厦门海底隧道右线穿越F1风化槽施工方案探讨

 厦门翔安海底隧道右线A2标需要穿越F1风化槽段，制定切实可行的穿越F1风化槽段施工方案显得尤其关键。针对该工程施工难度大、工期紧、施工风险大和质量标准高等特点，并结合厦门海底隧道的工程地质特点，制定了穿越F1风化槽段的总体施工技术建议方案，分别从超前地质预报、风化槽段的开挖及支护方案、帷幕注浆、施工排水系统、隧道衬砌施工、突发事件应急处理预案等方面阐述了钻爆法穿越F1风化槽的施工方案与施工注意事项，为工程合理方案的选取奠定基础。

DISCUSSION ON CONSTRUCTION SCHEMES FOR XIAMEN SUBSEA TUNNEL RIGHT LINE CROSSING WEATHERED SLOT F1

In Tender A2 of right line of Xiamen Xiang¢an subsea tunnel，weathered slot F1 is needed to cross through. The feasible tunnel construction scheme to cross F1 weathered slot is important to the subsea tunnel construction. The subsea tunnel project has characteristics of difficult construction，limited construction time，large construction risk and higher construction quality. With consideration of Xiamen Xiang¢an subsea tunnel engineering geology characteristics，the general construction scheme for crossing through weathered slot F1 is proposed. The emphasis is made on the prediction and investigation of engineering geology，the rock mass excavation and lining scheme，the curtain grouting，the construction drainage system，the tunnel lining construction and the preparation scheme. The TSP203 geology prediction method is applied to the approach of the weathered slot F1，which gives guidance to determine the strength parameters of rock mass and underwater pressure. The improved double-side guiding whole tunnel-lining scheme is proposed to replace the original tunnel-lining scheme. Both the advantages and disadvantages of the improved tunnel-lining scheme are discussed. The rock grouting method is used to strengthen the rock mass from water permeation. Grouting schemes for the left and right guided holes，the guidance holes strengthening region and the forward grouting for central hole are discussed. The drainage system is illustrated，and the drainage system location，waterproof strobe are presented. The detailed construction scheme for crossing weathered slot F1 is proposed，which can provide some references to the engineering case.