Retractable supporting lagging jack

Abstract

The invention relates to the technical field of coal roadway supporting, and discloses a retractable supporting lagging jack which comprises a box-shaped lagging jack body arranged in a disconnected mode and a yielding structure located at the disconnected position of the box-shaped lagging jack body and connected with the box-shaped lagging jack body. The yielding structure comprises a cylindrical yielding main body and a connecting part for connecting the yielding main body and the box-type arch frame; two ends of the same yielding main body are respectively provided with a group of connecting parts; and the yielding main body is manufactured by a cold bending process. The yielding main body manufactured by the cold bending process is arranged on the box type arch frame, and the good ductility of the yielding main body is utilized, so that under the condition that the bearing capacity is guaranteed, the requirement of light weight is met, and the yielding capacity is good.

Description

Technical Field

[0001] The present invention relates to the technical field of coal roadway support, and particularly relates to a collapsible support arch. Background Art

[0002] Among the steel arch frames used for coal roadway support, the support force of the concrete-filled steel tube arch frame is higher than that of the U-shaped arch frame. The joints of the concrete-filled steel tube arch frame are mostly sleeve connections or flange connections, lacking yielding capacity and unable to give full play to the self-bearing capacity of the surrounding rock. The U-shaped steel has yielding capacity, but the U-shaped steel is simple to install but has a large self-weight, resulting in a large construction burden. In this regard, a scheme of using a box-shaped cross-section to replace the U-shaped steel is proposed, which can greatly reduce the steel consumption while ensuring equivalent bearing capacity and achieve the lightweight of the arch frame.

[0003] The existing U-shaped steel realizes yielding by means of lapping, while the box-shaped cross-section cannot be lapped. In addition, the U-shaped steel lapping form is fixed by using clamps, and yielding is achieved by the mutual dislocation and sliding of the lapping joints. However, for this lapping form, the yielding resistance of friction sliding is mainly related to the length of the lapping section and the pre-tightening degree of the clamp bolts. During the on-site construction and installation of the arch frame, the clamp bolts often cannot reach the designed torque value, resulting in the yielding resistance of the arch frame not meeting the design requirements either. And after the arch frame slides, the torque of the clamp bolts will decrease, leading to a further decrease in the support resistance. Therefore, a yielding structure needs to be designed for the box-shaped cross-section arch frame. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a collapsible support arch. By arranging a yielding main body made by cold bending process on the box-shaped arch frame, and using the good ductility of the yielding main body, while ensuring the bearing capacity, the requirements of lightweight are realized, and good yielding capacity is also possessed.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: a collapsible support arch, including a box-shaped arch frame arranged in a disconnected manner, and a yielding structure located at the disconnection of the box-shaped arch frame and connected thereto; The yielding structure includes a cylindrical yielding main body and a connecting component connecting the yielding main body and the box-shaped arch frame; a set of connecting components are respectively arranged at both ends of the same yielding main body; The yielding main body is manufactured by cold bending process.

[0006] Further, the box-shaped arch frame includes a first section arch frame, a second section arch frame and a third section arch frame which are disconnected and arranged in sequence along the arch shape; there are two sets of yielding structures, one set is used to connect the first section arch frame and the second section arch frame, and the other set is used to connect the second section arch frame and the third section arch frame.

[0007] Further, the yielding structure adopts an integral forming process.

[0008] Further, the yielding body includes a cylindrical outer cell, an inner cell located inside the outer cell, and rib plates connecting the outer cell and the inner cell.

[0009] Further, the connecting member includes an end plate fixedly connected to the end of the yielding body, and a sleeve with one end fixedly connected to the end plate; the sleeve is sleeved outside the corresponding box-shaped arch frame, and the cross-sectional shape of the sleeve is adapted to the cross-sectional shape of the box-shaped arch frame.

[0010] Further, base plates are fixedly installed at the bottoms of the two column feet of the box-shaped arch frame.

[0011] Further, the cross-section of the box-shaped arch frame is a closed cross-section, and the cross-sectional shape is rectangular, circular, or trapezoidal.

[0012] The beneficial effects of the present invention are as follows: By arranging a yielding body made by cold bending process on the box-shaped arch frame, and utilizing the good ductility of the yielding body, the requirement of lightweight is achieved while ensuring the bearing capacity. Compared with the existing U-shaped steel, it has better yielding ability. The box-shaped cross-section arch frame is used as the main body, and the upper part of the box-shaped cross-section arch frame is disconnected, and the disconnected part is connected by a yielding structure; the yielding body is a multi-cell cold-formed thin-walled member, and the wall thickness, cross-sectional form, number of rib plates, member height, etc. of the yielding body can be adjusted according to the surrounding rock support requirements, so as to achieve different yielding resistances and yielding strokes. The yielding structure uses metal yielding of cold-formed thin-walled members. By utilizing the characteristic that the steel structure itself has good ductility, the designed yielding structure also has excellent yield bearing capacity, and this joint structure will not be affected by assembly construction and cause changes in yielding performance. Description of the Drawings

[0013] Figure 1 is the overall structure schematic diagram; Figure 2 is the yielding structure schematic diagram; Figure 3 is the yielding body structure schematic diagram In the figure: 1, the first section of the arch frame; 2, the second section of the arch frame; 3, the third section of the arch frame; 4, the yielding body; 401, the outer cell; 402, the inner cell; 403, the rib plate; 5, the end plate; 6, the sleeve; 7, the base plate. Detailed Embodiments

[0014] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0015] The directional terms mentioned in the present invention, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side", "top" and "bottom", etc., are only with reference to the orientation of the attached drawings. The directional terms used are for explaining and understanding the present invention, rather than for limiting the present invention.

[0016] Embodiment: As Figures 1 - 3 shown, a retractable support arch includes a box-shaped arch arranged discontinuously, and a yielding structure located at and connected to the discontinuous part of the box-shaped arch; The yielding structure includes a cylindrical yielding main body 4, and connecting components connecting the yielding main body 4 and the box-shaped arch; a set of connecting components are respectively arranged at both ends of the same yielding main body 4; The yielding main body 4 is manufactured by a cold bending process.

[0017] The box-shaped arch includes a first arch section 1, a second arch section 2 and a third arch section 3 which are arranged discontinuously and in sequence along the arch shape; there are two sets of yielding structures, one set is used to connect the first arch section 1 and the second arch section 2, and the other set is used to connect the second arch section 2 and the third arch section 3; the first arch section 1 is symmetrical with the third arch section 3, and the second arch section 2 is located above the first arch section 1 and the third arch section 3.

[0018] The yielding structure adopts an integral forming process. Using a cold-formed thin-walled steel closed-section yielding main body 4 to replace the lap joint of the traditional U-shaped steel arch, the cross-section form of the yielding main body 4 is diverse, different support yielding curves can be realized, the yielding main body 4 can be directly prefabricated and formed by the factory, the yielding main body 4 has excellent ductility, can yield by using the yield displacement, after the preset yielding stroke ends, the two sections of the arch are in contact, and the support bearing capacity is further improved.

[0019] The yielding main body 4 includes an outer cell 401 in the shape of a cylinder located outside, an inner cell 402 located inside the outer cell 401, and rib plates 403 connecting the outer cell 401 and the inner cell 402; both the outer cell 401 and the inner cell 402 are cylindrical tubes. The multi-cell yielding main body manufactured by the cold bending process realizes yielding by using its excellent ductility, and has the advantages of high applicability, stable yielding resistance and simple construction. The yielding structure is composed of three parts: the cold-formed thin-walled yielding main body 4, end plates 5 and sleeves 6. Different initial peak resistances can be realized by designing the cross-section form of the inner cell 402, different yielding resistances can be realized by designing the number of rib plates 403, and the stable crushing deformation can be realized through the interaction of the outer cell 401, rib plates 403 and the inner cell 402, ensuring stability in the yielding stage; compared with the existing yielding structure, the yielding structure of this solution can maintain a stable bearing capacity even when crushed and can continue to be used.

[0020] The connecting component includes an end plate 5 fixedly connected to the end of the yielding main body 4, and a sleeve 6 with one end fixedly connected to the end plate 5; the sleeve 6 is sleeved outside the corresponding box-shaped arch frame, and the cross-sectional shape of the sleeve 6 is adapted to the cross-sectional shape of the box-shaped arch frame; the end plate 5 ensures the bearing pressure at the end of the arch frame and the connection stability; the cross-sectional dimension of the sleeve 6 is 1-2 mm larger than the corresponding part of the cross-section of the box-shaped arch frame, which is convenient for sleeving; there are four sleeves 6 in total, which are respectively sleeved on the top of the first-section arch frame 1, sleeved on both ends of the second-section arch frame 2, and sleeved on the top of the third-section arch frame 3; one side of the end plate 5 is generally fixed to the yielding main body 4 by welding, and the other side of the end plate 5 is generally also fixed to the end of the sleeve 6 by welding.

[0021] Base plates 7 are fixedly installed at the bottoms of the two column feet located at the bottom of the box-shaped arch frame.

[0022] The cross-section of the box-shaped arch frame is a closed cross-section, which can be rectangular, circular, trapezoidal, polygonal, etc.

[0023] This application uses a box-shaped cross-section arch frame, which can improve the torsional and bending resistance of the cross-section, reduce the steel consumption, and realize the light weight of the arch frame; the bending process of the box-shaped cross-section is mature, such as press bending and roll bending, and an ideal bending effect can also be achieved for arch frames using higher-grade steel. The cross-section wall thickness is small, and the weight of each section of the arch frame is much lighter than that of the U-shaped steel.

[0024] The function of the end plate 5 is to connect the cold-formed thin-wall yielding main body 4 and the sleeve 6 and transfer the load. The setting of the end plate can realize the more uniform conduction of the internal force of the arch frame to the yielding component.

[0025] The design of the sleeve 6 makes the node applicability high. By changing the form of the sleeve 6, the compatibility with different types of steel arch frames can be realized. This yielding structure can be prefabricated and spliced in the factory. Only sleeve installation is required on site, which can reduce the construction steps and improve the node quality. By replacing the sleeve for different arch frame forms, the node substitution can be realized, and the rapidity and flexibility of construction and installation can be achieved.

[0026] The yielding main body 4 is directly preformed in the factory, and its bearing capacity will not be affected by on-site construction operations, resulting in a change in the yielding performance. By designing the cross-sectional form and cross-sectional thickness of the cold-formed thin-wall yielding main body 4, different yield bearing capacities, that is, yielding resistances, can be realized; by designing the height of the yielding main body 4, different yielding strokes can be realized and adjusted according to different roadway surrounding rock conditions; thus, the design of adjustable yielding resistance and stroke is realized.

[0027] The cold-formed thin-wall yielding main body is universal and can provide a stable yielding resistance; by changing the form of the sleeve 6, different types of steel arch frames can be compatible. The sleeve can also be preformed in the factory, which ensures the construction quality and improves the applicability design.

[0028] The above are only used to illustrate the technical solution of the present invention rather than to limit it. Any other modifications or equivalent substitutions made by those of ordinary skill in the art to the technical solution of the present invention shall be covered within the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A retractable support arch, characterized in that: It includes a box-type arch frame that is disconnected, and a pressure-yielding structure that is located at the disconnection point of the box-type arch frame and connected thereto; The pressure-releasing structure comprises a cylindrical pressure-releasing body (4) and a connecting component connecting the pressure-releasing body (4) and the box-shaped arch frame; a group of connecting components are respectively arranged at both ends of the pressure-releasing body (4); The pressure-yielding body (4) is manufactured using a cold bending process.

2. The retractable support arch according to claim 1, characterized in that: The box-shaped arch frame comprises a first arch frame (1), a second arch frame (2) and a third arch frame (3) which are disconnected and arranged in sequence along the arch; the pressure-relieving structures have two groups, one of which is used to connect the first arch frame (1) and the second arch frame (2), and the other is used to connect the second arch frame (2) and the third arch frame (3).

3. The retractable support arch according to claim 1, characterized in that: The pressure-releasing structure adopts an integrated molding process.

4. The retractable support arch according to claim 1, characterized in that: The pressure-releasing body (4) comprises a cylindrical outer cell (401), an inner cell (402) located inside the outer cell (401), and a rib plate (403) connecting the outer cell (401) and the inner cell (402).

5. The retractable support arch according to claim 1, characterized in that: The connecting component comprises an end plate (5) fixedly connected to the end of the pressure-releasing body (4), and a sleeve (6) having one end fixedly connected to the end plate (5); the sleeve (6) is sleeved on the outside of the corresponding box-shaped arch frame, and the cross-sectional shape of the sleeve (6) is adapted to the cross-sectional shape of the box-shaped arch frame.

6. The retractable support arch according to claim 1, characterized in that: Pads (7) are fixedly mounted on the bottoms of the two column feet of the box-shaped arch frame.

7. The retractable support arch according to claim 1, characterized in that: The cross section of the box-type arch frame is a closed cross section, and the cross section shape is rectangular, circular, or trapezoidal.

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