A recyclable assembly type steel casing kit

Abstract

The utility model discloses a recoverable assembly type steel casing suite, including steel casing, the steel casing is from top to bottom by multilayer annular assembly type steel casing is composed, and the assembly type steel casing of each layer is assembled to four arc assembly and connecting piece, and the arc assembly of same layer is assembled type fixed connection through connecting piece between, and the arc assembly between upper and lower two layers is fixed through the positioning connecting piece, compared with prior art, the utility model is safe and reliable, and the buckling margin satisfies the requirement, and the internal support guarantees the temporary stability, and the sectional assembly is high in construction efficiency for artificial + mechanical cooperation, and can be recycled and reused for many times, reduces the cost, and is economic and environmental protection, is suitable for the shallow foundation pit and pipe well construction under the soft soil / saturated soil layer condition of similar area.

Description

Technical Field

[0001] This utility model relates to the field of municipal drainage pipeline excavation and construction support, and in particular to a recyclable prefabricated steel casing kit. Background Technology

[0002] In current municipal drainage pipeline maintenance and construction processes, projects involving excavation typically involve either excavating the foundation pit and then using a reverse method to lift the manhole, or excavating the foundation pit and then using an excavator to drive in steel casings as support. However, the reverse method involves cast-in-place concrete manhole support that is non-recyclable, has a long construction period, and is costly. Ordinary steel casings, on the other hand, require a heavy body, are inconvenient to transport, are non-recyclable, and are also costly. Furthermore, both methods suffer from insufficient safety during temporary excavation and low installation / removal efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a recyclable prefabricated steel casing kit that enables rapid, recyclable, and safe well chamber support under common geological conditions. While ensuring temporary stability, it achieves prefabricated and segmented design, reducing processing and transportation costs and increasing reusability.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is: a recyclable prefabricated steel casing kit, including a steel casing, wherein the steel casing is composed of multiple layers of annular prefabricated steel casings from top to bottom, each layer of prefabricated steel casing is assembled from two or more arc-shaped assemblies and connectors, the arc-shaped assemblies in the same layer are prefabricated and fixedly connected by connectors, and the arc-shaped assemblies in the upper and lower layers are fixed by positioning connecting pieces.

[0005] Preferably, the left and right sides of the arc-shaped assembly are folded inward to form L-shaped flanges, the connector is in the shape of a vertically arranged channel steel, and the flanges of the arc-shaped assembly are fixedly connected to the side plates of the connector by fastening bolts.

[0006] Preferably, the flange and side plate are provided with bolt connection holes that match the fastening bolts, and the bolt connection holes are located at the upper, middle and lower parts of the connection between the flange and the side plate.

[0007] Preferably, the lower part of the connection between the flange and the side plate is provided with three bolt connection holes, which are distributed sequentially from bottom to top at a distance of 30mm from the bottom of the assembled steel casing.

[0008] Preferably, a triangular reinforcing rib is welded between the arc-shaped assembly and the L-shaped flange, and the triangular reinforcing rib is located at the bottom of the assembled steel casing.

[0009] Preferably, the positioning connecting piece is a connecting steel plate. The upper end of the connecting steel plate is fixedly connected to the upper prefabricated steel casing by positioning bolts, and the lower end is welded to the lower prefabricated steel casing. Positioning screw holes matching the positioning bolts are opened on the connecting steel plate and the arc-shaped assembly.

[0010] Preferably, there are four arc-shaped assemblies, which are connected end to end by connectors to form a ring-shaped assembled steel casing.

[0011] Preferably, the bottom of the lowest layer of the assembled steel casing is machined with a cutting edge to facilitate increasing the efficiency of soil layer advance.

[0012] Compared with the prior art, the advantages of this utility model are:

[0013] (1) Safe and reliable: The buckling margin meets the requirements, and the internal support ensures temporary stability;

[0014] (2) High efficiency and speed: modular assembly, combined with manual and mechanical construction, results in high efficiency;

[0015] (3) Recycling: It can be recycled and reused multiple times, reducing costs;

[0016] (4) Economic and environmental protection: Avoids waste from one-time concrete wall protection and reduces carbon emissions;

[0017] (5) High adaptability: Suitable for shallow foundation pit and well construction under soft soil / saturated soil conditions in similar areas. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the assembled steel casing of this utility model;

[0019] Figure 2 This is a top view structural schematic diagram of the assembled steel casing of this utility model;

[0020] Figure 3 This is a schematic diagram of the arc-shaped assembly of this utility model;

[0021] Figure 4 This is a schematic diagram of the assembly structure of the prefabricated steel casing of this utility model;

[0022] Figure 5 This is a schematic diagram of the overall assembly structure of the steel casing of this utility model;

[0023] Figure 6 This is a force-displacement cloud diagram of the assembled steel casing of this utility model.

[0024] In the diagram: 1. Arc-shaped assembly; 11. Flanged edge; 2. Connector; 3. Fastening bolt; 31. Bolt connection hole; 4. Triangular reinforcing rib; 5. Positioning screw hole; 6. Connecting steel plate; 7. Cutting foot. Detailed Implementation

[0025] Example: A recyclable prefabricated steel casing kit, including a steel casing, see [link / reference]. Figures 1 to 5 The steel casing is composed of multiple layers of annular prefabricated steel casings from top to bottom. Each layer of prefabricated steel casing is assembled from two or more arc-shaped assemblies 1 and connectors 2. The arc-shaped assemblies 1 in the same layer are fixedly connected by connectors 2, and the arc-shaped assemblies 1 in the upper and lower layers are fixed by positioning connecting pieces. This utility model adopts a modular design for the steel casing, and each layer of prefabricated steel casing is a split and detachable structure, which can realize the rapid recycling of the steel casing. While ensuring the safety and stability of the well chamber support, it can realize the assembly and segmentation design to reduce processing and transportation costs and improve the reuse rate.

[0026] The steel casing is made of Q235B steel, with a diameter of 2.0m, a section height of 1.0m for each layer, and a wall thickness of 10mm. In this embodiment, the assembled steel casing is divided into four arc-shaped assemblies 1 by cutting a quarter circle. The four arc-shaped assemblies 1 are connected end to end by connectors 2 to form an annular assembled steel casing.

[0027] The assembly adopts a detachable, segmented structure. A steel sleeve is divided into four equal assemblies, and each assembly is connected using 14b channel steel and M16 bolts. Specifically, the cut edges on both sides of the arc-shaped assembly 1 are folded inwards by 60mm to form L-shaped flanges 11, facilitating subsequent assembly with the connector 2. The connector 2 is a vertically arranged channel steel with high structural strength, and its side plates easily align with the flanges 11 of the arc-shaped assembly 1. The flanges 11 of the arc-shaped assembly 1 and the side plates of the connector 2 are fixedly connected using M16 bolts 3.

[0028] The flange 11 and the side plate are provided with bolt connection holes 31 that match the fastening bolts 3. The bolt connection holes 31 are located at the upper, middle and lower parts of the connection between the flange 11 and the side plate. The assembly connection between the arc-shaped assembly 1 and the connector 2 is realized by the fastening bolts 3 and the bolt connection holes 31.

[0029] Static stress structural analysis of the prefabricated steel casing was performed, and its stress-displacement contour diagram is shown below. Figure 6 As can be seen, there is a large displacement at the connection between the arc-shaped assembly 1 and the connector 2 at the bottom of the prefabricated steel casing. To solve this problem, the following design was carried out:

[0030] The flange 11 and the side plate are connected at the lower part of the connection point. The three bolt connection holes 31 are distributed from bottom to top at a distance of 30mm from the bottom of the assembled steel casing. By adding a structural connection point of fastening bolt 3 at the bottom of the connection point, the strength of the connection structure is increased and the displacement is reduced.

[0031] A triangular reinforcing rib 4 is welded between the arc-shaped assembly 1 and the L-shaped flange 11. The triangular reinforcing rib 4 is located at the bottom of the assembled steel casing to increase the structural strength between the flange 11 and the arc-shaped assembly 1 and reduce the combined displacement.

[0032] To ensure the positioning between layers of the steel casing, this utility model incorporates a positioning connecting piece, which is a connecting steel plate 6. The upper end of the connecting steel plate 6 is fixedly connected to the upper prefabricated steel casing via positioning bolts, and the lower end is welded to the lower prefabricated steel casing. The connecting steel plate 6 and the arc-shaped assembly 1 are provided with M16 positioning screw holes 5 that match the positioning bolts. The lower arc-shaped assembly 1 is connected and fixed to the upper arc-shaped assembly 1 via positioning bolts on the connecting steel plate, thereby achieving the connection and positioning between the upper and lower arc-shaped assemblies 1. The connecting steel plate 6 is a 100mm×50mm×10mm rectangular perforated steel sheet. The center of the perforation of the positioning screw hole 5 is 30mm away from one wide side of the steel sheet and located on the center line of the steel sheet. The other side of the unperforated steel sheet has a 40mm length reserved for welding to the lower arc-shaped assembly 1. Through four arc-shaped assemblies 1, a total of four connecting steel plates are designed to achieve the vertical interlayer connection of the steel casing.

[0033] The bottom of the lowest layer of the assembled steel casing, see [reference]. Figure 4 The cutting process using cutting foot 7 is adopted. Specifically, the cutting foot 7 is a trapezoidal cross section with an upper bottom width of 5mm, a lower bottom width of 20mm, and a height of 10mm. The cutting foot 7 is formed by cutting and grinding the bottom of the original steel casing, so that the bottom assembled steel casing can easily cut the soil layer.

[0034] The specific construction and usage process is as follows:

[0035] 1. The site is leveled, laid out, and the prefabricated steel casing is pre-assembled and inspected.

[0036] 2. The steel casing is lowered. During the lowering process, it needs to be installed and welded / bolted layer by layer. At the same time, it is lowered gradually by its own weight and manual excavation. One section of the prefabricated steel casing is lowered every 0.7m. It must be kept aligned with the center line of the pipeline. When encountering soft strata, the lowering can be assisted by water injection, mud wall protection or mechanical static pressure / hydraulic vibration.

[0037] 3. During the sinking process of the steel casing, the verticality and planar position deviation of the casing should be monitored in real time (verticality ≤1%, position deviation ≤30mm). Correction should be carried out by means of hammering, reverse over-excavation, and horizontal thrust of jacks. The sinking speed should be controlled within 0.5m / min to ensure uniform force distribution.

[0038] 4. During the sinking process, the area affected by the casing should be over-excavated by 10% to ensure that the soil pressure on the steel casing is active soil pressure, thereby reducing the risk of pressure.

[0039] 5. The top of the casing should extend above the ground to form a manhole protection ring, with guardrails and safety grilles installed around it. A steel ladder should be installed inside the casing for personnel access, along with fall arrestors, ventilation, and drainage systems to ensure the safety of construction workers.

[0040] 6. Through the design of prefabricated steel casing, the steel casing was allowed to sink in layers, stopping when it reached the designed construction surface, and the main construction of the pipeline well was completed inside the casing.

[0041] 7. When dismantling and recycling the steel casing, since the prefabricated steel casing is a detachable structure, it can be dismantled section by section from bottom to top in reverse. After complete dismantling, check whether the arc-shaped assembly 1 and the connecting parts 2 are deformed. If they meet the deformation safety requirements, they can be transported to the next construction site for reuse.

[0042] The above provides a detailed description of a recyclable prefabricated steel casing kit provided by this utility model. Specific examples have been used to illustrate the principle and implementation of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, based on the idea of ​​this utility model, there will be changes in the specific implementation and application scope. Changes and improvements to this utility model are possible without exceeding the concept and scope specified in the appended claims. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A recyclable prefabricated steel casing kit, comprising a steel casing, characterized in that: The steel casing is composed of multiple layers of annular assembled steel casings from top to bottom. Each layer of assembled steel casing is assembled from arc-shaped assemblies and connectors. The arc-shaped assemblies in the same layer are fixedly connected by connectors, and the arc-shaped assemblies in the upper and lower layers are fixed by positioning connecting pieces.

2. The recyclable prefabricated steel casing kit according to claim 1, characterized in that: The left and right sides of the arc-shaped assembly are folded inward to form L-shaped flanges. The connector is in the shape of a vertically arranged channel steel. The flanges of the arc-shaped assembly and the side plates of the connector are fixedly connected by fastening bolts.

3. A recyclable prefabricated steel casing kit according to claim 2, characterized in that: The flange and side plate are provided with bolt connection holes that match the fastening bolts. The bolt connection holes are located at the upper, middle and lower parts of the connection between the flange and the side plate.

4. A recyclable prefabricated steel casing kit according to claim 3, characterized in that: The lower part of the connection between the flange and the side plate is provided with three bolt connection holes. The three bolt connection holes are distributed sequentially from bottom to top at a distance of 30mm from the bottom of the assembled steel casing.

5. A recyclable prefabricated steel casing kit according to claim 2, characterized in that: A triangular reinforcing rib is welded between the arc-shaped assembly and the L-shaped flange, and the triangular reinforcing rib is located at the bottom of the assembled steel casing.

6. A recyclable prefabricated steel casing kit according to claim 1, characterized in that: The positioning connecting piece is a connecting steel plate. The upper end of the connecting steel plate is fixedly connected to the upper prefabricated steel casing by positioning bolts, and the lower end is welded to the lower prefabricated steel casing. Positioning screw holes matching the positioning bolts are opened on the connecting steel plate and the arc-shaped assembly.

7. A recyclable prefabricated steel casing kit according to claim 1, characterized in that: There are four arc-shaped assemblies, which are connected end to end by connectors to form a ring-shaped assembled steel casing.

8. A recyclable prefabricated steel casing kit according to claim 1, characterized in that: The bottom of the lowest layer of the assembled steel casing is machined with a cutting edge to facilitate increasing the efficiency of soil layer advance.

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