Enlarged shape memory alloy anchor rod and anchoring construction process thereof

Abstract

The invention provides an enlarged shape memory alloy anchor rod and an anchoring construction process thereof. An anchor rod supporting structure of the anchor rod comprises a rod body and a rock and earth mass. A bearing table structure is arranged at the end of the rod body. The end of the rod body is sleeved with an annular shape memory alloy component. The rod body and the annular shape memory alloy component are combined and connected through a bearing table to form an integrated shape memory alloy anchor rod body. A predrilled hole is formed in the rock and earth mass, the shape memory alloy anchor rod body is inserted in the predrilled hole, and the shape memory alloy anchor rod body composed of the shape memory alloy component with complete shape memory recovery is locked through a building, a fastener, a carrying board and a table seat. The key construction process includes the steps that the annular shape memory alloy component is manufactured, so that the shape memory alloy anchor rod body, a cylindrical alloy anchor rod anchoring system and an enlarged alloy anchor rod system are formed, and finally an enlarged alloy anchor rod anchoring structure is obtained. By the adoption of the enlarged shape memory alloy anchor rod and the anchoring construction process, the anchoring force (pulling resistance) and the durability of the anchor rod structure can be improved, the application range of the anchor rod structure can be enlarged, the purpose of supporting the rock and earth mass is achieved, the construction process is simple, operation is convenient, and the effect is safe and reliable.

Description

technical field [0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to an enlarged shape memory alloy bolt and its anchoring construction technology. Background technique [0002] The bolt support structure is a new type of tension member system, which tightly connects the sliding rock-soil mass and the stable rock-soil mass through the bolt, greatly increasing the anti-sliding force of each layer of the rock-soil mass, and at the same time, the The upper frame beam effectively connects each anchor rod into a larger whole, forming a reinforcement system from the outside to the inside, and then achieves the purpose of preventing the overall slope from destabilizing. It is an effective anti-slip anchoring structure. Therefore, the bolt support structure has been widely used in loose soil or rock slopes, foundation pits, mines, underground engineering, dams, waterways, reservoirs, tunnels and anti-tilting, anti-floating str...

AI Technical Summary

Problems solved by technology

[0003] As an important parameter of the bolt support structure, the key indicators such as the applied prestress, pull-out force (holding force and shear force), length of the free section and length of the anchor section have always been four difficulties in the field of engineering technology. , if the applied prestress loss is too much, it will be difficult for the anchored rock and soil layer to obtain high enough anti-sliding force or shear strength, so that the support and anchoring effect will be greatly reduced; The safety of the soil cannot be improved; if the length of the free section of the anchor is too short, the more the prestress loss will be, the more unstable the tension of the anchor will be, which will weaken the effect of anchoring; if the length of the anchorage section of the anchor is too short , the pull-out force provided by it will decrease, the tensile force borne by the bolt will decrease, and the possibility of being pulled out will increase, so that the support safety of rock and soil mass cannot be guaranteed.

[0004] Traditional bolt support structures mainly include cylindrical bolts, end-enlarged bolts and continuous spherical bolts. These structures all have some defects or deficiencies in anchoring. The anchorage length, so the prestress loss of the anchor rod during work is relatively large, and it is also required that the tie rod and its surrounding cement mortar have a certain grip force limit, otherwise, the anchor rod cannot provide sufficient pull-out resistance; on the other hand, During the drilling construction process of the traditional bolt support structure, the diameter of the required borehole is relatively large. Therefore, relatively speaking, the soil around the borehole is disturbed more, which changes the distribution of the original stress field and increases the In addition, with the increase of the diameter of the borehole, the cost of the project also increases greatly. The cost of drilling during construction generally accounts for more than 30% of the total cost, and sometimes even exceeds 50%. If the cost of grouting is added, the cost of the project will be even higher

From this point of view, these shortcomings directly affect the bearing capacity of rock and soil bolts, construction efficiency and the cost of the entire support project.

Therefore, for the construction technology adopted by the traditional bolt support structure, it is difficult to simultaneously achieve the advantages of small prestress loss, short anchoring section length, or even no anchoring section, small drilling, and wide application range.

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