Dynamic mechanical characteristics and engineering application of high elongation anchor cable

The traditional anchor cable has low elongation, poor impact resistance, and is prone to brittle fracture failure under strong impact load, leading to roof fall, rock burst accidents and other problems in the roadway. Based on this, the anchor cable with high strength, high elongation and high impact resistance was independently developed. The static and dynamic mechanical properties of the anchor cable with high elongation were analyzed by laboratory tests, theoretical analysis and field tests. The differences between high elongation anchor cable and ordinary anchor cable in chemical composition, metallographic structure and inclusion are also studied. Finally, the energy absorption principle of high elongation anchor cable support is proposed, and the high elongation anchor cable is applied in the field. The results show that: Under static load, the tensile strength of high elongation anchor cable is 1790 MPa, the total elongation of maximum force is 8.1%, which is 1.61−2.25 times of that of ordinary anchor cable. Under dynamic load, the steel wire of high elongation anchor cable is not easy to disperse, and the breaking load is basically the same as that of ordinary anchor cable. The elongation after breaking is 1.82 times, 1.68 times and 1.52 times of that of anchor cable A, B and C, respectively. The energy absorption per unit length is 2.54 times, 1.99 times and 1.70 times of that of anchor cable A, B and C, respectively. The high elongation anchor cable has stronger plastic deformation capacity and higher energy absorption capacity. The high elongation anchor cable improves the plastic deformation ability of the steel wire by controlling the content of harmful and beneficial chemical elements, refining the metallographic structure and reducing the size and quantity of inclusions in the smelting and rolling process, thereby improving the overall impact resistance of the anchor cable. After the high elongation anchor cable has withstood many large energy shocks in the field application process, the roadway support effect is good, and the high elongation anchor cable has not broken, effectively controlling the roadway impact damage.