High-voltage line under shallow excavation construction steel sheet pile platform foundation pit structure

Abstract

The utility model discloses a shallow excavation construction steel sheet pile platform foundation pit structure under high voltage line belongs to foundation pit structure technology, solves the problem of small space under high voltage line, and it is difficult to construct construction. It includes foundation pit, and the both sides of the top of foundation pit are equipped with reinforcing layer, and the depth of reinforcing layer is 1m~2m, the reinforcing layer includes inner mixed layer, rammed soil layer and outer mixed layer, the inner mixed layer, rammed soil layer, outer mixed layer are sequentially arranged along the side away from foundation pit, the inner mixed layer, outer mixed layer all are the reinforcing wall that cement powder, brick residue, soil are rammed by hydraulic rammer, and the density of inner mixed layer is greater than the density of outer mixed layer, and the rammed soil layer is the virgin soil layer that is rammed by hydraulic rammer, be equipped with foundation pit support structure in the foundation pit. The utility model can realize economic, fast, safe construction in the narrow space under high voltage line.

Description

Technical Field

[0001] This utility model relates to the field of foundation pit support structure technology, and more specifically, it relates to a foundation pit structure for a steel sheet pile platform for shallow excavation under high voltage line. Background Technology

[0002] Construction of sheet piles under high-voltage lines faces strict safety distance restrictions (110kV vertical distance ≥5m, 220kV ≥6m). However, the length of conventional sheet piles (≥9m) combined with the height of construction machinery can easily exceed the safety limits, posing risks of electric shock, equipment damage, and large-scale power outages, with economic losses reaching tens of thousands of yuan per minute.

[0003] like Figure 1 As shown, taking a project with a 10KV high-voltage line 16 at the construction site, whose height H above the ground is 12 meters as an example: According to relevant safety regulations, the minimum safe distance b for construction under high-voltage lines is 3 meters. Therefore, the safe construction distance c needs to reach 9 meters. After calculation, if the length of the sheet pile is 9 meters, in actual construction, factors such as the height of construction equipment and operating space need to be taken into account. This will result in an additional 1-2 meters of construction space. In traditional construction methods, when directly driving the sheet piles into the ground using a pile driver, the highest point of the pile driver will exceed the safe construction distance, making it impossible to carry out standardized construction. The short piles can only be connected by welding, but welding under high-voltage lines can also easily cause safety problems.

[0004] Therefore, it is necessary to design a foundation pit structure that can be constructed in the confined space of high-voltage lines to solve the aforementioned technical problems. Utility Model Content

[0005] The technical problem to be solved by this utility model is to address the above-mentioned shortcomings of the existing technology. Its purpose is to provide a steel sheet pile platform foundation pit structure for shallow excavation under high voltage line, which can realize construction in a narrow space under high voltage line and improve construction safety.

[0006] The technical solution of this utility model is as follows: a steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines, comprising a foundation pit, with reinforcement layers on both sides of the top of the foundation pit, the reinforcement layers having a depth of 1m to 2m, the reinforcement layers comprising an inner mixed layer, a compacted soil layer, and an outer mixed layer, the inner mixed layer, the compacted soil layer, and the outer mixed layer being arranged sequentially along the side away from the foundation pit, the inner mixed layer and the outer mixed layer being reinforcement walls formed by compacting cement powder, brick debris, and soil with a hydraulic rammer, and the density of the inner mixed layer being greater than the density of the outer mixed layer, the compacted soil layer being the original soil layer formed by compacting with a hydraulic rammer; a foundation pit support structure is provided inside the foundation pit.

[0007] As a further improvement, the width of the compacted soil layer is greater than the width of the inner and outer mixing layers.

[0008] Furthermore, the width of the inner mixing layer is greater than the width of the outer mixing layer.

[0009] Furthermore, the depth of the compacted soil layer is less than the depth of the inner and outer mixing layers.

[0010] Furthermore, the depth of the inner mixing layer is greater than the depth of the outer mixing layer.

[0011] Furthermore, the foundation pit support structure includes multiple Larssen sheet piles that are inserted and fixed to the ground on both sides of the foundation pit. Two adjacent Larssen sheet piles interlock to form a foundation pit retaining wall. A steel waist beam is installed on the inner side of the foundation pit retaining wall. A supporting steel pipe is installed between the two steel waist beams corresponding to the foundation pit retaining walls to tighten the two foundation pit retaining walls together.

[0012] Furthermore, the steel waist beam is detachably connected to the foundation pit retaining wall and supporting steel pipes.

[0013] Furthermore, a reinforcing plate is provided between the middle of the steel waist beam and the foundation pit retaining wall.

[0014] Furthermore, a steel waist beam is installed on each side of the foundation pit enclosure, and the steel waist beam is an I-beam.

[0015] Beneficial effects

[0016] Compared with the prior art, this utility model has the following advantages:

[0017] This utility model relates to a shallow excavation steel sheet pile platform foundation pit structure. It involves shallow excavation of a construction platform under high-voltage lines. By intermittently mixing brick debris and cement on both sides of the foundation pit, and then using a hydraulic rammer to process the soil, a reinforcement layer is created, consisting of an inner mixed layer, a compacted soil layer, and an outer mixed layer. This effectively improves soil parameters such as density and strength, enabling vertical excavation and creating a stable construction space. An excavator can directly excavate a temporary foundation pit several meters deep within the reinforcement layer to serve as a settlement platform. Due to the presence of the reinforcement layer, the soil around the foundation pit will not collapse, allowing the pile driver to enter the settlement platform for steel sheet pile construction. Furthermore, because the pile driver operates within the settlement platform, its height is reduced, successfully avoiding the safety protection zone of the high-voltage lines. This enables economical, rapid, and safe foundation pit construction in confined spaces under high-voltage lines. Attached Figure Description

[0018] Figure 1 This is a side view diagram of the existing technology;

[0019] Figure 2 This is a side view of the structure of this utility model;

[0020] Figure 3 for Figure 2 Enlarged structural diagram at point A;

[0021] Figure 4 This is a top view of the foundation pit structure in this utility model;

[0022] Figure 5 This is an enlarged side view of the connection between the foundation pit retaining structure and the steel waist beam of this utility model;

[0023] Figure 6 This is a construction drawing of the reinforcement layer in this utility model;

[0024] Figure 7 This is a construction drawing of the settlement platform in this utility model;

[0025] Figure 8 This is a construction drawing of the foundation pit support structure in this utility model.

[0026] The components include: 1. Excavation pit; 2. Inner mixed layer; 3. Compacted soil layer; 4. Outer mixed layer; 5. Larssen sheet piles; 6. Excavation pit retaining wall; 7. Steel waist beam; 8. Supporting steel pipe; 9. Reinforced plate; 10. High-voltage line; 11. Hydraulic rammer; 12. Pile driver; 13. Excavator; 14. Settlement platform. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0028] See Figure 2-8This utility model discloses a shallow excavation steel sheet pile platform foundation pit structure under high voltage line, including a foundation pit 1. Reinforcement layers are provided on both sides of the top of the foundation pit 1. For shallow foundation pits, such as a foundation pit with a depth of 4m, the depth of the reinforcement layer is 1m to 2m. In this embodiment, the depth of the reinforcement layer is preferably 2m to avoid collapse when the platform 14 is excavated and settled. The reinforcement layer in this embodiment includes an inner mixed layer 2, a compacted soil layer 3, and an outer mixed layer 4. The inner mixed layer 2, the compacted soil layer 3, and the outer mixed layer 4 are arranged sequentially along the side away from the foundation pit 1, forming a three-tiered reinforcement and protection. Specifically, the inner mixed layer 2 and the outer mixed layer 4 are both reinforced walls formed by compacting cement powder, brick slag, and soil with a hydraulic rammer. The density of the inner mixed layer 2 is greater than that of the outer mixed layer 4, meaning that the material density of the inner mixed layer 2 per unit volume is greater than that of the outer mixed layer 4. In actual construction, different weights of cement powder, brick slag, and soil can be added to achieve the desired difference in density. The higher density of the inner mixed layer 2 can further ensure that the settlement platform 14 will not collapse, while the relatively weaker outer mixed layer 2 has a relatively lower density, which can reduce material consumption and lower costs. The compacted soil layer 3 is the original soil layer formed by compacting with a hydraulic rammer, without using any materials, which meets the reinforcement requirements while further reducing costs.

[0029] In this embodiment of the shallow foundation pit structure, during construction:

[0030] S1. Based on the existing open area elevation, determine the safe construction distance and the required vertical excavation depth. Determine the proportion of brick slag and cement to be added based on the excavation depth. First, use a hydraulic rammer 11 to compact the soil on both sides of the foundation pit 1, obtaining a compacted soil layer 3. Then, repeatedly sprinkle brick slag and cement powder on both sides of the compacted soil layer 3 and compact them separately with the hydraulic rammer 11, finally obtaining an inner mixed layer 2 and an outer mixed layer 4 (e.g., ...). Figure 6 (as shown);

[0031] S2, excavator 13 excavates the soil between the two inner mixed layers 2 to the required depth, obtaining the settlement platform 14 (e.g., Figure 7 (as shown);

[0032] S3, Piling machine 12 enters the settlement platform 14 for construction, driving Larssen sheet piles 5 into the inner wall of the settlement platform 14, finally obtaining the foundation pit retaining wall 6 (such as...). Figure 8 As shown in the figure, this facilitates the continued excavation of foundation pit 1 and enables safe construction under high-voltage lines.

[0033] This utility model discloses a shallow foundation pit structure for use under high-voltage power lines. By intermittently mixing brick slag and cement on both sides of the foundation pit 1, and then using a hydraulic rammer to process it, a reinforcement layer consisting of an inner mixed layer 2, a compacted soil layer 3, and an outer mixed layer 4 is obtained. This effectively improves soil parameters such as density and strength, enabling the soil to be excavated vertically, thus creating a stable construction space. An excavator can directly excavate a temporary foundation pit several meters deep within the reinforcement layer as a settlement platform for construction. Due to the presence of the reinforcement layer, the soil around the foundation pit will not collapse, allowing the pile driver to enter the settlement platform for sheet pile construction. Furthermore, because the pile driver operates within the settlement platform, its height is reduced, successfully avoiding the safety protection zone of the high-voltage power line. This enables construction in confined spaces under high-voltage power lines, improving construction safety.

[0034] Preferably, the width of the compacted soil layer 3 is greater than the width of the inner mixing layer 2 and the outer mixing layer 4. A wider compacted soil layer 3 provides better reinforcement, and its width also reduces the material required for the inner and outer mixing layers 2 and 4, thus lowering costs. Furthermore, the width of the inner mixing layer 2 is greater than the width of the outer mixing layer 4; using a wider inner mixing layer 2 further enhances the reinforcement effect. The depth of the compacted soil layer 3 is less than the depth of the inner and outer mixing layers 2, while the depth of the inner mixing layer 2 is greater than the depth of the outer mixing layer 4. This creates a stepped structure for the reinforcement layers, further improving the reinforcement effect while reducing material consumption and costs.

[0035] In this embodiment, a foundation pit support structure is provided in the foundation pit 1. The foundation pit support structure includes multiple Larssen steel sheet piles 5 that are inserted and fixed to the ground on both sides of the foundation pit 1. Two adjacent Larssen steel sheet piles 5 interlock with each other to form a foundation pit retaining wall 6. A steel waist beam 7 is installed on the inner side of the foundation pit retaining wall 6. A supporting steel pipe 8 is installed between the steel waist beams 7 corresponding to the two foundation pit retaining walls 6 to tighten the two foundation pit retaining walls 6, which is used to reinforce the relative symmetry of the foundation pit retaining wall 6 and avoid the problem of the soil on both sides damaging the foundation pit retaining wall 6.

[0036] Preferably, the steel waist beam 7 is detachably connected to the foundation pit retaining wall 6 and the supporting steel pipe 8. Specifically, the steel waist beam 7 can be connected to the foundation pit retaining wall 6 and the supporting steel pipe 8 by bolts, which facilitates disassembly and assembly.

[0037] Preferably, a reinforcing plate 9 is provided between the middle of the steel waist beam 7 and the foundation pit retaining wall 6 to reinforce the steel waist beam 7 and improve the installation stability of the steel waist beam 7. The reinforcing plate 9 is also connected to the steel waist beam 7 and the foundation pit retaining wall 6 by bolts for easy disassembly and assembly.

[0038] Preferably, a steel wainscoting 7 is installed on each side of the foundation pit retaining wall 6, which is suitable for the support of shallow foundation pits, improves construction efficiency, and the steel wainscoting 7 is an I-beam, which improves the structural strength of the steel wainscoting 7.

[0039] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present utility model, and these will not affect the implementation effect of the present utility model or the practicality of the patent.

Claims

1. A steel sheet pile platform foundation pit structure for shallow excavation under high voltage line, comprising a foundation pit (1), characterized in that, The top two sides of the foundation pit (1) are provided with reinforcement layers. The depth of the reinforcement layers is 1m to 2m. The reinforcement layers include an inner mixed layer (2), a compacted soil layer (3) and an outer mixed layer (4). The inner mixed layer (2), the compacted soil layer (3) and the outer mixed layer (4) are arranged in sequence along the side away from the foundation pit (1). The inner mixed layer (2) and the outer mixed layer (4) are both reinforcement walls formed by compacting cement powder, brick slag and soil with a hydraulic rammer. The density of the inner mixed layer (2) is greater than that of the outer mixed layer (4). The compacted soil layer (3) is the original soil layer formed by compacting with a hydraulic rammer. The foundation pit (1) is provided with a foundation pit support structure.

2. The steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to claim 1, characterized in that, The width of the compacted soil layer (3) is greater than the width of the inner mixed layer (2) and the outer mixed layer (4).

3. The steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to claim 1, characterized in that, The width of the inner mixing layer (2) is greater than the width of the outer mixing layer (4).

4. The steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to claim 1, characterized in that, The depth of the compacted soil layer (3) is less than the depth of the inner mixed layer (2) and the outer mixed layer (4).

5. The steel sheet pile platform foundation pit structure for shallow excavation under high voltage lines according to claim 1, characterized in that, The depth of the inner mixing layer (2) is greater than the depth of the outer mixing layer (4).

6. A steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to any one of claims 1-5, characterized in that, The foundation pit support structure includes multiple Larssen sheet piles (5) that are inserted and fixed to the ground on both sides of the foundation pit (1). Two adjacent Larssen sheet piles (5) interlock to form a foundation pit retaining wall (6). A steel waist beam (7) is installed on the inner side of the foundation pit retaining wall (6). A supporting steel pipe (8) is installed between the steel waist beams (7) corresponding to the two foundation pit retaining walls (6) to tighten the two foundation pit retaining walls (6).

7. The steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to claim 6, characterized in that, The steel waist beam (7) is detachably connected to the foundation pit retaining wall (6) and the supporting steel pipe (8).

8. The steel sheet pile platform foundation pit structure for shallow excavation under high voltage line construction according to claim 6, characterized in that, A reinforcing plate (9) is also provided between the middle of the steel waist beam (7) and the foundation pit retaining wall (6).

9. A steel sheet pile platform foundation pit structure for shallow excavation under high-voltage lines according to claim 6, characterized in that, Each side of the foundation pit retaining wall (6) is equipped with a corresponding steel waist beam (7), and the steel waist beam (7) is an I-beam.

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