Controllable supporting structure based on concrete filled steel tube support

Abstract

The utility model relates to the technical field of roadway support, and discloses a yielding and supporting structure based on a concrete-filled steel tube support, which comprises the concrete-filled steel tube support, a sole timber layer, a flexible filling layer, a controllable yielding device, an anchor rod, a pressure relief hole and a yielding steel tube, the concrete-filled steel tube support comprises a steel tube and concrete poured into the steel tube, and reinforcing ribs are arranged on the inner wall of the steel tube. The steel pipe comprises a top steel pipe, a bottom steel pipe, an upper steel pipe and a yielding sleeve; the controllable yielding device comprises a retraction column, a first connecting base and a second connecting base. The pressure relief hole, the controllable yielding device, the yielding sleeve and the flexible filling layer are combined with reinforcement of the ribbed steel pipe and thickening reinforcement of a local weak part, so that yielding and control combined coupling support is realized, and the stability of surrounding rock of a roadway and the stability of a concrete-filled steel tube support are improved; meanwhile, the overload effect of roadway surrounding rock deformation on the concrete-filled steel tube support can be effectively reduced, and the situation that the concrete-filled steel tube support is broken due to local overload is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of roadway support, in particular to a yielding and controlling support structure based on a concrete-filled steel tubular support. Background Technique

[0002] As a key passage for coal mining, ensuring the stability of the surrounding rock of the roadway is a prerequisite for safe production and efficient operation. As the core of strata control, roadway support technology has developed various support technologies such as bolts, cables, grouting reinforcement, steel section supports, shotcrete, and masonry, forming a support system with bolts and cables as the core and multiple support forms used in combination. However, with the depletion of shallow resources and the expansion of coal mining to deep areas, the roadway shows the characteristics of large deformation of soft rock. The traditional bolt-shotcrete support technology and the combined support method of U-shaped steel show problems of limited bearing capacity and unreasonable structural design, and it is difficult to meet the safety and stability requirements of deep roadways.

[0003] To address the challenges faced by deep roadway support, researchers have developed concrete-filled steel tubular supports. The concrete-filled steel tubular support gives full play to the synergy between the steel tube and the concrete. The concrete poured into the steel tube is in a state of all-round compression due to the restraint of the steel tube, which significantly enhances the compressive strength of the concrete, often several times that in the unconstrained state. The combined structure of the steel tube and the concrete effectively blocks the premature bending of the steel tube and significantly improves the rigidity characteristics of the entire structural system.

[0004] However, for deep high-stress and large-deformation soft rock roadways, as a rigid passive bearing structure, the concrete-filled steel tubular support has great rigidity and poor deformation adaptability. When large deformation occurs locally in the surrounding rock of the roadway, it is easy to cause the problem of local overload and fracture of the concrete-filled steel tubular support, affecting the use safety. Content of the Utility Model

[0005] Based on the above problems, the purpose of the utility model is to provide a yielding and controlling support structure based on a concrete-filled steel tubular support to solve the problems existing in the above-mentioned prior art.

[0006] The utility model adopts the following technical solutions:

[0007] The utility model provides a controlled yielding support structure based on a concrete-filled steel tube support, which includes a concrete-filled steel tube support, a cushion wood layer, a flexible filling layer, a controllable pressure relief device, an anchor bolt, a pressure relief hole and a pressure relief steel tube; the concrete-filled steel tube support is arranged inside the surrounding rock of the roadway, the cushion wood layer is arranged between the top of the concrete-filled steel tube support and the surrounding rock, and the flexible filling layer is arranged between the side and bottom of the concrete-filled steel tube support and the surrounding rock; the controllable pressure relief device is arranged between the concrete-filled steel tube support and the surrounding rock, one end of which abuts against the concrete-filled steel tube support, and the other end is connected with the anchor bolt, and the anchor bolt is anchored into the surrounding rock; the pressure relief hole is arranged on the surrounding rock, and the pressure relief steel tube is arranged in the pressure relief hole;

[0008] The concrete-filled steel tube support includes steel tubes arranged in a ring shape and concrete poured inside the steel tubes, and reinforcing ribs are arranged on the inner wall of the steel tubes;

[0009] The steel tubes include a top steel tube, a bottom steel tube, a pressure relief sleeve and side steel tubes, and both ends of the top steel tube and the bottom steel tube are connected to the side steel tubes through the pressure relief sleeves;

[0010] The controllable pressure relief device includes a retraction column, a connecting seat one and a connecting seat two, one end of the retraction column is hinged to the connecting seat one, and the connecting seat one abuts against the steel tube; the other end of the retraction column is hinged to the connecting seat two, and the connecting seat two is connected with the anchor bolt.

[0011] Further, the pressure relief sleeve includes a steel sleeve, and multiple layers of rubber pads are circumferentially connected to the outer wall and the inner wall of the steel sleeve.

[0012] Still further, the reinforcing ribs are integrally formed with the steel tubes, and the reinforcing ribs are closely attached to the inner wall of the steel tubes; the reinforcing ribs can be set as triangular ribs, straight ribs or spiral ribs.

[0013] Still further, a plurality of the concrete-filled steel tube supports are arranged in parallel at intervals, and adjacent concrete-filled steel tube supports are connected by a plurality of top rods.

[0014] Still further, the distance between adjacent concrete-filled steel tube supports is 500 - 1000 mm, and the number of top rods between adjacent concrete-filled steel tube supports is 8 - 12.

[0015] Still further, the cushion wood layer includes multiple groups of laminated wood nailed at intervals.

[0016] Still further, the laminated wood nailed includes multiple wood boards with the same cross-section, and multiple steel nails are vertically nailed into the multiple wood boards.

[0017] Furthermore, the flexible filling layer is formed by stacking multiple woven bags filled with gangue; the concrete poured into the steel pipe is gangue concrete made by using gangue processed into gravel as aggregate.

[0018] Furthermore, the outer diameter of the steel pipe itself is set to 150 - 300 mm, and the wall thickness of the steel pipe is set to 10 - 20 mm; the vulnerable parts of the steel pipe are thickened and strengthened.

[0019] Furthermore, an exhaust and overflow port is provided on the top steel pipe, and a grouting port is provided on the rib steel pipe.

[0020] Compared with the prior art, the beneficial technical effects of the present utility model are as follows:

[0021] By combining the pressure relief holes, controllable yielding devices, yielding sleeves, flexible filling layers with ribbed steel pipes for strengthening, and thickening and strengthening of local weak parts, a coupled support combining yielding and control is achieved, improving the stability of the roadway surrounding rock and the stability of the steel pipe concrete support;

[0022] By installing a yielding steel pipe in the pressure relief hole and regulating the strength of the yielding steel pipe, controlled pressure relief can be achieved; by regulating the yielding load of the retraction column, the effect of yielding and retraction can be achieved. Cooperating with the provided flexible filling layer and yielding steel pipe, it can effectively reduce the overloading effect of the deformation of the roadway surrounding rock on the steel pipe concrete support, avoid the breakage of the steel pipe concrete support due to local overloading, and improve the use safety;

[0023] Through the design of the ribbed steel pipe of the steel pipe concrete support in the mine roadway, not only the compressive and flexural resistance of the steel pipe itself is improved, but also the bond strength between the steel pipe and the concrete is significantly enhanced, strengthening the integrity of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The following further describes the present utility model with reference to the drawings.

[0025] Figure 1 It is a sectional view of the yielding and control support structure based on the steel pipe concrete support of the present utility model;

[0026] Figure 2 It is a three - dimensional structure schematic diagram of the controllable yielding device of the present utility model;

[0027] Figure 3 It is a three - dimensional structure schematic diagram of the steel pipe of the present utility model;

[0028] Figure 4 It is an internal structure schematic diagram of the yielding sleeve of the present utility model;

[0029] Figure 5 It is a three - dimensional structure schematic diagram of the triangular rib of the present utility model;

[0030] Figure 6 Schematic three-dimensional structure diagram of the straight rib of the present utility model;

[0031] Figure 7 Schematic three-dimensional structure diagram of the spiral rib of the present utility model;

[0032] Figure 8 Schematic three-dimensional structure diagram of the laminated nailed wood of the present utility model.

[0033] Explanation of reference numerals: 1, concrete-filled steel tube support; 11, steel tube; 111, top steel tube; 112, bottom steel tube; 113, yielding sleeve; 1131, steel sleeve; 1132, rubber pad; 114, side steel tube; 115, exhaust and overflow port; 116, grouting port; 117, triangular rib; 118, straight rib; 119, spiral rib; 12, concrete; 2, cushion wood layer; 21, laminated nailed wood; 22, steel nail; 3, flexible filling layer; 4, controllable yielding device; 41, retraction column; 42, connecting seat one; 421, arc groove; 43, connecting seat two; 44, pin head; 45, pin shaft; 5, bolt; 6, pressure relief hole; 7, yielding steel tube; 8, ejector rod. Detailed implementation manners

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0035] As Figures 1 - 8 shown, in this embodiment, a controllable support structure based on a concrete-filled steel tube support is disclosed, which includes a concrete-filled steel tube support 1, a cushion wood layer 2, a flexible filling layer 3, a controllable yielding device 4, a bolt 5, a pressure relief hole 6 and a yielding steel tube 7; the concrete-filled steel tube support 1 is arranged inside the surrounding rock of the roadway, the cushion wood layer 2 is arranged between the top of the concrete-filled steel tube support 1 and the surrounding rock, and the flexible filling layer 3 is arranged between the side and bottom of the concrete-filled steel tube support 1 and the surrounding rock; the controllable yielding device 4 is arranged between the concrete-filled steel tube support 1 and the surrounding rock, one end of which abuts against the concrete-filled steel tube support 1 and the other end is connected to the bolt 5, and the bolt 5 is anchored into the surrounding rock; the pressure relief hole 6 is arranged on the surrounding rock, and the yielding steel tube 7 is arranged in the pressure relief hole 6;

[0036] The concrete-filled steel tube support 1 includes a steel tube 11 arranged in a ring shape and concrete 12 poured inside the steel tube 11, and reinforcing ribs are arranged on the inner wall of the steel tube 11;

[0037] The steel tube 11 includes a top steel tube 111, a bottom steel tube 112, a yielding sleeve 113 and a side steel tube 114, and both ends of the top steel tube 111 and the bottom steel tube 112 are connected to the side steel tube 114 through the yielding sleeve 113;

[0038] The controllable yielding pressure regulator 4 includes a retraction column 41, a first connecting seat 42 and a second connecting seat 43. One end of the retraction column 41 is hinged to the first connecting seat 42, and the first connecting seat 42 abuts against the steel pipe 11; the other end of the retraction column 41 is hinged to the second connecting seat 43, and the second connecting seat 43 is connected to the bolt 5.

[0039] In this embodiment, the diameter of the pressure relief hole 6 is set to 100 - 300 mm, the length of the pressure relief hole 6 is set to 5 - 12 m, and the spacing between adjacent pressure relief holes 6 is set to 300 - 1000 mm; the pressure relief hole 6 can be arranged at the top, side and bottom of the roadway, and the number, position and length of the pressure relief hole 6 can be adjusted according to the abutment pressure, roadway deformation amount, etc.

[0040] The controllable yielding pressure regulator 4 can play a role in buffering and pressure relief. The controllable yielding pressure regulator 4 is installed at a position with a large roadway deformation amount, and its yielding load, yielding displacement amount, number and position can be adjusted according to specific conditions; an arc-shaped groove 421 is provided on the first connecting seat 42, and the first connecting seat 42 abuts against the steel pipe concrete support 1 through the arc-shaped groove 421; the first connecting seat 42 and the second connecting seat 43 are respectively hinged to both ends of the retraction column 41 through a pin head 44 and a pin shaft 45; the retraction column 41 is set as an internal injection type single hydraulic prop or an external injection type single hydraulic prop. The maximum yielding displacement amount of the retraction column 41 has various specifications such as 50 mm, 100 mm, 150 mm, 200 mm, etc.

[0041] The top steel pipe 111, the bottom steel pipe 112 and the side steel pipe 114 are all bent to form an arc-shaped structure, and their radii and lengths can be selected according to the roadway section shape and size; reinforcing ribs are provided on the inner wall of the steel pipe 11 to form a ribbed steel pipe.

[0042] The concrete 12 poured into the steel pipe 11 is set as gangue concrete, and the aggregate selected in the gangue concrete is the relatively strong gangue discharged during roadway tunneling or repair. After processing the gangue into crushed stones, 20% to 30% of the common aggregate is replaced to make high-strength gangue concrete.

[0043] The flexible filling layer 3 is stacked by a plurality of woven bags filled with gangue. For the gangue discharged during roadway tunneling or repair, a part of the relatively strong gangue is used as the aggregate of the gangue concrete, and the remaining gangue is respectively filled into a plurality of woven bags to be used as the filler of the flexible filling layer 3; in this way, not only can resources be reasonably utilized, but also an environmental protection effect can be achieved.

[0044] Adopting this scheme, through the combination of the pressure relief hole 6, the controllable yielding pressure regulator 4, the yielding sleeve 113, the flexible filling layer 3 and the strengthening of the ribbed steel pipe and the local weak part thickening and strengthening, the coupling support of yielding and control is realized, and the stability of the roadway surrounding rock and the steel pipe concrete support 1 is improved;

[0045] By installing a pressure-relieving steel pipe 7 in the pressure-relieving hole 6 and regulating the strength of the pressure-relieving steel pipe 7, controlled pressure relief can be achieved; by regulating the pressure-relieving load of the retractable column 41, the effect of pressure-relieving retraction can be achieved. Cooperating with the set flexible filling layer 3 and the pressure-relieving steel pipe 7, it can effectively reduce the overloading effect of roadway surrounding rock deformation on the concrete-filled steel tubular support 1, avoid the breakage of the concrete-filled steel tubular support 1 due to local overloading, and improve the safety in use.

[0046] Through the ribbed steel pipe design of the concrete-filled steel tubular support 1 for mine roadways, not only the compressive and flexural resistance of the steel pipe itself is improved, but also the bond strength between the steel pipe and the concrete is significantly enhanced, and the integrity of the structure is strengthened.

[0047] In a further optimized scheme, the pressure-relieving sleeve 113 includes a steel sleeve 1131, and multiple layers of rubber pads 1132 are fixedly connected to the outer wall and the inner wall of the steel sleeve 1131 along the circumferential direction.

[0048] In this embodiment, the steel sleeve 1131 is made of high-strength steel pipe with a relatively large thickness, and the rubber pads 1132 on its outer wall and inner wall are both set to one layer, and the rubber pads 1132 are made of phenyl silicone rubber pads. Through the set steel sleeve 1131 and rubber pads 1132, the flexible connection between the top steel pipe 111 and the side steel pipe 114, and between the bottom steel pipe 112 and the side steel pipe 114 is realized; through the pressure-relieving sleeve 113, part of the surrounding rock deformation is absorbed, the pressure generated by the roadway surrounding rock deformation on the concrete-filled steel tubular support 1 is reduced, and the breakage of the concrete-filled steel tubular support 1 at the sleeve is avoided.

[0049] In a further optimized scheme, a plurality of concrete-filled steel tubular supports 1 are provided, and the plurality of concrete-filled steel tubular supports 1 are arranged in parallel at intervals, and adjacent concrete-filled steel tubular supports 1 are connected by a plurality of top rods 8.

[0050] Specifically, the distance between adjacent concrete-filled steel tubular supports 1 is 500 - 1000 mm, and the number of top rods 8 between adjacent concrete-filled steel tubular supports 1 is 8 - 12. The plurality of concrete-filled steel tubular supports 1 are connected into a whole through the set plurality of top rods 8.

[0051] In this embodiment, the top steel pipe 111, the bottom steel pipe 112, and the side steel pipe 114 are all bent into an arc structure, and their radii and lengths can be selected according to the shape and size of the roadway section; the outer diameter of the steel pipe 11 itself is set to 150 - 300 mm, and the wall thickness of the steel pipe 11 is set to 10 - 20 mm; the easily damaged parts of the steel pipe 11 are thickened and strengthened, such as: the grouting port 116, the exhaust and overflow port 115, and the steel pipe near the shoulder angle sleeve.

[0052] For a further optimized solution, an exhaust and overflow port 115 is provided on the top steel pipe 111, and a grouting port 116 is provided on the rib steel pipe 114. Through the provided grouting port 116, gangue concrete can be poured into the steel pipe 11, and through the exhaust and overflow port 115, the air inside the steel pipe 11 can be discharged.

[0053] For a further optimized solution, the reinforcing ribs are integrally formed with the steel pipe 11, and the reinforcing ribs are closely attached to the inner wall of the steel pipe 11; the reinforcing ribs can be set as triangular ribs 117, straight ribs 118 or spiral ribs 119.

[0054] In this embodiment, the number of triangular ribs 117 or straight ribs 118 in each steel pipe 11 can be set to 6 - 12; the triangular ribs 117 are set as equilateral angle steels, the straight ribs 118 are set as straight plate steels, and the spiral ribs 119 are spirally arranged along the inner wall of the steel pipe 11.

[0055] For a further optimized solution, the cushion wood layer 2 includes multiple groups of laminated nailed woods 21 arranged at intervals.

[0056] Specifically, the laminated nailed wood 21 includes multiple wooden boards with the same cross-section. Multiple steel nails 22 are vertically nailed into the wooden boards. The material of the wooden boards, the specifications and spacing of the steel nails 22 can be adjusted according to the actual mine pressure manifestation. The laminated nailed wood 21 has the advantages of high strength, good toughness and not being easily broken, and can better evenly distribute the surrounding rock pressure load borne by the steel pipe concrete support 1, avoiding the load stress concentration of the steel pipe concrete support 1 caused by the breakage of the cushion wood layer 2.

[0057] The utility model includes the following implementation steps:

[0058] Step 1. Preparation of materials: According to the geomechanical characteristics of the roadway surrounding rock, the shape and size of the roadway cross-section, and the mining and excavation engineering technical conditions, determine the parameters of the roadway surrounding rock pressure relief holes 6, yielding steel pipes 7, steel pipe concrete supports 1, controllable yielders 4, cushion wood layers 2 and flexible filling layers 3, and prepare all materials.

[0059] Step 2. Processing of the ribbed steel pipe: According to the shape and size of the roadway cross-section, the mechanical characteristics of the surrounding rock, and the mine pressure manifestation, determine the parameters such as the steel pipe curvature, the type of reinforcing ribs, the width and quantity of the reinforcing ribs, and then process and manufacture the corresponding steel pipes 11.

[0060] Step 3. Processing of the controllable yielder 4: According to the yielding load and yielding displacement of the controllable yielder 4, select a matching retraction column 41. According to the specifications of the steel pipe 11, anchor bolts 5 and other parameters, process the connecting seat one 42, connecting seat two 43, pin head 44 and pin shaft 45, and assemble the above components.

[0061] Step 4. Processing of the laminated nailed wood 21: Vertically embed multiple wooden boards into the board surface with steel nails 22 according to the preset nail spacing to make each board closely connected.

[0062] Step Five, Overall Assembly: When the roadway is excavated or repaired, high-strength anchor mesh cable support shall be carried out in a timely manner; after the anchor mesh cable support, relief holes 6 shall be drilled in the high-stress area and yielding steel pipes 7 shall be installed in the relief holes 6. Then, the bolts 5 shall be anchored into the surrounding rock and fixed to the end of the connecting seat two 43 of the controllable yielding device 4; after the controllable yielding device 4 is fixed, the bottom and sides of the roadway shall be filled with woven bags filled with gangue, and the laminated nailed wood 21 shall be installed at the top of the roadway; after the laminated nailed wood 21 is installed, the top steel pipe 111, the bottom steel pipe 112 and the side steel pipe 114 shall be connected through the yielding sleeve 113, and the retraction column 41 shall be loaded by injecting liquid to make the connecting seat one 42 tightly press against the steel pipe concrete support 1.

[0063] Step Six, Pouring Concrete 12: Pour gangue concrete through the grouting port 116. Stop pouring when a certain amount of concrete slurry flows out of the exhaust overflow port 115 of the top steel pipe 111, and seal the grouting port 116.

[0064] Step Seven, Filling and Hardening of Floor Gangue: To facilitate pedestrian passage and underground transportation requirements, the gangue generated from repair and enlargement shall be bagged and filled, and a concrete floor shall be laid to the designed floor height.

[0065] The above embodiments are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A yielding support structure based on a steel tube concrete support, characterized in that: The invention comprises a steel tube concrete support (1), a cushion layer (2), a flexible filling layer (3), a controllable pressure relief device (4), an anchor rod (5), a pressure relief hole (6) and a pressure relief steel pipe (7); the steel tube concrete support (1) is arranged on the inner side of the tunnel surrounding rock, the cushion layer (2) is arranged between the top of the steel tube concrete support (1) and the surrounding rock, and the flexible filling layer (3) is arranged between the side and bottom of the steel tube concrete support (1) and the surrounding rock; the controllable pressure relief device (4) is arranged between the steel tube concrete support (1) and the surrounding rock, one end of which is against the steel tube concrete support (1) and the other end is connected to the anchor rod (5), and the anchor rod (5) is anchored in the surrounding rock; the pressure relief hole (6) is arranged on the surrounding rock, and the pressure relief steel pipe (7) is arranged in the pressure relief hole (6); The steel tube concrete support (1) comprises steel tubes (11) arranged in an annular shape and concrete (12) poured into the interior of the steel tubes (11); the inner wall of the steel tubes (11) is provided with reinforcing ribs; The steel pipe (11) comprises a top steel pipe (111), a bottom steel pipe (112), a pressure-releasing sleeve (113) and a side steel pipe (114); both ends of the top steel pipe (111) and the bottom steel pipe (112) are connected to the side steel pipe (114) through the pressure-releasing sleeve (113); The controllable pressure relief device (4) comprises a retractable column (41), a connecting seat 1 (42) and a connecting seat 2 (43); one end of the retractable column (41) is hinged to the connecting seat 1 (42), and the connecting seat 1 (42) is against the steel pipe (11); the other end of the retractable column (41) is hinged to the connecting seat 2 (43), and the connecting seat 2 (43) is connected to the anchor rod (5).

2. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The pressure-releasing sleeve (113) comprises a steel sleeve (1131), and the outer wall and the inner wall of the steel sleeve (1131) are connected with multiple layers of rubber pads (1132) along the circumferential direction.

3. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The reinforcing rib is integrally formed with the steel pipe (11), and the reinforcing rib is in close contact with the inner wall of the steel pipe (11); the reinforcing rib can be configured as a triangular rib (117), a straight rib (118) or a spiral rib (119).

4. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: A plurality of the steel tube concrete supports (1) are provided, the plurality of the steel tube concrete supports (1) are arranged in parallel and at intervals, and adjacent steel tube concrete supports (1) are connected via a plurality of top rods (8).

5. The yielding support structure based on steel tube concrete support according to claim 4 is characterized in that: The spacing between adjacent concrete-filled steel tube supports (1) is 500 to 1000 mm, and the number of top rods (8) between adjacent concrete-filled steel tube supports (1) is 8 to 12.

6. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The cushion wood layer (2) comprises a plurality of groups of intermittently arranged plywood nailed together (21).

7. The yielding support structure based on steel tube concrete support according to claim 6 is characterized in that: The laminated wood (21) comprises a plurality of wooden boards with the same cross-section, and a plurality of steel nails (22) are vertically nailed into the plurality of wooden boards.

8. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The flexible filling layer (3) is formed by stacking a plurality of woven bags filled with gangue; the concrete (12) poured into the steel pipe (11) is gangue concrete made by using crushed stone processed from gangue as aggregate.

9. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The outer diameter of the steel pipe (11) itself is set to 150-300 mm, and the wall thickness of the steel pipe (11) is set to 10-20 mm; the vulnerable parts of the steel pipe (11) are thickened and strengthened.

10. The yielding support structure based on steel tube concrete support according to claim 1 is characterized in that: The top steel pipe (111) is provided with an exhaust overflow port (115), and the side steel pipe (114) is provided with a grouting port (116).

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