Adjustable pre-opening steel sheet pile structure

Abstract

The utility model relates to the technical field of deep foundation pit supporting, in particular to an adjustable pre-opening steel sheet pile structure which comprises a steel sheet pile, a steel baffle and an anchor cable assembly. The cross section of the steel sheet pile is U-shaped, two openings are formed in the steel sheet pile and vertically driven into a stratum at the bottom of a foundation pit, two anchor cable assemblies are arranged for foundation pit supporting, clamping grooves are formed in the outer sides of the openings, the tops of the clamping grooves are open, and the two sides and the bottom of the clamping grooves are closed. The steel baffles are strip-shaped steel plates and can be inserted into the clamping grooves from the upper portions to seal the openings. One end of the anchor cable assembly is installed in a soil layer on the outer side of the foundation pit, and the other end of the anchor cable assembly penetrates out of a gap between the two adjacent steel baffles at the opening and is locked through an anchorage device. The strip-shaped opening and the clamping groove are formed in the steel sheet pile, the anchor cable drilling position can be adjusted, after the anchor cable is constructed, the pre-opening can be closed through the clamping groove and the steel baffle, the strength and rigidity of the steel sheet pile are ensured, the anchor cable construction requirements under different conditions can be met, and the technical problem during anchor cable construction of the steel sheet pile can be solved.

Description

Technical Field

[0001] This utility model relates to the field of deep foundation pit support technology, and in particular to an adjustable pre-opened steel sheet pile structure. Background Technology

[0002] A deep foundation pit is an excavation exceeding 5 meters in depth, based on the foundation design location, base elevation, and foundation plan dimensions. During deep foundation pit excavation, support measures are required to ensure the stability of the pit's sidewalls. Commonly used deep foundation pit support measures include retaining piles, anchor cables, soil nailing walls, internal bracing, and diaphragm walls. Among these, U-shaped steel sheet piles are a type of recyclable deep foundation pit support pile that can be combined with prestressed anchor cables to form a pile-anchor support structure, and are widely used in the field of deep foundation pit support.

[0003] U-shaped sheet piles are a type of steel section with interlocking seams. Their cross-section is U-shaped, with a commonly used width of 400mm and a length of 9m. When used in combination with anchor cables, an opening needs to be made on the sheet pile surface at the anchor cable hole location to allow the anchor cable to be installed through the sheet pile within the soil layer, forming a pile-anchor support structure to jointly bear the soil pressure on the pit sidewall. Since the depth and location of the anchor cable hole are calculated based on the pit depth, soil conditions, and ground surcharge, the anchor cable hole location varies for each pit. The current practice is to make an on-site gas-cut opening on the sheet pile according to the designed anchor cable hole depth, and then install the anchor cable. After the pit is backfilled and the sheet pile is pulled out, the opening on the sheet pile is welded shut. Furthermore, since the diameter of the opening formed by gas cutting on the sheet pile is mostly small (50-80mm), if underground obstacles are encountered during the anchor cable drilling process, the anchor cable opening position cannot be adjusted vertically, requiring the sheet pile to be re-cut with gas. Sometimes, to avoid underground obstacles, the anchor drilling position needs to be adjusted multiple times, resulting in multiple small holes in the sheet pile. This construction process is not only complex and time-consuming, but the repeated gas cutting and welding on the sheet pile also seriously affects its strength and stiffness. Sheet piles must be scrapped after a certain number of uses. Therefore, researching a new type of sheet pile structure that facilitates anchor installation is of great significance. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model discloses an adjustable pre-opened steel sheet pile structure.

[0005] The specific technical solution is as follows:

[0006] An adjustable pre-opening steel sheet pile structure includes steel sheet piles, steel baffles, and anchor cable assemblies. The steel sheet piles have a U-shaped cross-section, with two free ends pointing inwards and a closed end pointing outwards, vertically driven into the stratum at the bottom of the foundation pit. Two openings are made on the closed end for installing two sets of anchor cable assemblies for foundation pit support. A slot is provided on the outside of the opening, with the top of the slot open and the sides and bottom closed. The steel baffle is a strip-shaped steel plate, consisting of multiple pieces, which can be inserted into the slot from the top to close the opening. One end of the anchor cable assembly is installed inside the soil layer outside the foundation pit, and the other end of the anchor cable assembly passes through the gap between two adjacent steel baffles at the opening and is locked with an anchor.

[0007] The anchor cable assembly includes an anchor cable hole, an anchor cable, a steel waist beam, a pad plate, a wedge, and an anchor. The anchor cable hole is opened inside the soil layer of the pit sidewall. The steel waist beam, pad plate, wedge, and anchor are installed outside the steel baffle. The steel waist beam includes two channel steels, which are welded parallel to each other outside the slot. The anchor cable is placed in the anchor cable hole and passes through the opening and the gap of the steel waist beam, then passes through the pad plate and the wedge in sequence, and is finally locked by the anchor. The position where the anchor cable passes through the opening is left above and below by multiple stacked steel baffles.

[0008] The opening is elongated, with a length of 600mm and a width of 60mm, and the width of the slot is greater than or equal to the width of the steel baffle.

[0009] The steel baffle is 100mm long and 75mm wide.

[0010] The two openings are respectively located 2m and 4m below the top of the sheet pile.

[0011] When constructing two anchor cables, both openings are used simultaneously; or when constructing one anchor cable, only one opening is used, and the other opening is sealed with a steel baffle.

[0012] Compared with the prior art, the present invention has the following beneficial technical effects:

[0013] This invention achieves adjustable anchor drilling positions by setting strip-shaped openings and slots on the sheet piles. After anchor installation, the pre-openings can be closed by the slots and steel baffles to ensure the strength and rigidity of the sheet piles. This sheet pile structure can meet the anchor installation requirements under different conditions, offering convenient installation, adjustable anchor positions, and unaffected sheet pile support strength and rigidity.

[0014] This invention provides a wider range of options for selecting the anchor cable drilling opening position by pre-drilling strip holes on the U-shaped steel sheet pile, which meets the anchor cable opening position requirements of most deep foundation pits and avoids the drawback of gas cutting holes on the steel sheet pile before anchor cable construction.

[0015] This invention pre-drills elongated holes in U-shaped steel sheet piles. When anchor cable construction encounters obstacles and cannot proceed, the position of the anchor cable hole can be easily adjusted upwards or downwards by a certain distance, thereby avoiding underground obstacles. This eliminates the need for multiple drillings on the steel sheet piles, greatly improving construction efficiency and extending the service life of the steel sheet piles. Attached Figure Description

[0016] Figure 1 This is an elevation view of the steel sheet pile structure of this utility model;

[0017] Figure 2 This is a cross-sectional view of the strip opening in the steel sheet pile structure of this utility model;

[0018] Figure 3 This is a cross-sectional view of the strip opening after the steel sheet pile structure baffle of this utility model is installed;

[0019] Figure 4 This is a side view of the steel sheet pile anchor cable installation of this utility model.

[0020] Figure 5 This is a detailed drawing of the installation of anchor cables on steel sheet piles according to this utility model.

[0021] In the diagram, 1 is a sheet pile; 2 is an opening; 21 is a slot; 22 is a steel baffle; 3 is an anchor cable hole; 31 is an anchor cable; 32 is a steel girder; 33 is a pad; 34 is a wedge; and 35 is an anchor. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the accompanying drawings. Example

[0023] Figure 1 This is an elevation view of the steel sheet pile structure of this utility model. Figure 2 This is a cross-sectional view of the strip opening in the steel sheet pile structure of this utility model. Figure 3 This is a cross-sectional view of the strip opening after the steel sheet pile structure baffle of this utility model is installed. Figure 4 This is a side view of the steel sheet pile anchor cable installation according to this utility model. Figure 5The figure shows a detailed drawing of the installation of anchor cables on the sheet piles of this utility model: The adjustable pre-opened sheet pile structure of this utility model includes a sheet pile 1, a steel baffle 22, and an anchor cable assembly; the sheet pile 1 has a U-shaped cross-section, with two free ends pointing inward and a closed end pointing outward, vertically driven into the stratum at the bottom of the foundation pit. Two openings 2 are opened on the closed end for setting two sets of anchor cable assemblies for foundation pit support. The two openings 2 are respectively opened 2m and 4m below the top of the sheet pile 1. The two openings 2 are used simultaneously when constructing two anchor cables 31; the openings 2 are long and narrow, with a length of... The width of the slot 21 is greater than or equal to the width of the steel baffle 22. The slot 21 is set on the outside of the opening 2. The top of the slot 21 is open and the sides and bottom are closed. The steel baffle 22 is a strip steel plate, including multiple pieces. The steel baffle 22 is 100mm long and 75mm wide. It can be inserted into the slot 21 from the top to close the opening 2. One end of the anchor cable assembly is installed inside the soil layer outside the foundation pit. The other end of the anchor cable assembly passes through the gap between two adjacent steel baffles 22 at the opening 2 and is locked with the anchor 35. The anchor cable assembly includes an anchor cable hole 3, an anchor cable 31, a steel waist beam 32, a pad plate 33, a wedge 34, and an anchor 35. The anchor cable hole 3 is opened inside the soil layer of the pit sidewall. The steel waist beam 32, the pad plate 33, the wedge 34, and the anchor 35 are installed outside the steel baffle 22. The steel waist beam 32 includes two channel steels, which are welded parallel to each other outside the slot 21. The anchor cable 32 is placed in the anchor cable hole 3 and passes through the gap between the opening 2 and the steel waist beam 32, then passes through the pad plate 33 and the wedge 34 in sequence, and is finally locked by the anchor 35. The position where the anchor cable 32 passes through the opening 2 is left by multiple steel baffles 22 stacked above and below. Example

[0024] The difference from Example 1 is that only one anchor cable 31 is constructed, and only one opening 2 is used, while the other opening 2 is sealed with a steel baffle 22.

[0025] In use, the sheet pile 1 is first driven vertically into the soil at the bottom of the foundation pit, with the free end facing inward and the closed end facing outward. The excavation proceeds to the anchor cable installation location, and anchor cable holes 3 are drilled in the soil layer of the foundation pit sidewall through the strip opening 2. Then, multiple steel baffles 22 are inserted into the slots 21 up to the anchor cable holes. Anchor cables 31 are then placed into the anchor cable holes 3, passing through the opening 2. The steel baffles 22 are then inserted into the slots 21 above the anchor cable holes. The anchor cables 31 pass through the steel waist beam 32, steel pad 33, and wedge 34. After prestressing, the anchor cables are finally locked in place using anchorages 35, thus combining the anchor cables 31 and the sheet pile 1 to form a pile-anchor support structure that jointly bears the soil pressure of the foundation pit sidewall.

[0026] If, during construction, the drilling location of anchor cable hole 3 encounters underground obstacles and cannot be drilled, the anchor cable hole 3 can be drilled again after adjusting the drilling distance upwards or downwards within the opening 2 range. Then, the opening 2 can be closed, and the anchor cable 31 can be installed and locked according to the above steps.

Claims

1. An adjustable pre-opened steel sheet pile structure, characterized in that: The assembly includes sheet piles (1), steel baffles (22), and anchor cables (31). The sheet piles (1) have a U-shaped cross-section, with two free ends pointing inward and closed ends pointing outward, and are vertically driven into the stratum at the bottom of the pit. Two openings (2) are opened on the closed ends for setting up two sets of anchor cable assemblies for pit support. A slot (21) is set on the outside of the opening (2), with the top of the slot (21) open and the sides and bottom closed. The steel baffles (22) are strip-shaped steel plates, including multiple pieces, which can be inserted into the slots (21) from the top to close the openings (2). One end of the anchor cable (31) assembly is installed inside the soil layer of the pit sidewall, and the other end of the anchor cable assembly passes through the gap between two adjacent steel baffles (22) at the opening (2) and is locked.

2. The adjustable pre-opened sheet pile structure according to claim 1, characterized in that: The anchor cable assembly includes an anchor cable hole (3), an anchor cable (31), a steel waist beam (32), a pad plate (33), a wedge (34), and an anchor (35). The anchor cable hole (3) is opened inside the soil layer of the pit side wall. The steel waist beam (32), the pad plate (33), the wedge (34), and the anchor (35) are installed outside the steel baffle (22). The steel waist beam (32) includes two channel steels, which are welded parallel to each other outside the slot (21). One end of the anchor cable (31) is placed in the anchor cable hole (3), and the other end is installed with a wedge (34) that passes through the gap between the opening (2) and the steel waist beam (32). The wedge (34) is stuck at the outer end of the steel waist beam (32), and the outer side of the wedge (34) is locked by the anchor (35). The position where the anchor cable (31) passes through the opening (2) is left by multiple steel baffles (22) stacked above and below.

3. The adjustable pre-opened sheet pile structure according to claim 1, characterized in that: The opening (2) is long and narrow, with a length of 600 mm and a width of 60 mm. The width of the slot (21) is greater than or equal to the width of the steel baffle (22).

4. The adjustable pre-opened sheet pile structure according to claim 1, characterized in that: The steel baffle (22) is 100mm long and 75mm wide.

5. The adjustable pre-opened sheet pile structure according to claim 1, characterized in that: The two openings (2) are respectively opened 2m and 4m below the top of the sheet pile (1).

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