Abstract Affected by the intersection of two regional faults and a water-resistant rock wall induced by magmatic intrusion, various unfavorable geological bodies may exist in front of the working face at FK18+330 on the left line of the Lingjiao tunnel. In light of these complicated geological conditions, a macroscopic tunnel geological prediction was first conducted on the basis of geological analysis, and then an in-situ geological detection was conducted inside and outside of the tunnel by the following methods respectively: land sonar+transient electromagnetic+geological radar and land sonar+differential electrical sounding+transient electromagnetic. Additionally, a comprehensive analysis and prediction was carried out, with the in-situ excavation results showing that the above comprehensive prediction method can effectively reduce the error of in-situ geophysical prospecting in the tunnel's axial and transverse directions as well as precisely determine the location, size and type of the unfavorable geological bodies in front of the tunnel face under complicated geological conditions.
Abstract：
Affected by the intersection of two regional faults and a water-resistant rock wall induced by magmatic intrusion, various unfavorable geological bodies may exist in front of the working face at FK18+330 on the left line of the Lingjiao tunnel. In light of these complicated geological conditions, a macroscopic tunnel geological prediction was first conducted on the basis of geological analysis, and then an in-situ geological detection was conducted inside and outside of the tunnel by the following methods respectively: land sonar+transient electromagnetic+geological radar and land sonar+differential electrical sounding+transient electromagnetic. Additionally, a comprehensive analysis and prediction was carried out, with the in-situ excavation results showing that the above comprehensive prediction method can effectively reduce the error of in-situ geophysical prospecting in the tunnel's axial and transverse directions as well as precisely determine the location, size and type of the unfavorable geological bodies in front of the tunnel face under complicated geological conditions.
2015, Vol. 52 