Inner supporting lattice stand column pile

Abstract

The utility model relates to the field of inner supporting foundation pit supporting structures, in particular to an inner supporting lattice stand column pile which comprises a prestressed pipe pile and a reinforcement cage, the prestressed pipe pile is pressed into the ground, the reinforcement cage is inserted into the top of the prestressed pipe pile, and the reinforcement cage and a reinforcement framework of a supporting beam are connected into a whole. The prestressed pipe piles and the supporting beams are connected into a whole through concrete poured into the reinforcement cage. According to the embodiment of the utility model, the prestressed pipe piles are used as the inner support lattice stand column piles, and the prestressed pipe piles and the support beams are combined into a whole to form the foundation pit inner support supporting structure, so that the problems that the shearing strength and the bending strength of the traditional steel lattice stand column are low, rotary excavating equipment is required to be introduced when the steel lattice stand column is built in the foundation pit, and the construction cost is low are solved. And the construction cost and the construction period are increased.

Description

Technical Field

[0001] This utility model relates to the field of internal support foundation pit support structure, specifically to an internal support grid column pile. Background Technology

[0002] The relevant technology of the internally supported lattice column pile disclosed in this utility model is disclosed in: CN105239594B Prestressed pipe pile column.

[0003] In the internal support structure of the foundation pit, the traditional steel lattice columns have low shear and bending strength, making it difficult to cope with the pressure of soft soil layers and the problems of soil erosion and quicksand caused by high groundwater levels. Constructing steel lattice columns inside the foundation pit requires the introduction of rotary drilling equipment, which increases construction costs and time.

[0004] Therefore, there is a need for lattice columns with high shear and bending strength and that can be constructed quickly. Utility Model Content

[0005] The purpose of this utility model is to provide an internally supported lattice column pile to solve the technical problems of the low shear and bending strength of traditional steel lattice columns, and the need to introduce rotary drilling equipment to construct steel lattice columns inside the foundation pit, which increases construction costs and time.

[0006] To solve the above-mentioned technical problems, this utility model specifically provides the following technical solution:

[0007] An internally supported lattice column pile includes a prestressed pipe pile and a reinforcing cage. The prestressed pipe pile is pressed into the ground, and the reinforcing cage is inserted into the top of the prestressed pipe pile. The reinforcing cage is connected to the reinforcing steel skeleton of a support beam as a whole. The prestressed pipe pile and the support beam are connected as a whole by concrete poured into the reinforcing cage.

[0008] Furthermore, the bottom of the reinforcing cage is sealed by a steel plate, so that the height of the concrete poured into the prestressed pipe pile is equal to the height of the reinforcing cage.

[0009] Furthermore, the main reinforcing bars of the steel cage are bent outward horizontally, and the main reinforcing bars are connected to the steel reinforcement skeleton of the supporting beam as a whole.

[0010] Furthermore, the two prestressed pipe piles are connected by welding, and a first clamp is installed on the outside of the prestressed pipe pile to reinforce the weld joint.

[0011] Furthermore, the prestressed pipe pile is equipped with a second clamp, and an embedded steel plate is welded to the top of the second clamp. The anchor bars of the embedded steel plate are connected to the steel reinforcement skeleton of the support beam as a whole. The prestressed pipe pile and the support beam are connected as a whole by pouring concrete onto the second clamp and the periphery of the embedded steel plate.

[0012] In another embodiment of this application, a steel pipe pile is provided between the two prestressed pipe piles. The steel pipe pile and the prestressed pipe pile are connected by welding. The total length of each prestressed pipe pile and the steel pipe pile is equal to the story height between the two adjacent supporting beams.

[0013] Furthermore, the top of the steel pipe pile is welded with an embedded steel plate surrounding the steel pipe pile, and the anchor bars of the embedded steel plate are connected to the steel reinforcement skeleton of the support beam as a whole. The prestressed pipe pile and the support beam are connected as a whole by concrete poured onto the steel pipe pile and the periphery of the embedded steel plate.

[0014] Compared with the prior art, this application has the following advantages:

[0015] This invention provides an internally supported lattice column pile, which uses prestressed pipe piles as the internally supported lattice column piles. The prestressed pipe piles are combined with the support beams to form an internal support structure for the foundation pit. This solves the technical problems of the low shear and bending strength of traditional steel lattice columns and the need to introduce rotary drilling equipment to construct steel lattice columns inside the foundation pit, which increases construction costs and time. Attached Figure Description

[0016] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0017] Figure 1 This is a front view of the welded structure of two prestressed pipe piles according to the first embodiment of this utility model;

[0018] Figure 2 This is a top view of the welded structure of two prestressed pipe piles according to the first embodiment of this utility model;

[0019] Figure 3 This is a cross-sectional view of the connection structure between the pile top and the support beam of the prestressed pipe pile according to the first embodiment of this utility model.

[0020] Figure 4This is a schematic diagram showing the location of the connection structure between the pile top and the support beam of the prestressed pipe pile in the foundation pit, according to the first embodiment of this utility model.

[0021] Figure 5 This is a schematic diagram showing the location of the connection structure of the prestressed pipe pile, support beam and raft slab inside the foundation pit in the first embodiment of this utility model.

[0022] Figure 6 This is a cross-sectional view of the connection structure between the prestressed pipe pile and the raft slab in the first embodiment of this utility model.

[0023] Figure 7 for Figure 6 A cross-sectional view along the AA direction;

[0024] Figure 8 This is a cross-sectional view of the connection structure between the steel pipe pile and the support beam according to the second embodiment of this utility model;

[0025] Figure 9 This is a schematic diagram showing the location of the connection structure of the prestressed pipe pile, steel pipe pile, support beam and raft slab inside the foundation pit in the second embodiment of this utility model.

[0026] The labels in the diagram represent the following:

[0027] 1-Foundation pit; 11-Raft foundation; 2-Support beam; 3-Column pile; 31-Prestressed pipe pile; 32-Weld; 33-First clamp; 34-Second clamp; 35-Bolt; 36-Steel pipe pile; 37-Pin; 38-Pipe plug; 4-Reinforcing cage; 41-Main reinforcement; 42-Steel plate; 5-Embedded steel plate; 51-Anchor bar; 6-Rubber waterstop; 7-Waterstop steel plate. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] (First Embodiment)

[0030] The following describes a construction method for internally supported lattice column piles, including the following steps:

[0031] Step 1: Construction Preparation: Conduct a detailed site survey to understand the geological conditions and groundwater level. Arrange the construction site according to the design requirements, determine the pile positions and mark them. Prepare construction materials such as prestressed pipe piles 31, steel cages 4, concrete, embedded steel plates 5, rubber waterstops 6, first clamps 33, and second clamps 34, and ensure that the quality of the materials meets the requirements.

[0032] Step 2: Install prestressed pipe pile 31: Lift the prestressed pipe pile 31 with specifications of HPC-600-C-130, and align the pile tip vertically with the center of the pile position. First, use the weight of the pile hammer to insert the prestressed pipe pile 31 into the ground 30cm to 50cm, then make the prestressed pipe pile 31 vertical and stable, and then use a static pressure pile driver to press the prestressed pipe pile 31 into the ground.

[0033] Step 3, Continuing the prestressed concrete pipe pile 31: Combining Figure 1 , Figure 2 When the length of the prestressed pipe pile 31 is insufficient, the two sections of prestressed pipe pile 31 are connected by welding. The height of the weld 32 is not less than 10mm. The outside of the weld 32 is reinforced with a first clamp 33. The height of the first clamp 33 is not less than 500mm. The first clamp 33 is installed with M30 high-strength bolts 35 of grade 10.9. The preload of each bolt 35 is 355KN to ensure the strength and sealing of the joint between the two sections of prestressed pipe pile 31.

[0034] Step 4: Connect the top of the prestressed concrete pipe pile 31 to the supporting beam 2: Combine Figure 3 A precast steel cage 4 with a diameter of 300mm is inserted into the top of the pile. The bottom of the steel cage 4 is closed by a steel plate 42 with a diameter of 310mm. The main reinforcement 41 of the steel cage 4 has a length of 3800mm. The top of the main reinforcement 41 of the steel cage 4 is bent outward so that the main reinforcement 41 of the steel cage 4 extends horizontally outward by 800mm. The horizontally extended main reinforcement 41 of the steel cage 4 is connected to the steel skeleton of the support beam 2 as a whole. The two are fixed by binding or welding. Then, concrete is poured simultaneously inside the prestressed pipe pile 31 and inside the mold of the support beam 2. The concrete will fill the inside of the prestressed pipe pile 31 and the mold of the support beam 2.

[0035] Step 5: Excavating underground space: combining Figure 4 After the concrete has solidified, the prestressed pipe pile 31 and the support beam 2 are firmly connected to form an integral internal support structure. The concrete inserted into the prestressed pipe pile 31 and the steel cage 4 form a pin 37, which can prevent rainwater from entering the interior of the prestressed pipe pile 31.

[0036] Then, an excavator is used to excavate an underground space between the prestressed pipe pile 31 and the support beam 2. It should be noted that the earthwork excavation process should adopt the basin excavation technique, and the area within 1m around the prestressed pipe pile 31 should be protected to prevent the excavator from colliding with the prestressed pipe pile 31.

[0037] Step Six: Connecting Prestressed Pipe Piles 31 to Raft Slab 11: Combining Figure 5 A second clamp 34 is installed at the connection between the prestressed pipe pile 31 and the raft slab 11. The first clamp 33 and the second clamp 34 are of the same specifications. A 20mm thick rubber waterstop 6 is inserted between the second clamp 34 and the prestressed pipe pile 31. A 1000mm×1000mm embedded steel plate 5 is welded to the top of the second clamp 34. The center of the embedded steel plate 5 has a through hole for avoiding the pile body. The diameter of the through hole is greater than 600mm and less than 650mm. An anchor bar 51 with a diameter of 20mm and a length of 800mm is plugged and welded to the bottom of the embedded steel plate 5. The anchor bar 51 is connected to the steel reinforcement skeleton of the raft slab 11 as a whole. The two are fixed by binding or welding. Then, concrete is poured into the mold of the raft slab 11. After the concrete solidifies, the prestressed pipe pile 31, the second clamp 34, the rubber waterstop 6, the embedded steel plate 5 and the raft slab 11 are firmly connected as a whole.

[0038] Step 7: Remove support beam 2: Combine Figure 6 , Figure 7 According to the design requirements, the basement was constructed layer by layer from bottom to top, and the supporting beam 2 was removed. At the same time, the excess prestressed pipe piles 31 that were higher than the raft slab 11 were removed. Then, the cuts were trimmed and leveled. P8 impermeable fine stone concrete was filled into the interior of the prestressed pipe piles 31 to a height of 5 meters. Then, a water-stop steel plate 7 was welded to the top of the embedded steel plate 5 to seal the through hole in the center of the embedded steel plate 5. The water-stop steel plate 7 is a circular shape with a diameter of 650 mm. Finally, fine stone concrete was filled on top of the water-stop steel plate 7 to make the surface of the raft slab 11 flat. The concrete filled into the interior of the prestressed pipe piles 31 forms a pipe plug 38, which can prevent groundwater from leaving the interior of the prestressed pipe piles 31.

[0039] When the internal support structure of the foundation pit has two or more layers of support beams 2, step four also includes connecting the pile body of the prestressed pipe pile 31 with the support beam 2: combining Figure 8 A second clamp 34 is installed at the connection between the pile body and the support beam 2. An embedded steel plate 5 is welded to the top of the second clamp 34. The anchor bar 51 of the embedded steel plate 5 is connected to the steel reinforcement skeleton of the support beam 2 as a whole. The two are fixed by binding or welding. Then, concrete is poured into the mold of the support beam 2. After the concrete solidifies, the pile body, the second clamp 34, the embedded steel plate 5 and the support beam 2 are firmly connected as a whole.

[0040] (Second Embodiment)

[0041] Compared to the technique of using a precast steel cage 4 to connect the prestressed pipe pile 31 and the support beam 2 into one unit, the second clamp 34 has a weaker bond strength with the prestressed pipe pile 31. When the depth of the foundation pit 1 is large and the weight of the support beam 2 is heavy, the second clamp 34 is at risk of sliding down from the pile body of the prestressed pipe pile 31.

[0042] To solve this problem, one possible approach is to directly weld the pre-embedded steel plate 5 to the pile body of the prestressed pipe pile 31 instead of using the second clamp 34, thereby improving the bonding strength between the prestressed pipe pile 31 and the support beam 2.

[0043] Specifically, except for the first and second prestressed pipe piles 31 which are 15 meters long, the other prestressed pipe piles 31 are 3 to 6 meters long. Each prestressed pipe pile 31 is connected to the others by steel pipe piles 36. The total length of each prestressed pipe pile 31 and each steel pipe pile 36 is equal to the story height of the supporting beam 2. The outer diameter of the steel pipe pile 36 is the same as the outer diameter of the prestressed pipe pile 31, which is 600 mm. The specific length of the steel pipe pile 36 is less than or equal to the thickness of the supporting beam 2. The embedded steel plate 5 is welded to the steel pipe pile 36.

[0044] The specific steps for connecting the support beam 2 to the steel pipe pile 36 are as follows: the embedded steel plate 5 is welded around the steel pipe pile 36, the anchor bars 51 of the embedded steel plate 5 and the steel reinforcement skeleton of the support beam 2 are connected by binding or welding, and then concrete is poured into the mold of the support beam 2. After the concrete solidifies, the steel pipe pile 36, the embedded steel plate 5 and the support beam 2 are combined into one.

[0045] In addition, the second clamp 34 can be omitted, and the pre-embedded steel plate 5 can be directly welded to the pile body of the prestressed pipe pile 31, thereby improving the bonding strength between the prestressed pipe pile 31 and the raft slab 11.

[0046] The specific steps for connecting the raft foundation 11 to the steel pipe pile 36 are as follows: the embedded steel plate 5 is welded around the steel pipe pile 36, the anchor bars 51 of the embedded steel plate 5 and the steel reinforcement skeleton of the raft foundation 11 are connected by binding or welding, and then concrete is poured into the mold of the supporting beam 2. After the concrete solidifies, the steel pipe pile 36, the embedded steel plate 5 and the raft foundation 11 are integrated into one, and the rubber waterstop 6 is not required.

[0047] It should be emphasized that the specifications of the prestressed pipe pile 31, the dimensions of the steel pipe pile 36, the dimensions of the support beam 2, and the dimensions of the embedded steel plate 5 in the first and second embodiments are only examples, and their specific dimensions should be designed and selected according to the site conditions.

[0048] The above embodiments are merely exemplary embodiments of this utility model and are not intended to limit this utility model. The scope of protection of this utility model is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this utility model within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of this utility model.

Claims

1. A type of internally supported lattice column pile, characterized in that, It includes a prestressed pipe pile (31) and a reinforcing cage (4). The prestressed pipe pile (31) is pressed into the ground, and the reinforcing cage (4) is inserted into the top of the prestressed pipe pile (31). The reinforcing cage (4) is connected to the reinforcing skeleton of the supporting beam (2) as a whole. The prestressed pipe pile (31) and the supporting beam (2) are connected as a whole by concrete poured into the reinforcing cage (4).

2. The internally supported lattice column pile according to claim 1, characterized in that, The bottom of the steel cage (4) is closed by a steel plate (42), so that the height of the concrete poured into the prestressed pipe pile (31) is equal to the height of the steel cage (4).

3. The internally supported lattice column pile according to claim 1, characterized in that, The main reinforcement bars (41) of the steel cage (4) are bent outward horizontally, and the main reinforcement bars (41) are connected to the steel reinforcement skeleton of the support beam (2) as a whole.

4. The internally supported lattice column pile according to claim 1, characterized in that, The two prestressed pipe piles (31) are connected by welding. A first clamp (33) is installed on the outside of the prestressed pipe pile (31) to reinforce the weld joint.

5. The internally supported lattice column pile according to claim 4, characterized in that, The prestressed pipe pile (31) is equipped with a second clamp (34) on its pile body. The top of the second clamp (34) is welded with an embedded steel plate (5) surrounding the second clamp (34). The anchor bar (51) of the embedded steel plate (5) is connected to the steel reinforcement skeleton of the support beam (2) as a whole. The prestressed pipe pile (31) and the support beam (2) are connected as a whole by pouring concrete around the second clamp (34) and the embedded steel plate (5).

6. The internally supported lattice column pile according to claim 1, characterized in that, A steel pipe pile (36) is set between the two prestressed pipe piles (31). The steel pipe pile (36) and the prestressed pipe pile (31) are connected by welding. The total length of each prestressed pipe pile (31) and the steel pipe pile (36) is equal to the height between the adjacent two layers of the support beam (2).

7. The internally supported lattice column pile according to claim 6, characterized in that, The top of the steel pipe pile (36) is welded with an embedded steel plate (5) surrounding the steel pipe pile (36). The anchor bar (51) of the embedded steel plate (5) is connected to the steel reinforcement skeleton of the support beam (2) as a whole. The prestressed pipe pile (31) and the support beam (2) are connected as a whole by concrete poured around the steel pipe pile (36) and the embedded steel plate (5).

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