Construction method of IV-level surrounding rock shotcrete-anchor supporting system of drilling and blasting method tunnel

• Main Authors: LI ZHIJUN, YANG CHAOSHUAI, WANG JINGANG, HONG KAIRONG, LIU YONGSHENG, YIN LONG, CHEN QIAO, ZHOU YI, PAN YUE, YOU JINHU, XIE TAO, ZHANG JICHAO
• Format: Patent
• Language: Chinese; English
• Published: 04.11.2022
• Subjects: EARTH DRILLING; FIXED CONSTRUCTIONS; GALLERIES; LARGE UNDERGROUND CHAMBERS; MINING; SHAFTS; TUNNELS

The invention discloses a construction method of a drilling-blasting method tunnel IV-level surrounding rock shotcrete-anchor support system, which comprises the following steps: S1, after blasting excavation of a section of surrounding rock, in the excavated section, sequentially spraying a layer of steel fiber shotcrete from the left side wall and the right side wall of a tunnel to the upper arch part, and initially setting to form a steel fiber shotcrete layer; s2, anchor rod orifices are formed in the upper portion of the surrounding rock where the steel fiber sprayed concrete is initially set, drilling is conducted to the designed depth, the pre-stressed anchor rods are arranged in the drilled holes, and grouting is conducted in the holes; and S3, in the surrounding rock where the pre-stressed anchor rods are installed, one or two steel fiber sprayed concrete layers are sprayed to the initially-set steel fiber sprayed concrete in the sequence from the left side wall and the right side wall of the tunnel