Intelligent recyclable fabricated structure for foundation pit support and construction method

Abstract

The application provides an intelligent recyclable assembly structure for foundation pit support, which comprises a retaining structure arranged in the inner side of a foundation pit, and further comprises: a truss arranged in the inner side of the foundation pit retaining structure; an inner support arranged between the retaining structures and used for supporting the two retaining structures; a prestressed bar arranged between the truss bodies on the two sides of the foundation pit and used for adjusting the prestress between the two adjacent trusses; and a displacement monitoring point arranged on the top of the foundation pit; the truss, the waist beam and the prestressed bar are fixed on the existing foundation pit retaining structure, the prestressed bar between the trusses is applied with prestress, the horizontal and vertical displacements of the side wall of the foundation pit are monitored through the displacement monitoring point, the stress information of the prestressed bar and the change information of the foundation pit of the displacement monitoring point are received by a control module, the prestress size is adjusted by the control module to control the prestressed bar, the foundation pit deformation is controlled, and the advantages of automation and steel support are considered.

Description

Technical Field

[0001] This invention relates to the field of civil engineering technology, specifically to an intelligent, recyclable prefabricated structure and construction method for foundation pit support. Background Technology

[0002] Currently, in deep foundation pit support, due to the large depth of the pit and the significant horizontal pressure on the retaining structure, reinforced concrete supports and steel supports are generally selected during the design of the support structure. Reinforced concrete supports differ from steel supports in that they possess high stiffness and low deformation, ensuring the safety of basement and foundation construction, as well as surrounding buildings, roads, and underground pipelines. However, reinforced concrete supports also have significant disadvantages: they are heavy, difficult to recycle, environmentally harmful, do not achieve carbon emission reduction, and are slightly more expensive than steel supports. Steel supports, on the other hand, are lightweight, easy to construct, inexpensive, recyclable, and environmentally friendly. However, they have significant disadvantages: low stiffness, close spacing, and limited space for subsequent construction. Therefore, it is necessary to design a foundation pit support structure that can combine the advantages of both reinforced concrete and steel supports. Summary of the Invention

[0003] This invention provides an intelligent, recyclable, prefabricated structure for foundation pit support, which forms a large-span foundation pit space and an intelligent foundation pit deformation control structure, combining the advantages of concrete support and steel support.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] An intelligent, recyclable, prefabricated structure for foundation pit support includes a retaining structure installed inside the foundation pit, and further includes:

[0006] A truss, wherein the truss is disposed on the inner side of the foundation pit retaining structure;

[0007] Internal supports are provided between the enclosure structures to provide mutual support to the enclosure structures on both sides.

[0008] Prestressed members are installed between the truss frames on both sides of the foundation pit to adjust the prestress between adjacent trusses.

[0009] Displacement monitoring points, located at the top of the excavation pit, are used to detect the deformation of the pit; and

[0010] The control module is connected to the prestressed members and displacement monitoring points. It is used to collect the deformation of the foundation pit and the prestress data of the prestressed members, and to provide feedback to adjust the prestress between the trusses.

[0011] Preferably, the truss includes a horizontally arranged waist beam on the side wall of the enclosure structure, a plurality of steel sections forming a triangular structure along the side wall of the waist beam in a basically parallel manner, a steel plate bracket arranged below the waist beam and connected to the enclosure structure, and columns arranged parallel to the enclosure structure inside the foundation pit for fixing the truss.

[0012] Preferably, the prestressed member includes a prestressing tensioner and anchor heads disposed at both ends of the prestressing tensioner and connected to two adjacent truss frames.

[0013] Preferably, the internal support includes a support body disposed between two opposing waist beams inside the foundation pit and a side rib disposed between the waist beams and the support body.

[0014] Preferably, the displacement monitoring points include monitoring points set at the top of the foundation pit, and a total station for detecting the horizontal and vertical displacement of the borehole, and the total station is connected to the control module via signal.

[0015] Preferably, the control module is an operating terminal connected to the prestressed tensioner and the total station signal.

[0016] A construction method for an intelligent, recyclable prefabricated structure for foundation pit support, as described above, includes the following steps:

[0017] S10: Install waist beams on the enclosure structure;

[0018] S20: Install trusses on the waist beam;

[0019] S30: Install prestressed members between the frames of two adjacent trusses;

[0020] S40: Set up displacement monitoring points at the top of the foundation pit and connect the prestressed tensioner and displacement monitoring points to the control module;

[0021] S50: The prestressing tensioner applies the initial prestress and excavates the foundation pit. The magnitude of the prestress is automatically controlled during the excavation process.

[0022] Preferably, step S20 further includes the following step:

[0023] S210: A truss structure in which steel sections are arranged in a triangular distribution along the side wall of the waist beam;

[0024] S220: Connect internal supports between the waist beams on both sides of the foundation pit.

[0025] Preferably, S30 further includes the steps of installing anchor heads at the top of adjacent trusses and installing prestressed tensioners between the anchor heads.

[0026] Preferably, step S40 includes the following steps:

[0027] S410: Drill holes at the top of the foundation pit and install monitoring points inside the holes;

[0028] S420: Fill the gaps around the borehole and the monitoring point to stabilize the monitoring point;

[0029] S430: Uses a total station to monitor the displacement of the monitoring points and feeds the displacement data back to the control module.

[0030] As can be seen from the above technical solutions, the present invention has the following beneficial effects: When in use, the present invention utilizes trusses, girders, and prestressed members fixed to the existing foundation pit retaining structure. Prestress is applied to the prestressed members between the trusses, and the horizontal and vertical displacements of the foundation pit sidewalls are monitored through displacement monitoring points. The control module receives the force information of the prestressed members and the foundation pit change information from the displacement monitoring points, and can control the prestressed members to adjust the magnitude of the prestress and control the foundation pit deformation through the control module. The present invention forms a large-span foundation pit space and an intelligent foundation pit deformation control structure, taking into account the advantages of automation and steel support. Attached Figure Description

[0031] Figure 1 This is a top view showing the connection between the present invention and the enclosure structure and internal support;

[0032] Figure 2 This is a three-dimensional schematic diagram showing the connection between the present invention and the enclosure structure and internal support;

[0033] Figure 3 This is a three-dimensional schematic diagram of the truss;

[0034] Figure 4 This is a sectional view of the connection between the truss and the enclosure structure.

[0035] Figure 5 A flowchart of the construction method provided by the present invention.

[0036] In the diagram: 10, enclosure structure; 20, truss; 210, wainscoting; 220, steel plate bracket; 230, column; 30, internal support; 310, support body; 320, side rib; 410, prestressed tensioner; 420, anchor head; 50, displacement monitoring point; 60, control module. Detailed Implementation

[0037] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0038] To achieve the above objectives, embodiments of the present invention provide the following technical solutions: (Refer to...) Figure 1An intelligent, recyclable, prefabricated structure for foundation pit support includes a retaining structure 10 disposed inside the foundation pit, trusses 20, internal supports 30, prestressed members 40, displacement monitoring points 50, and a control module 60. The trusses 20 are disposed inside the retaining structure 10, the internal supports 30 are disposed between the retaining structures 10 to form a bracing structure on both sides, the prestressed members 40 are disposed between the truss 20 frames on both sides of the foundation pit and are used to adjust the prestress between adjacent trusses 20, and the displacement monitoring points 50 are located at the top of the foundation pit to detect the deformation of the foundation pit. The control module 60 and the prestressed members... The 40 is connected to the displacement monitoring point 50 to collect the deformation of the foundation pit and the prestress data of the prestressed members 40, and to provide feedback to adjust the prestress between the trusses 20. In use, the trusses, girders and prestressed members are fixed to the existing foundation pit retaining structure. Prestress is applied to the prestressed members between the trusses, and the horizontal and vertical displacement of the foundation pit sidewalls is monitored through the displacement monitoring points. The control module receives the force information of the prestressed members and the foundation pit change information from the displacement monitoring points, and can control the prestressed members to adjust the prestress and control the foundation pit deformation. This invention forms a large-span foundation pit space and an intelligent foundation pit deformation control structure, which combines the advantages of automation and steel support.

[0039] Reference Figure 2 , Figure 4 As a preferred technical solution in this embodiment, the truss 20 includes a waist beam 210, steel sections, steel plate brackets 220, and columns 230. The waist beam 210 is horizontally arranged on the side wall of the retaining structure 10. This waist beam is used to transfer the load of the retaining structure, and the waist beam can be made of H-beams or I-beams. There are multiple steel sections, and the multiple steel sections form a triangular structure along the side wall of the waist beam 210 in a basically parallel manner. That is, multiple steel sections are connected end to end along the side wall of the waist beam to form a triangular steel structure extending from the waist beam into the inside of the foundation pit. Furthermore, in order to realize the connection between the waist beam 210 and the retaining structure 10... For a stable connection, a steel plate bracket 220 is installed below the waist beam 210 and fixed to the inner wall of the enclosure structure 10. Specifically, the steel plate bracket can be welded to the inner wall of the enclosure structure 10. The column 230 is set parallel to the enclosure structure 10 and can be fixedly welded to the end of the steel section away from the waist beam. In use, the steel section can be connected to the waist beam with high-strength bolts. Adjacent steel sections can be fixed by welding. The truss is fixed to the side wall of the enclosure structure through the cooperation of the steel plate bracket and the column. The steel plate bracket is made of cut steel plate welded to the enclosure structure. The column is made of four angle steel spliced ​​to form a square lattice column.

[0040] Reference Figure 2 , Figure 3As a preferred technical solution in this embodiment, the prestressed member includes a prestressing tensioner 410 and anchor heads 420 disposed at both ends of the prestressing tensioner 410 and connected to the adjacent two truss frames 20. In use, the prestressing tensioner is fixed between the two adjacent truss frames by the anchor heads. The anchor heads can be made of steel strand or other steel materials. It should be noted that the prestressing tensioner allows the trusses on both sides to form a tension, which can apply prestress to the truss. Different models of tensioners such as MD18 / 300 / 55, MD / 19 / 300 / 55, and MD19 / 400 / 55 can be used according to the required prestress.

[0041] Reference Figure 2 As a preferred technical solution in this embodiment, the inner support 30 includes a support body 310 and a side rib 320. The support body 310 is disposed between two opposite waist beams 210 inside the foundation pit, and the side rib 320 is disposed between the waist beam 210 and the support body 310. The side rib 320 forms a triangular structure between the inner support 30 and the waist beam to provide support force for the waist beam, thereby improving the stability of the connection between the inner support and the waist beam. Furthermore, the support body and the side rib can be made of H-beams or steel pipes.

[0042] As a preferred technical solution in this embodiment, the displacement monitoring point 50 includes a monitoring point set at the top of the foundation pit and a total station for detecting the horizontal and vertical displacement of the borehole. The total station is connected to the control module. In use, a borehole is drilled at the top of the foundation pit, and the monitoring point is set up in the borehole. That is, the monitoring point of the total station is placed in the borehole, and the gap between the borehole and the monitoring point is filled with cement mortar, anchoring agent, or rebar adhesive to achieve the purpose of fixing and stabilizing the monitoring point. In this way, the deformation of the foundation pit can be monitored by measuring the points, that is, the horizontal and vertical displacement of the foundation pit can be monitored by the total station, and the data results can be fed back to the control module.

[0043] Furthermore, the control module 60 is an operation terminal connected to the prestressed tensioner 410 and the total station. This operation terminal is connected to the prestressed tensioner and the total station. By collecting the axial force information and foundation pit deformation fed back by the prestressed members, the force of the prestressed tensioner can be adjusted according to the axial force information fed back by the prestressed members, thereby controlling the foundation pit deformation and ensuring that the axial force of the prestressed members meets the design requirements.

[0044] Reference Figure 5 The present invention also provides a construction method for an intelligent recyclable prefabricated structure for foundation pit support, comprising the following steps:

[0045] S10: Install a wainscoting on the enclosure structure.

[0046] Specifically, a waist beam is installed on the existing foundation pit retaining structure. This can be achieved by setting steel plate brackets at the bottom and welding them on the inside to fix the waist beam to the side wall of the retaining structure in a manner parallel to the bottom of the foundation pit.

[0047] S20: Install trusses on the waist beam.

[0048] Specifically, after the waist beam is fixed, the truss is fixed to the side wall of the waist beam in a manner parallel to the bottom of the pit, forming a triangular steel structure extending from the waist beam into the pit.

[0049] S30: Prestressed members are installed between the frames of two adjacent trusses.

[0050] Specifically, after the truss and the waist beam are fixed, prestressed members are installed between the frames of two adjacent trusses. These prestressed members are used to apply prestress to the truss, and the magnitude of the prestress on the truss can be adjusted.

[0051] S40: Set up a displacement monitoring point at the top of the foundation pit and connect the prestressed tensioner and the displacement monitoring point to the control module.

[0052] Specifically, boreholes are drilled at the top of the foundation pit, and displacement monitoring points are arranged inside the boreholes to monitor the spatial displacement of the foundation pit. Specifically, the measuring points of the total station are set inside the boreholes and filled and fixed, thereby enabling the total station to be electrically connected to the control module.

[0053] S50: The prestressing tensioner applies the initial prestress and excavates the foundation pit. The magnitude of the prestress is automatically controlled during the excavation process.

[0054] Specifically, after the aforementioned S10-S40 are completed, the initial prestress is applied to the truss through a prestressing tensioner, followed by the excavation of the foundation pit. During the excavation process, the horizontal and vertical displacements of the foundation pit are monitored through displacement monitoring points, and the prestress on the truss is controlled through the prestressing tensioner.

[0055] Furthermore, S20 also includes the following steps:

[0056] S210: A truss structure in which steel sections are arranged in a triangular distribution along the side wall of the waist beam.

[0057] Specifically, when installing the truss, the steel sections are arranged into a triangular steel structure along the side wall of the waist beam, thereby utilizing the stability of the triangle to improve the connection stability between the truss and the waist beam.

[0058] S220: Connect internal supports between the waist beams on both sides of the foundation pit.

[0059] Specifically, after the steel section is connected to the waist beam, internal supports are connected between the waist beams on both sides of the foundation pit to improve the stability of the connection between the truss and the waist beam.

[0060] Furthermore, S30 also includes the step of installing anchor heads on the top of adjacent trusses and installing prestressed tensioners between the anchor heads. Specifically, anchor heads are set at both ends of the prestressed tensioners, and the anchor heads are connected to the adjacent two truss frames. The anchor heads can be made of steel strands or other steel materials, thereby realizing the installation of the prestressed tensioners and trusses.

[0061] Furthermore, S40 includes the following steps:

[0062] S410: Drill holes at the top of the foundation pit and install monitoring points inside the holes.

[0063] Specifically, when setting up displacement monitoring points, it is necessary to first drill holes at the top of the foundation pit and then install stainless steel probes inside the holes.

[0064] S420: Fill the gaps around the borehole and monitoring point to stabilize the monitoring point.

[0065] Specifically, after the monitoring point is installed, the gap between the monitoring point and the borehole is filled and fixed with cement mortar, anchoring agent, or rebar anchoring agent to prevent the monitoring point from being misaligned, so as to monitor the deformation of the foundation pit through the monitoring point.

[0066] S430: Uses a total station to monitor the displacement of the monitoring points and feeds the displacement data back to the control module.

[0067] Specifically, during the excavation of the foundation pit, the displacement of the monitoring points is measured using a total station, and the monitoring data is fed back to the control module in real time.

[0068] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An intelligent, recyclable, prefabricated structure for foundation pit support, comprising a retaining structure (10) disposed on the inner side of the foundation pit, characterized in that, Also includes: Truss (20), said truss (20) is disposed inside the enclosure structure (10); An inner support (30) is provided between the enclosure structures (10) to provide mutual support for the enclosure structures (10) on both sides; Prestressed members (40) are set between the truss (20) frames on both sides of the foundation pit to adjust the prestress between two adjacent trusses (20); Displacement monitoring point (50), the displacement monitoring point (50) is set at the top of the foundation pit, and is used to detect the deformation of the foundation pit; as well as The control module (60) is connected to the prestressed members (40) and the displacement monitoring point (50) to collect the deformation of the foundation pit and the prestress data of the prestressed members (40), and to provide feedback to adjust the prestress between the trusses (20); The prestressed member (40) includes a prestressed tensioner (410) and anchor heads (420) located at both ends of the prestressed tensioner (410) and connected to the frame of the two adjacent trusses (20). The displacement monitoring point (50) includes a monitoring point set at the top of the foundation pit, and a total station for detecting the horizontal and vertical displacement of the borehole, and the total station is connected to the control module signal. The truss (20) includes a waist beam (210) horizontally arranged on the side wall of the enclosure structure (10), a plurality of steel sections forming a triangular structure along the side wall of the waist beam (210) in a basically parallel manner, a steel plate bracket (220) arranged below the waist beam (210) and connected to the enclosure structure (10), and a column (230) parallel to the enclosure structure (10) and arranged inside the pit for fixing the truss (20).

2. The intelligent recyclable prefabricated structure for foundation pit support according to claim 1, characterized in that, The inner support (30) includes a support body (310) disposed between two opposite waist beams (210) on the inner side of the foundation pit and a side rib (320) disposed between the waist beams (210) and the support body (310).

3. The intelligent recyclable prefabricated structure for foundation pit support according to claim 1, characterized in that, The control module (60) is an operating terminal that is connected to the prestressed tensioner (410) and the total station signal.

4. A construction method for an intelligent recyclable prefabricated structure for foundation pit support according to any one of claims 1-3, characterized in that, Includes the following steps: S10: Install waist beams on the enclosure structure; S20: Install trusses on the waist beam; S30: Install prestressed members between the frames of two adjacent trusses; S40: Set up displacement monitoring points at the top of the foundation pit and connect the prestressed tensioner and displacement monitoring points to the control module; S50: The prestressing tensioner applies the initial prestress and excavates the foundation pit. The magnitude of the prestress is automatically controlled during the excavation process.

5. The construction method for the intelligent recyclable prefabricated structure for foundation pit support according to claim 4, characterized in that, S20 further includes the following steps: S210: A truss structure in which steel sections are arranged in a triangular distribution along the side wall of the waist beam; S220: Connect internal supports between the waist beams on both sides of the foundation pit.

6. The construction method for the intelligent recyclable prefabricated structure for foundation pit support according to claim 5, characterized in that, S30 further includes the steps of installing anchor heads at the top of adjacent trusses and installing prestressed tensioners between the anchor heads.

7. The construction method for the intelligent recyclable prefabricated structure for foundation pit support according to claim 6, characterized in that, S40 includes the following steps: S410: Drill holes at the top of the foundation pit and install monitoring points inside the holes; S420: Fill the gaps around the borehole and the monitoring point to stabilize the monitoring point; S430: Uses a total station to monitor the displacement of the monitoring points and feeds the displacement data back to the control module.

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