Deep foundation pit supporting structure

Abstract

The utility model provides a deep foundation pit supporting structure, which relates to the technical field of foundation pit supporting and comprises an external Larsen steel sheet pile and a steel enclosing purlin positioned on the inner side of the Larsen steel sheet pile, and the inner side of the steel enclosing purlin is connected with a steel supporting piece through a steel cushion box; a plurality of layers of steel enclosing purlins are horizontally arranged, each layer of steel enclosing purlins is connected with a layer of steel supporting pieces, four sets of steel supporting pieces are arranged on each layer of steel enclosing purlins, and a set of steel supporting pieces is connected between the steel enclosing purlins on the inner sides of every two adjacent Larsen steel sheet piles. Each set of steel supporting pieces comprises at least two steel supporting pieces, each set of steel supporting pieces comprises a long support and a plurality of short supports, and the long supports and the short supports of each set of steel supporting pieces are arranged in parallel. The utility model has the beneficial effects of reasonable design, simple structure, safety and reliability, and can provide reliable support for different soil layers, improve the supporting effect and reduce the construction difficulty and cost.

Description

Technical Field

[0001] The utility model relates to the technical field of foundation pit support, in particular to a deep foundation pit support structure. Background Art

[0002] In construction projects, deep foundation pit support is an important measure to ensure project safety. Currently, common deep foundation pit support technologies include deep mixing, pile support, underground continuous wall, etc. However, these technologies have certain limitations and shortcomings, such as high construction difficulty, high cost, and unsatisfactory support effect. Therefore, a new deep foundation pit support structure and construction method are needed to improve the support effect and reduce the construction difficulty and cost.

[0003] At present, there are many foundation pit support systems, especially those that support the soil outside the foundation pit vertically. During the excavation process, in order to ensure the safety of the excavation construction and the surrounding structures of the foundation pit, the side walls of the foundation pit need to be supported and reinforced. In the actual construction environment, the support system usually has to pass through multiple soil layers, such as: miscellaneous fill layer, loess-like silty clay layer, silty clay, etc. The mechanical and physical properties of each soil layer are different. For the foundation pit support system, there may be large differences in the forces at various parts of the vertical direction, resulting in a large reliability risk for the support system.

[0004] How to solve the above technical problems is the subject faced by the present utility model. Utility Model Content

[0005] In order to solve the deficiencies of the prior art, the utility model provides a deep foundation pit supporting structure with reasonable design, simple structure, safety and reliability, which can provide reliable support for different soil layers, improve the supporting effect, and reduce the construction difficulty and cost.

[0006] The technical solution adopted by the utility model to solve the technical problem is as follows: the utility model provides a deep foundation pit support structure, including an external Larsen steel sheet pile and a steel purlin located inside the Larsen steel sheet pile, wherein the inner side of the steel purlin is connected with a steel support member through a steel cushion box;

[0007] The steel perimeter purlins are arranged horizontally in several layers, each layer of the steel perimeter purlins is connected to a layer of the steel support members, each layer of the steel support members is arranged in four groups, and a group of the steel support members is connected between the steel perimeter purlins on the inner sides of each two adjacent Larsen steel sheet piles;

[0008] Each group of the steel support members includes at least two steel support members, each group of the steel support members includes a long support and a plurality of short supports, and the long support and the short support of each group of the steel support members are arranged in parallel.

[0009] The steel cushion box is in the shape of a right triangle, and the hypotenuse is fixedly connected to the steel purlin;

[0010] One right-angled side of the steel cushion box connected to the short support is fixedly connected to the short support, and two right-angled sides of the steel cushion box connected to the long support are respectively fixedly connected to one of the long supports.

[0011] The steel support is columnar, and each of the steel support comprises a flexible head at both ends fixedly connected to the steel cushion box, and the two flexible heads are connected to a steel pipe intermediate section through a steel wedge-shaped cushion block;

[0012] The plurality of steel pipe intermediate sections of each steel support are connected via flanges.

[0013] A triangular support plate is fixedly connected between the bottom of each steel cushion box and the inner side of the Larsen steel sheet pile.

[0014] A corner reinforcement is provided at the connection point between each two adjacent steel purlins.

[0015] The Larsen steel sheet pile is 12m long.

[0016] Adjacent steel purlins are fixedly connected via web connecting plates and flange connecting plates;

[0017] The webs of two adjacent steel purlins are connected by welding through the web connecting plates affixed thereto, and the flanges of two adjacent steel purlins are connected by welding through the flange connecting plates affixed thereto.

[0018] The beneficial effects of the utility model are as follows: the scheme adopts the system of Larsen steel sheet piles and horizontal support support, and a plurality of steel sheet piles are connected to form a steel sheet pile wall supporting the side wall of the foundation pit, and an inner support component for providing support therefor in the horizontal direction is also arranged on the inner wall of the steel sheet pile wall, so that the reliability of the steel sheet pile wall supporting the side wall of the foundation pit is greatly improved, and even if the steel sheet pile passes through multiple soil layers, it can still provide reliable support, and through this system, the support effect can be effectively improved, and the construction difficulty and cost can be reduced;

[0019] The special horizontal support method of this scheme, including right-angled triangle steel pad boxes, support pipes of the same length and transfer reinforcements, can effectively improve the support effect.

[0020] The construction method of this scheme is simple and easy to implement, and can meet the deep foundation pit support needs of different depths and geological conditions;

[0021] The steel sheet piles in this solution can be reused, which is beneficial to saving resources and reducing project costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a top view of the utility model.

[0023] Figure 2 It is a schematic diagram of the main construction view of the utility model.

[0024] Figure 3 It is a top view of the connection between the steel purlin and the steel support member of the utility model.

[0025] Figure 4 This is a schematic diagram of the connection of the steel purlin of the utility model.

[0026] Among them, the accompanying drawings are marked as: 1. Larsen steel sheet pile; 2. Steel purlin; 201. Triangular support plate; 202. Web connecting plate; 203. Flange connecting plate; 3. Steel support member; 301. Flange; 303. Steel pipe intermediate section; 304. Steel wedge-shaped pad; 305. Active head; 4. Steel pad box; 5. Corner reinforcement; 6. Main structure; 7. Power transmission belt. DETAILED DESCRIPTION

[0027] The technical features of this solution can be clearly explained. The solution is described below through a specific implementation method.

[0028] See also Figures 1 to 4 As shown, this embodiment is a deep foundation pit support structure, including an external Larsen steel sheet pile 1 and a steel purlin 2 located inside the Larsen steel sheet pile 1, and a steel support member 3 is connected to the inside of the steel purlin 2 through a steel cushion box 4;

[0029] The steel purlins 2 are arranged horizontally in several layers, each layer of the steel purlins 2 is connected to a layer of steel support members 3, each layer of the steel support members 3 is provided with four groups, and a group of steel support members 3 is connected between the steel purlins 2 on the inner sides of each two adjacent Larsen steel sheet piles 1;

[0030] Each group of steel support members 3 includes at least two steel support members 3 , each group of steel support members 3 includes a long support and a plurality of short supports, and the long support and the short support of each group of steel support members 3 are arranged in parallel.

[0031] The steel cushion box 4 is in the shape of a right triangle, and the hypotenuse is fixedly connected to the steel purlin 2;

[0032] One right-angled side of the steel cushion box 4 connected to the short support is fixedly connected to the short support, and two right-angled sides of the steel cushion box 4 connected to the long support are respectively fixedly connected to one long support.

[0033] The steel support member 3 is columnar, and each of the steel support members 3 includes a flexible head 305 at both ends fixedly connected to the steel cushion box 4, and the two flexible heads 305 are connected to a steel pipe intermediate section 303 through a steel wedge-shaped cushion block 304;

[0034] The several steel pipe intermediate sections 303 of each steel support 3 are connected by flanges 301 .

[0035] A triangular support plate 201 is fixedly connected between the bottom of each steel pad box 4 and the inner side of the Larsen steel sheet pile 1 .

[0036] A corner reinforcement 5 is provided at the connection between every two adjacent steel purlins 2 .

[0037] Larsen steel sheet pile is 12m long.

[0038] Adjacent steel purlins 2 are fixedly connected via web connecting plates 202 and flange connecting plates 203;

[0039] The webs of two adjacent steel purlins 2 are connected by welding via a web connecting plate 202 attached thereto, and the flanges of two adjacent steel purlins 2 are connected by welding via a flange connecting plate 203 attached thereto.

[0040] When the utility model is actually used:

[0041] 1. Larsen Steel Sheet Pile 1 Construction

[0042] 1. Measurement and setting out: accurately set out the center line of Larsen steel sheet pile 1 according to the construction drawings and control piles;

[0043] 2. Inspection of Larsen steel sheet piles 1: Larsen IV steel sheet piles are selected for construction. Larsen steel sheet piles 1 with a pile length of 12m are used for bending, shaping, correction, cutting and welding. The model, specification and quantity of Larsen steel sheet piles 1 required for construction are sorted out. 90° corner piles are used at the corners. The locking mouth is checked. The locking mouth of each Larsen steel sheet pile 1 is evenly coated with mixed oil. The volume ratio is butter: dry bentonite: dry sawdust = 5:5:3;

[0044] 3. Lifting and stacking of Larsen steel sheet piles 2;

[0045] 4. Larsen steel sheet pile 2 is driven in: the control points of each section are introduced through the pile intersection points of the design unit, and they are effectively protected after verification. The plane control points are set at the boundary of the foundation pit, and the measurement is carried out. After the buried elevation of Larsen steel sheet pile 1 is clarified, the guide steel of Larsen steel sheet pile 1 is driven in. The guide piles are steel sheet piles, and the steel is set on the triangular bracket welded on the steel sheet piles. The steel is used to ensure that the driven steel sheet piles are in a straight line. The guide beam is H-shaped steel, and the net distance between the guide beams is the width of the sheet pile. The Larsen steel sheet pile 1 is hoisted to the pile position by a pile driver for pile driving. When driving the pile, the lock buckle of the last pile is aligned with the lock buckle of the previous pile. After they are engaged with each other, the vibrating hammer is turned on and hammered lightly to make the steel sheet pile enter the soil 1 to 2m. During the pile driving process, the verticality of the pile is observed while driving. The verticality can be observed by using two theodolites or plumb bobs in two directions. According to the requirements of the steel sheet pile support project for verticality and elevation, combined with the on-site soil conditions and progress requirements, the single driving method and the screen driving method can be used in combination;

[0046] 5. Pile extraction: After the foundation pit is backfilled, the steel sheet piles must be removed for reuse.

[0047] 2. Support system construction

[0048] 1. Processing and manufacturing of the internal support system: The steel purlin 2 adopts a double-type purlin, and the triangular support plate 201, Larsen steel sheet pile 1, steel purlin 2, and steel support 3 are all connected by welding;

[0049] The steel support 3 is constructed with a steel pipe intermediate section 303 with a diameter of 609 mm. A set of steel support 3 is arranged between the steel purlins 2 of each adjacent Larsen steel sheet pile 1 on each layer. The standard length of each section is customized according to the size of the foundation pit, and steel wedge-shaped pads 304 of different sizes are prepared to ensure that the steel support 3 can make fine adjustments;

[0050] 2. Installation of the support system: After the foundation pit is excavated to an elevation of 50cm below the design centerline of the support, the axis and elevation of the steel purlin 2 are accurately determined according to the control axis and level point of the entire structure; the steel purlin 2 is hoisted by a crane. After installation, the actual net distance between the two ends of the support is measured. The connection of the steel purlin 2 is welded by flange connecting plates and web connecting plates; the steel support 3 is hoisted on site by a crane, using two-point hoisting, and the hoisting point is about 0.2L away from the end. After the steel support 3 is hoisted in place, it is welded and connected; the qualified support is hoisted in place by a crane, and the support hoisting adopts two-point hoisting. During the hoisting process, the support must be kept stable, without collision and deformation.

[0051] After the steel support 3 is hoisted in place, the steel support 3 is adjusted to the designed position with manual assistance and then the steel support 3 is fixed;

[0052] 3. Removal of the support system: After pouring the raft slab, the force transfer belt 7 is constructed. After the construction of the force transfer belt 7 is completed, the lower support is removed. The force transfer belt 7 uses C20 plain concrete; after the lower support is removed, the main structure 6 is constructed. After the main structure 6 is constructed, the fertilizer tank is backfilled. After the fertilizer tank is backfilled, the upper steel support is directly removed.

[0053] Technical features not described in the present invention can be achieved through or by adopting existing technologies, and will not be elaborated here. Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the scope of protection of the present invention.

Claims

1. A deep foundation pit support structure, characterized in that: It comprises an external Larsen steel sheet pile (1) and a steel purlin (2) located inside the Larsen steel sheet pile (1), wherein the inside of the steel purlin (2) is connected to a steel support member (3) via a steel cushion box (4); The steel purlins (2) are arranged horizontally in a plurality of layers, each layer of the steel purlins (2) is connected to a layer of the steel support members (3), each layer of the steel support members (3) is provided with four groups, and a group of the steel support members (3) is connected between the steel purlins (2) on the inner sides of each two adjacent Larsen steel sheet piles (1); Each group of the steel support members (3) comprises at least two steel support members (3), each group of the steel support members (3) comprises a long support and a plurality of short supports, and the long supports and short supports of each group of the steel support members (3) are arranged in parallel.

2. The deep foundation pit support structure according to claim 1 is characterized in that: The steel cushion box (4) is in the shape of a right triangle, and the hypotenuse is fixedly connected to the steel purlin (2); One right-angled side of the steel cushion box (4) connected to the short support is fixedly connected to the short support, and two right-angled sides of the steel cushion box (4) connected to the long support are respectively fixedly connected to one of the long supports.

3. The deep foundation pit support structure according to claim 1, characterized in that: The steel support member (3) is columnar, and each of the steel support members (3) comprises a flexible head (305) at both ends fixedly connected to the steel cushion box (4), and the two flexible heads (305) are connected to a steel pipe intermediate section (303) via a steel wedge-shaped cushion block (304); The plurality of steel pipe intermediate sections (303) of each steel support member (3) are connected via flanges (301).

4. The deep foundation pit support structure according to claim 1, characterized in that: A triangular support plate (201) is fixedly connected between the bottom of each steel cushion box (4) and the inner side of the Larsen steel sheet pile (1).

5. The deep foundation pit supporting structure according to claim 1, characterized in that: A corner reinforcement member (5) is provided at the connection point between each two adjacent steel purlins (2).

6. The deep foundation pit supporting structure according to claim 1, characterized in that: The Larsen steel sheet pile (1) has a length of 12 m.

7. The deep foundation pit supporting structure according to claim 1, characterized in that: Adjacent steel purlins (2) are fixedly connected via a web connecting plate (202) and a flange connecting plate (203); The webs of two adjacent steel purlins (2) are connected by welding via the web connecting plates (202) affixed thereto, and the flanges of two adjacent steel purlins (2) are connected by welding via the flange connecting plates (203) affixed thereto.

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