Study on Non-blasting Construction Technology of Expansive Agent in Shallow Section of Yushe Tunnel

The shallow-buried section of the Yushe Tunnel has poor integrity of surrounding rocks and is extremely prone to collapse hazards, especially in surface rivers with perennial open water, which is difficult and dangerous for construction. Based on this, this article analyzes the possible risks in the excavation construction, and from the perspectives of safety, environmental protection, and economy, in order to ensure the stability of the tunnel body after excavation, the expansion agent is used for non-blasting in the shallow buried section. A three-step excavation method combining excavation and conventional drilling and blasting. Practice has proved that combined with effective measures, it can smoothly pass the construction of the shallow buried section.