporting surface, and the facing inclined supporting surface is provided with a pre-embedded steel plate 1, and one end of the steel slanting bracing is provided with a flexible joint 1, and one end of the flexible joint is embedded with the support The steel plates are fixed by bolts.

Further, the end face of the support platform facing the pile row structure is an inclined plane perpendicular to the steel diagonal brace two, the end of the steel diagonal brace two is provided with the movable head two, and the support embedded steel plate two is provided on the inclined surface, The second movable head and the second embedded steel plate of the support are fixed by bolts.

Further, the first steel diagonal brace and the second steel diagonal brace of each group of diagonal supports are located on the same vertical plane.

Further, the foundation pit row pile support system also includes a central support lattice column for supporting the first steel diagonal brace and the second steel diagonal brace, and the central support lattice column includes an upper steel column and a lower column pile, so The lower column piles are reinforced concrete bored piles.

Further, the end of the steel diagonal brace facing the crown beam is welded and fixed to the embedded steel plate fixed on the crown beam, and the end of the steel diagonal brace facing the waist beam is connected to the embedded steel plate fixed on the waist beam Welding fixed.

Further, a circle of water-proof steel plates is welded to the part where the first steel diagonal brace and the second steel diagonal brace pass through the structural side wall of the structural wall, and the bottom plate of the structural wall allows the first steel diagonal brace and the second steel diagonal brace to pass through The parts are equipped with a long post-casting belt.

Compared with the prior art, the utility model has the following characteristics and beneficial effects:

The utility model has a heavy construction task in the underground structure and a tight construction period, and the surrounding environment is complex, so the safety of the support required by the design will be very high. The steel diagonal bracing based on the pile cap is used to act on the crown beam and the waist beam of the pile row. It can meet the requirements of most foundation pit support, and at the same time replace horizontal support with oblique support, thus solving the problem of cumbersome procedures such as horizontal support removal affecting the construction of foundation pit, and greatly saving the construction period.

Through the innovative method of post-casting strips left at the oblique support position on the bottom plate of the structural wall, the hidden danger of water seepage caused by the direct removal of the steel diagonal braces and then waterproof sealing is reduced. When it is removed directly, it reduces the loss and waste of materials caused by cutting.

The utility model has the characteristics of safety and applicability, has good popularization and practical value, and can produce good economic benefits after being widely popularized and applied.

Description of drawings

Fig. 1 is the structural representation of a kind of foundation pit row pile supporting system of the utility model;

Fig. 2 is a schematic diagram of the splicing structure of the steel brace 1 involved in the utility model;

Fig. 3 is a schematic cross-sectional structure diagram of Fig. 2;

Fig. 4 is a schematic diagram of the connection structure of the steel diagonal brace 2 and the joint head 2 involved in the present invention;

Fig. 5 is a schematic diagram of the connection structure between the steel brace one and the crown beam involved in the present invention.

Reference signs: 1-structural wall; 2-supporting platform; 3-supporting piles; 4-row piles; 5-crown beam; 6-waist beam; -flange; 10-hanging ring; 11-accepting groove; 111-facing inclined support surface; 112-back inclined support surface; 13-support embedded steel plate 2; Lattice column; 17-active head one.

Detailed ways

In order to make the technical means, innovative features, goals and effects achieved by the utility model easy to understand, the utility model will be further described below.

The embodiments described here are specific specific implementations of the present utility model, and are used to illustrate the concept of the present utility model. They are all explanatory and exemplary, and should not be construed as limitations on the implementation of the present utility model and the scope of the present utility model. limit. In addition to the embodiments described here, those skilled in the art can also adopt other obvious technical solutions based on the claims of the application and the contents disclosed in the description, and these technical solutions include adopting any obvious changes made to the embodiments described here. Replacement and modified technical solutions.

A pile row support system for a foundation pit, comprising a diagonally braced pile foundation cap, a pile row structure, and several sets of oblique supports supported between the diagonally braced pile foundation cap and the pile row structure; the diagonally braced pile foundation cap It includes a support platform 2 directly below the structural wall 1 and a support pile 3 supported on the bottom of the support platform 2. The pile row structure includes a pile row 4, a crown beam 5 arranged on the top surface of the pile row 4, and a pile row arranged in the middle of the pile toward the Waist beam 6 on one side of the foundation pit, each group of oblique supports includes a steel diagonal brace 17 arranged between crown beam 5 and support platform 2 .

Each group of oblique supports also includes the steel diagonal brace 2 8 located between the waist beam 6 and the support platform 2, the steel diagonal brace 1 7 and the steel diagonal brace 2 8 all pass through the structural wall 1, and are composed of several The steel pipe sections are formed by splicing flanges 9 together.

The top surface of the support platform is a plane, and the plane is provided with an inwardly recessed receiving groove 11 with a triangular cross section. The support surface 112 of the back slope and the surface 111 of the facing slope are provided with a support embedded steel plate 1, and the end of the steel diagonal support 17 is provided with an active head 17, and the end of the active head 17 passes through the embedded steel plate 1 of the support. Bolt on.

The end face of the supporting platform 2 facing the pile row structure is an inclined plane 14 perpendicular to the steel diagonal brace 2 8, the end of the steel diagonal brace 2 8 is provided with an active joint 2 15, and the inclined plane 14 is provided with a support pre-embedded steel plate 2 13, and the active joint Two 15 and the support pre-embedded steel plate two 13 are fixed by bolts; the steel diagonal brace one 7 and steel diagonal brace two 8 of each group of oblique supports are located on the same vertical plane; the foundation pit row pile support system also includes For supporting the central support lattice column 16 of the steel diagonal brace 1 7 and the steel diagonal brace 2 8, the central support lattice column 16 includes an upper steel column and a lower column pile, and the lower column pile is a reinforced concrete bored cast-in-place pile; the steel diagonal brace One 7 is welded and fixed towards the end of the crown beam 5 and the embedded steel plate fixed on the crown beam 5, and the end of the steel diagonal brace 8 is welded and fixed with the embedded steel plate fixed on the waist beam 6 towards the waist beam 6. Steel diagonal brace 1 7 and steel diagonal brace 2 8 are welded with a ring of water-proof steel plates where they pass through the structural side wall of structural wall 1, and the bottom plate of structural wall 1 is for steel diagonal brace 1 7 and steel diagonal brace 2 8 to pass through The part is equipped with a long post-casting belt.

A construction method for a foundation pit row pile support system is characterized in that it comprises the following steps:

Step 1. Construction of the pile row structure: clear the large area of earthwork, calculate the allowable excavation depth of the foundation pit and carry out the first excavation of the earthwork, and carry out the construction of the pile row structure. After the pile row 4 strength reaches more than 80% of the design strength, proceed The top of the pile is chiseled out, and the steel bar of the crown beam is bound after the reinforcement is planted. The pre-embedded steel plate used to fix the steel diagonal brace 17 is welded on the crown beam steel bar. The angle of the pre-embedded steel plate is based on the foundation elevation of the steel diagonal The distance between the cap of the inclined pile foundation and the row of piles 4 is checked and determined;

Step 2. Construction of the inclined braced pile foundation cap and steel diagonal brace 1 7: Excavate the earthwork at 2 places of the support platform to the design elevation, and carry out the construction of the diagonal braced pile foundation cap, the pre-embedded steel plate 1 of the support and the pre-embedded steel plate 2 of the support After construction, the steel diagonal brace 17 is lifted by the electric hoist on the lifting ring 10 located at the end of the steel diagonal brace 17 to be lifted in place. After being placed in place, the crane puts the hydraulic jack on the active head of the steel diagonal brace 17 17 At the constant pressure position, prestress is applied according to the design requirements, and a circle of water-stop steel plates is welded at the part where the steel diagonal brace 1 7 pre-passes through the structural wall 1 structural side wall;

Step 3. Construction of the waist beam 6: After the construction of the steel diagonal brace 1 7, the second earthwork excavation is carried out. The top of the earthwork is excavated to the position below the waist beam, and then sloped to the position of the slope 14 of the steel diagonal brace 2 8, and reserved At the earthwork boundary, carry out the construction of the waist beam 6 at the same time, dig out the steel bars and plant the bars at the row of piles 4, then bind the waist beam steel bars, and weld and fix the pre-embedded steel plates used to fix the steel diagonal brace 28. The angle of the pre-embedded steel plates is according to The foundation elevation of steel diagonal brace No. 2 8 and the height of waist beam 6 and the distance between the diagonal brace pile foundation cap and pile row 4 are checked and determined;

Step 4, construction center supporting lattice column 16 and steel diagonal brace 2 8: construction center supporting lattice column 16, and constructing steel diagonal brace 2 8 according to the steps of constructing steel diagonal brace 1;

Step 5. Construction of the structural wall 1: Excavate the remaining earthwork and carry out the construction of the structural wall 1. The first steel diagonal brace 7 and the second steel diagonal brace 8 are in contact with the bottom plate of the structural wall 1 to set up a long post-casting belt , in the specific construction, the oblique support required for each foundation pit is usually located on the same straight line, and a long post-casting belt can be set at the bottom plate of the structural wall 1, and in the process of pouring the side wall of the structural wall 1 , instead of reserving openings for steel brace 1 7 and steel brace 2 8, direct full-length pouring;

Step 6. Removal of oblique supports and waterproof treatment of structural wall 1: Loosen the bolts at the fixed parts of the oblique supports and the oblique brace pile caps to remove them, and cut and remove the parts connected with the crown beam 5 and the waist beam 6. Support and structure wall 1. The oblique support is cut at the node of the structural side wall, and a circle of water-stop steel plates is welded in the oblique support left on the structural side wall, and then waterproof concrete is poured. So far, it is a foundation pit row pile support system The construction method construction is completed.

Next, the utility model construction method is further described:

When the design requires low support bearing capacity, only choose the combination of steel diagonal brace 1 connected with the crown beam, without the construction of steel diagonal brace 2, which can meet the support requirements of the foundation pit. When the design requires a relatively high support bearing capacity When the safety requirements are high, choose the combined support form of steel diagonal brace 1 7 and steel diagonal brace 2 8.

Because the length of the first steel diagonal brace 7 and the second steel diagonal brace 8 is too long, the central support lattice column 10 provides a vertical support for the two diagonal braces at a position close to the center point of the steel diagonal brace, so the first steel diagonal brace 7 and the steel diagonal brace The second brace 8 needs to be on the same axis as the central support lattice column 16 in the vertical direction to ensure that the central support lattice column 16 can support the steel diagonal brace 1 7 and the steel diagonal brace 2 8 at the same time.

The suitable range of setting post-casting belts at 2 places of the steel diagonal brace-7 support platform is: the foundation pits requiring diagonal braces on each side are on the same straight line or several diagonal supports are on the same straight line, so that it can be set here. The post-cast strip is extended to the bottom plate within the support range, and a post-cast strip near the originally designed diagonal support can be changed to this place through design changes.

The steel diagonal brace is lifted into place by the electric hoist through the pre-embedded lifting ring. After being put in place, the crane puts the hydraulic jack into the pressing position of the active end, and applies prestress step by step according to the design requirements. The form of the flexible head needs to be used after the design is approved. Regarding the waterproof treatment at the second support of the steel diagonal brace, a circle of waterproof steel plates should be welded around the steel pipes of the diagonal braces, and waterproof materials such as coiled materials should be rolled from the cushion to the waterproof steel plates. Above, the waterproof treatment of steel diagonal brace 1 and steel diagonal brace 2 at the joints of the outer wall needs to weld a ring of waterproof steel plates inside after the steel pipe is cut, and then pour waterproof concrete.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection of the utility model.

Claims (8)

1. A pile row support system for a foundation pit is characterized in that: comprise a slanted pile foundation cap, a pile row structure, and several groups of oblique supports supported between the slanted pile foundation cap and the pile row structure; The diagonally braced pile foundation cap includes a supporting platform (2) directly below the structural wall (1) and supporting piles (3) supported on the bottom of the supporting platform (2), and the pile row structure includes a row of piles (4 ), the crown beam (5) arranged on the top surface of the row of piles (4) and the waist beam (6) arranged in the middle of the row of piles facing the side of the foundation pit, each group of diagonal supports includes the crown beam (5) Steel diagonal brace one (7) between the support platform (2). 2. A foundation pit row pile support system according to claim 1, characterized in that: each group of said oblique support also includes said support between the waist beam (6) and the support platform (2) The second steel diagonal brace (8), the first steel diagonal brace (7) and the second steel diagonal brace (8) pass through the structural wall (1), and are spliced by several steel pipe sections through flanges (9). to make. 3. A foundation pit row pile support system according to claim 1, characterized in that: the top surface of the support platform (2) is a plane, and the plane is provided with an inwardly recessed, triangular-shaped socket Groove (11), the internal plane of the receiving groove (11) includes a front diagonal bracing surface (111) perpendicular to the steel diagonal brace one (7) and a back diagonal brace surface (112) parallel to the steel diagonal brace one (7) , the support surface (111) is provided with a support pre-embedded steel plate 1, and the end of the steel diagonal brace 1 (7) is provided with a joint head 1 (17), and the end of the joint head 1 (17) It is fixed with the pre-embedded steel plate of the support by bolts. 4. A foundation pit row pile support system according to claim 1, characterized in that: the end face of the support platform (2) facing the pile row structure is an inclined plane (14) perpendicular to the steel diagonal brace two (8). ), the end of the steel brace 2 (8) is provided with a joint head 2 (15), and the inclined surface (14) is provided with a support pre-embedded steel plate 2 (13), and the joint head 2 (15) is connected with The support pre-embedded steel plate two (13) is fixed by bolts. 5. A foundation pit row pile support system according to claim 1, characterized in that: the steel diagonal brace one (7) and the steel diagonal brace two (8) of each group of diagonal supports are located in the same vertical direction on flat surface. 6. A foundation pit row pile support system as claimed in claim 5, characterized in that: said foundation pit row pile support system also includes steel brace one (7) and steel brace two ( 8) The central support lattice column (16), the central support lattice column (16) includes an upper steel column and a lower column pile, and the lower column pile is a reinforced concrete bored pile. 7. A foundation pit row pile support system according to claim 1, characterized in that: the steel diagonal brace one (7) faces the end of the crown beam (5) and is fixed on the crown beam (5) The pre-embedded steel plate is welded and fixed, and the end of the steel diagonal brace 2 (8) facing the waist beam (6) is welded and fixed to the embedded steel plate fixed on the waist beam (6). 8. A foundation pit row pile support system according to claim 1, characterized in that: the first steel diagonal brace (7) and the second steel diagonal brace (8) pass through the structural side of the structural wall (1) All parts of the wall are welded with a ring of water-stop steel plates, and the bottom plate of the structural wall (1) is provided with a long post-casting strip at the part where the first steel diagonal brace (7) and the second steel diagonal brace (8) pass through.