Concrete steel pipe column for gob-side entry retaining in coal mining roadway

Abstract

The utility model belongs to the coal mining roadway field especially concrete steel pipe column of coal mining roadway gob side entry retaining, in view of the existing steel column of mining is hollow column, the insufficient strength, and when the roadway surrounding rock pressure increases abnormally and exceeds its ultimate bearing capacity, the pillar will suddenly fail without any sign, the problem of instantaneous loss of bearing capacity, the present scheme is proposed, it includes the main pipe body and sets up the connecting column in the main pipe body, first cavity and second cavity are equipped in main pipe body and connecting column respectively, first cavity and second cavity are filled with first core column and second core column respectively, still include the pressure relief mechanism for pressure relief, the main pipe body and connecting column are mutually sleeved, and are connected through height adjusting mechanism, to realize the overall height adjustment of column body, the main pipe body and connecting column in the utility model all adopt high strength seamless steel pipe, early strength concrete is poured in, and the compound bearing structure of rigidity and flexibility is formed, and the compression resistance and deformation resistance are improved obviously.

Description

Technical Field

[0001] This utility model relates to the field of coal mining roadway technology, and in particular to concrete steel pipe columns for roadway retention along the goaf in coal mining roadways. Background Technology

[0002] Goaf retention refers to maintaining the original mining roadway along the edge of the goaf after the coal face is mined. To recover the protective coal pillars left in traditional mining methods, certain technical means are used to re-support the roadway from the previous section for use in the next section. This method of retaining roadways along the edge of the goaf at the original roadway location is called goaf retention. Goaf retention can maximize resource recovery, avoid coal loss, reduce surface subsidence and support costs, and improve the stability of the mine ventilation system.

[0003] The steel columns currently used are hollow columns, which lack sufficient strength. Utility Model Content

[0004] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a concrete steel pipe column for leaving roadways along the goaf in coal mining.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The concrete steel pipe column for the goaf retention in the coal mining roadway includes a main body and a connecting column installed in the main body. The main body and the connecting column are respectively provided with a first cavity and a second cavity, and the first cavity and the second cavity are respectively filled with a first core column and a second core column.

[0007] It also includes a pressure relief mechanism for reducing pressure;

[0008] The main body and the connecting column are nested together and connected by a height adjustment mechanism to achieve overall height adjustment of the column.

[0009] In one possible design, the pressure relief mechanism includes a plurality of continuous pressure relief grooves formed in a ring on the lower end of the main pipe, the pressure relief grooves being V-shaped grooves.

[0010] In one possible design, the height adjustment mechanism includes multiple connecting holes formed on the main body and through holes on the connecting column that are adapted to the connecting holes. Fastening bolts are inserted into the connecting holes and through holes, and fixing nuts are threaded onto the fastening bolts.

[0011] In one possible design, both the main pipe and the connecting column are seamless steel pipes, and the wall thickness of the main pipe is 8mm-15mm.

[0012] In one possible design, a base is fixedly provided at the bottom of the main body.

[0013] In one possible design, the base is a square steel plate with an area larger than the cross-sectional area of ​​the main body.

[0014] In one possible design, multiple reinforcing plates are fixedly connected to the base, and each reinforcing plate is fixedly connected to the main body.

[0015] In this application, both the main body and the connecting column are cast with early-strength concrete to form the first core column and the second core column. In the initial stage of installation, the height is adjusted according to the specific height of the roadway roof and floor slabs by the height adjustment mechanism. The connecting column is pulled upward, and then a suitable height connection hole is selected, the fastening bolts are inserted and locked. At this time, the column provides high-strength rigid support through the combined action of the first and second concrete core columns and the steel pipe wall, effectively resisting the roof pressure and controlling the deformation of the surrounding rock.

[0016] When the pressure of the surrounding rock in the roadway increases abnormally and exceeds the rated design bearing capacity of the column (for example, due to strong mining pressure), the column enters the pressure relief protection stage.

[0017] The enormous pressure is transmitted to the main body through the connecting column and bolts. Because a V-shaped pressure relief groove is opened at the lower end of the main body, the cross-section at that point suddenly decreases, forming a highly stress-concentrated area.

[0018] When the stress here exceeds the yield limit of the steel, the pipe wall material at the bottom of the groove begins to undergo plastic flow, the V-groove gradually closes, and the main pipe undergoes slow "necking" deformation in this area.

[0019] This plastic deformation process absorbs a large amount of ground pressure energy, while the overall height of the column will be safely and controllably reduced by a small displacement, thereby releasing some of the surrounding rock stress.

[0020] During the compression process, the internal concrete core column is crushed, but the broken concrete is still constrained inside the steel pipe and works together with the deformed steel pipe to prevent the bearing capacity of the column from suddenly dropping to zero. Instead, it remains stable at a relatively high level of residual support, continuing to provide necessary support for the roadway and preventing the roof from collapsing instantly.

[0021] In this invention, by pre-setting a V-shaped pressure relief groove on the main pressure-bearing pipe body, the failure mode of the support column is transformed from unpredictable and catastrophic sudden fracture to controllable and pre-designed plastic deformation.

[0022] When the pressure in the tunnel exceeds the limit, the pillar absorbs energy through its own deformation, slowly reducing its height while maintaining a high residual support force. This provides valuable early warning time and safety assurance for underground personnel, effectively preventing roof collapse accidents that could be caused by the sudden collapse of the pillar.

[0023] In this utility model, a sleeve-type telescopic structure combined with a bolt-locking adjustment mechanism is used to achieve stepless or graded adjustment of the support height.

[0024] It can flexibly adapt to different mining heights or uneven roof and floor conditions, ensuring that each support can effectively and tightly connect to the roof, so that the entire support system is subjected to uniform stress, which greatly improves the support effect and installation efficiency.

[0025] In this invention, both the main body and the connecting column are made of high-strength seamless steel pipes, with early-strength concrete poured inside to form a composite load-bearing structure that combines rigidity and flexibility, significantly improving the resistance to compression and deformation. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the main structure of the concrete-steel pipe column for the goaf retention in the coal mining roadway proposed in this utility model.

[0027] Figure 2 This is a side view of the concrete-steel pipe column structure for the goaf retention in coal mining roadways proposed in this utility model.

[0028] Figure 3 This is a schematic diagram of the separation structure between the connecting column and the main body of the concrete steel pipe column for the coal mining roadway along the goaf, as proposed in this utility model.

[0029] Figure 4 This is a top view schematic diagram of the concrete-steel pipe column structure for the goaf retention in coal mining roadways proposed in this utility model.

[0030] In the diagram: 1. Base; 2. Main body; 3. Connecting column; 4. First core column; 5. Second core column; 6. Connecting hole; 7. Through hole; 8. Fastening bolt; 9. Fixing nut; 10. Pressure groove; 11. Reinforcing plate. Detailed Implementation

[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0032] In one embodiment, reference is made to... Figure 1-4 The concrete-steel pipe columns used in coal mining roadways include the main pipe 2, connecting column 3, pressure relief mechanism, and height adjustment mechanism.

[0033] The main body 2 is made of high-strength seamless steel pipe with a wall thickness of 8mm to 15mm, which has extremely high initial strength.

[0034] The main body 2 has a first cavity inside, which is filled with a first concrete core column 4; the connecting column 3 has a second cavity inside, which is filled with a second concrete core column 5. These two concrete core columns are preferably early-strength concrete of grade C40 or above, which together with the steel pipe wall form a composite pressure-bearing body with extremely strong compressive strength.

[0035] The connecting post 3 is sleeved in the inner cavity of the main body 2, and the two form a retractable sleeve structure.

[0036] On the wall of the main body 2, multiple sets of connecting holes 6 are opened at intervals along the axial direction. Correspondingly, on the wall of the connecting column 3, a through hole 7 that is adapted to it is opened.

[0037] During installation, the through hole 7 is aligned with a set of selected connecting holes 6 by sliding the connecting column 3 up and down, then the fastening bolt 8 is inserted, and finally the fixing nut 9 is used to lock it, thereby realizing stepless adjustment of the overall height of the column and ensuring that the support can be tightly connected to the top.

[0038] The pressure relief mechanism includes multiple continuous pressure relief grooves 10 annularly formed on the outer wall of the lower end of the main tube 2. The pressure relief grooves 10 are V-shaped grooves formed by precision machining.

[0039] The pressure groove 10 must be positioned below the height adjustment mechanism (i.e., the connecting hole 6 and the fastening bolt 8) and away from the socket area to ensure that the pressure relief occurs in a solid, intact pipe section and does not affect the stability of the upper connection.

[0040] In another embodiment:

[0041] A square base 1 is fixedly welded to the bottom of the main body 2. The area of ​​the base 1 is larger than the cross-sectional area of ​​the main body 2 to effectively distribute the pressure on the bottom plate and prevent it from sinking.

[0042] To further enhance the load-bearing stability of the base 1, multiple triangular reinforcing plates 11 are circumferentially welded at the connection between the base 1 and the main body 2 to form a stable support.

[0043] The accompanying drawings in this application are for illustrative purposes only. The dimensions and shapes of the components shown are not actual limitations but are merely schematic representations. In actual implementation, the components can be reasonably configured and adjusted according to specific needs and actual conditions.

[0044] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A concrete-steel pipe column for a coal mining roadway with goaf retention, comprising a main pipe (2) and a connecting column (3) disposed within the main pipe (2), characterized in that, The main body (2) and the connecting column (3) are respectively provided with a first cavity and a second cavity, and the first cavity and the second cavity are respectively filled with a first core column (4) and a second core column (5); It also includes a pressure relief mechanism for reducing pressure; The main body (2) and the connecting column (3) are nested together and connected by a height adjustment mechanism to achieve overall height adjustment of the column.

2. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 1, characterized in that, The pressure relief mechanism includes a plurality of continuous pressure relief grooves (10) that are annularly formed on the lower end of the main tube (2), and the pressure relief grooves (10) are V-shaped grooves.

3. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 1, characterized in that, The height adjustment mechanism includes multiple connecting holes (6) on the main body (2) and through holes (7) on the connecting column (3) that are adapted to the connecting holes (6). Fastening bolts (8) are inserted in the connecting holes (6) and through holes (7), and fixing nuts (9) are threaded onto the fastening bolts (8).

4. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 1, characterized in that, Both the main tube (2) and the connecting column (3) are seamless steel pipes, and the wall thickness of the main tube (2) is 8mm-15mm.

5. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 1, characterized in that, The bottom of the main body (2) is fixedly provided with a base (1).

6. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 5, characterized in that, The base (1) is a square steel plate with an area larger than the cross-sectional area of ​​the main body (2).

7. The concrete-steel pipe column for leaving the coal mining roadway along the goaf as described in claim 6, characterized in that, Multiple reinforcing plates (11) are fixedly connected to the base (1), and all reinforcing plates (11) are fixedly connected to the main body (2).

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