River-adjacent bias pressure foundation pit enclosure structure

Abstract

The utility model relates to the technical field of civil engineering, specifically relates to a river-adjacent bias foundation pit support structure, including the support body, the crown beam, the waist beam and the inner support, the soil body in the other side of the foundation pit support structure is provided with the beam type anchorage, one end of steel strand is connected with the beam type anchorage, after the steel strand tension, its other end is connected with the crown beam and / or the waist beam and is fixed, the utility model has the advantages of: 1) mainly using the trenchless technology implementation, not affecting the river and the influence of ground pipeline and traffic is smaller, 2) can effectively coordinate the support axial force and the foundation pit displacement through the adjustment steel strand's tension value or tension, has stronger artificial controllability, 3) can be used as the passageway of municipal pipeline after construction completion.

Description

Technical Field

[0001] This utility model relates to the field of civil engineering technology, specifically to a retaining structure for a river-adjacent biased foundation pit. Background Technology

[0002] When a foundation pit is close to a river or ditch, the soil on the river-adjacent side is usually thinner and limited in scope, unable to generate matching soil pressure or provide sufficient resistance. Significant differences in soil density can lead to large displacement towards the river, even causing the foundation pit to collapse. Common methods to achieve balance include cement-soil reinforcement between the foundation pit and the river, sandbag ballast within the river channel, and dewatering the soil on the opposite side of the river to reduce water and soil pressure. However, cement-soil reinforcement is unreliable when the soil is thin and often involves significant relocation with pipelines. Sandbag ballast within the river channel can obstruct the river's cross-section, and dewatering can cause ground subsidence. Therefore, all these methods have limitations. Summary of the Invention

[0003] The purpose of this utility model is to address the shortcomings of the existing technology by providing a retaining structure for a river-adjacent biased foundation pit. This structure relies on steel strands pulled to beam-type anchorages constructed using pipe jacking and deeply buried in the soil to dissolve the unbalanced force of the biased foundation pit. Simultaneously, the axial force or displacement of the foundation pit can be controlled by adjusting the tension force or tension amount.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A river-adjacent eccentric foundation pit retaining structure includes a foundation pit retaining structure with one side adjacent to a river. The foundation pit retaining structure includes a retaining body, a capping beam, a waist beam, and internal supports. The retaining body is arranged around the foundation pit. The capping beam is located on top of the retaining body. The internal supports are erected between the capping beams on opposite sides. The waist beam is located inside the retaining body and below the capping beam. The internal supports are also erected between the waist beams on opposite sides. The characteristic feature is that a beam-type anchor is installed in the soil on the other side of the foundation pit retaining structure. One end of the beam-type anchor is connected to a steel strand. After the steel strand is tensioned, its other end is connected and fixed to the capping beam and / or the waist beam.

[0006] The beam-type anchorage has working wells at both ends, and the beam-type anchorage is constructed by jacking and runs horizontally between the working wells at both ends.

[0007] The crown beam and the waist beam are respectively provided with reserved holes, and the beam anchorage is provided with anchor holes.

[0008] The beam-type anchor has an internal cavity.

[0009] The beam-type anchorage is set at least 5m behind the theoretical straight fracture surface of the foundation pit.

[0010] The advantages of this utility model are:

[0011] 1) The project mainly adopts trenchless technology, which does not affect the river channel and has little impact on ground pipelines and traffic.

[0012] 2) The tension value or tension amount of the steel strand can be adjusted to effectively coordinate the axial force of the support and the displacement of the foundation pit, which has strong artificial controllability.

[0013] 3) It can be used as a channel for municipal pipelines after construction is completed.

[0014] 4) It has good reliability, good innovation and application value, and is worth promoting. Attached Figure Description

[0015] Figure 1 This is a plan view of the present invention;

[0016] Figure 2 This is a cross-sectional schematic diagram of the present invention;

[0017] Figure 3 This is a schematic diagram of the structure of the beam-type anchorage of this utility model;

[0018] Figure 4 This is a cross-sectional view of the beam-type anchorage of this utility model;

[0019] Figure 5 This is a construction step diagram of the present invention. Detailed Implementation

[0020] The features of this utility model and other related features will be further described in detail below with reference to the accompanying drawings and embodiments, so as to facilitate the understanding of those skilled in the art:

[0021] like Figure 1-5 As shown in the figure, numbers 1-9 represent: working well 1, beam anchorage 2, steel strand 3, internal support 4, waist beam 5, cap beam 6, enclosure 7, theoretical straight fracture surface 8, and anchor hole 9.

[0022] Example: Figures 1 to 5 As shown, in this embodiment, the retaining structure for the foundation pit with bias pressure adjacent to the river is used to solve the bias pressure problem of the foundation pit adjacent to the river and ditch, and can occupy less ground resources without causing pipeline relocation, traffic organization and changes in river cross-section.

[0023] Specifically, combined Figure 1 and Figure 2As shown in the diagram, with the direction illustrated, the left side of the foundation pit retaining structure in this embodiment is adjacent to the river. It includes a retaining body 7, a capping beam 6, a waist beam 5, and internal supports 4. The retaining body 7 is constructed using retaining piles or a retaining wall, which surrounds the foundation pit. The capping beam 6 is located at the top of the retaining body 7, and internal supports 4 are installed between the opposite capping beams 6. The waist beam 5 is located inside the retaining body 7 and below the capping beam 6, with internal supports 4 installed between the opposite waist beams 5. The internal supports are used to resist inward forces from outside the foundation pit.

[0024] Combination Figure 1 and Figure 2 As shown, a beam-type anchorage 2 is installed in the soil on the opposite side of the foundation pit retaining structure from the adjacent river. The beam-type anchorage 2 is a hollow structure with a cavity, and anchor holes 9 are provided on its side adjacent to the foundation pit retaining structure. One end of a steel strand 3 is connected to the anchor hole 9 of the beam-type anchorage 2. After the steel strand 3 is tensioned, its other end is connected and fixed to the cap beam 6 and the waist beam 5.

[0025] At this time, the unbalanced water and soil pressure and the displacement of the foundation pit are adjusted by tensioning the steel strands 3 that connect the waist beam 5 or the cap beam 6 of the foundation pit to the beam anchor 2. In particular, adjusting the tension force or tension amount of the steel strands 3 can control the axial force of the foundation pit or the displacement of the foundation pit.

[0026] In this embodiment, reserved holes are provided on the crown beam 6 and the waist beam 5 respectively, which facilitates the connection of the steel strands 3.

[0027] like Figure 5 As shown, this embodiment includes the following steps when applied:

[0028] 1) Based on the calculated theoretical straight fracture surface of the foundation pit and combined with the ground conditions, determine the positions of the beam anchor 2 and the working well 1. The beam anchor 2 is set at a position not less than 5m after the theoretical straight fracture surface 8 of the foundation pit to ensure that the beam anchor 2 is stable and can provide sufficient tension to the foundation pit retaining structure through the steel strand 3.

[0029] 2) Excavate vertically downward working wells 1 at both ends of the designed position of the beam anchor 2. The depth of the working wells 1 meets the construction requirements of the beam anchor 2.

[0030] 3) Construct beam-type anchorage 2 and carry it out in sections by jacking in working shaft 1.

[0031] 4) Construct retaining structure 7 for the foundation pit to be built. Excavate to below the elevation of the capping beam 6, construct the capping beam 6, and reserve holes for steel strands 3, which also serve as drilling rig positioning holes. Drill high-precision holes in the reserved holes of the capping beam 6, facing the anchor holes 9 of the beam-type anchorage 2, and insert corrugated pipes into the holes. Insert steel strands 3 into the corrugated pipes and tension them to the pre-calculated design value.

[0032] 5) Continue excavating the soil downwards to below the next inner support 4, erect the waist beam 5 with pre-reserved holes, drill holes in the waist beam 5 to the beam anchor 2, repeat the process of threading corrugated pipes, threading steel strands 3, tensioning steel strands 3, etc., until the construction of all steel strands 3 is completed.

[0033] 6) During the excavation of the foundation pit, data such as axial force and displacement of the foundation pit should be monitored in real time, and the tension or tension amount of the steel strand 3 should be adjusted in a timely manner according to the monitoring data.

[0034] In this embodiment, the beam anchorage 2, due to its hollow internal cavity structure, can be directly accessed as a construction area during construction, facilitating the construction and adjustment of the steel strand 3. Furthermore, after construction is completed, it can be used as a channel for municipal pipelines.

[0035] Although the above embodiments have described the concept and embodiments of the present invention in detail with reference to the accompanying drawings, those skilled in the art will recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, and therefore will not be elaborated here.

Claims

1. A retaining structure for a river-adjacent, biased foundation pit, comprising a foundation pit retaining structure, one side of which is adjacent to a river, the retaining structure comprising a retaining body, a capping beam, a waist beam, and internal supports, wherein the retaining body is arranged around the foundation pit, the capping beam is located on top of the retaining body, the internal supports are erected between the capping beams on opposite sides, the waist beams are located inside the retaining body and below the capping beams, and the internal supports are erected between the waist beams on opposite sides, characterized in that: A beam-type anchor is installed in the soil on the other side of the foundation pit retaining structure. One end of the beam-type anchor is connected to a steel strand. After the steel strand is tensioned, its other end is connected and fixed to the cap beam and / or the waist beam.

2. The retaining structure for a river-adjacent, biased foundation pit according to claim 1, characterized in that: The beam-type anchorage has working wells at both ends, and the beam-type anchorage is constructed by jacking and runs horizontally between the working wells at both ends.

3. The retaining structure for a river-adjacent, biased foundation pit according to claim 1, characterized in that: The crown beam and the waist beam are respectively provided with reserved holes, and the beam anchorage is provided with anchor holes.

4. The retaining structure for a river-adjacent, biased foundation pit according to claim 1, characterized in that: The beam-type anchor has an internal cavity.

5. The retaining structure for a river-adjacent, biased foundation pit according to claim 1, characterized in that: The beam-type anchorage is set at least 5m behind the theoretical straight fracture surface of the foundation pit.

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