双连拱隧道施工偏压力学特性的监测与分析研究

Site monitoring and analytical research on mechanical characteristics under construction partial press in double-arch tunnel

结合宜(宾)-水(富)高速公路鞋底坡双连拱隧道工程,通过埋设量测元件对隧道结构受力的关键部位进行现场监控测试与分析,获得了隧道支护结构在施工偏压条件下各施工阶段的围岩应力、锚杆轴力、中墙内力以及隧道支护结构中的内力变化情况。通过对比分析得出:最不利于隧道结构受力(关键是中墙受力)的施工工序发生在隧道由单侧施工过度到双侧施工时;中墙弯矩的方向一般是由后施工洞室向先施工洞室偏转。现场测试所得的数据和结论可望为同类隧道的设计、施工和研究提供有益的借鉴和参考。

According to the Xiedipo double-arch tunnel engineering of the Yishui（Yibin-Shuifu） Highway, the key parts of structure force are monitored and analyzed by setting testing component in the tunnel; and during each period of construction the stress state of surrounding rock, bolt axial force, internal force of the middle-wall and internal forces of tunnel supporting structure are obtained under the condition of the constructional partial press. By analyzing tunnel mechanical characteristic under constructional partial press, the conclusions are drawn as follows; the most dangerous construction procedure of the tunnel structure force is from one side to the other side in the construction of the tunnel, that the bending moment direction of the middle-wall is always from one tunnel constructed lastly to the other tunnel constructed firstly in the double-arch tunnel. The monitored data and the experience can be for reference in the design, construction and research of similar tunnels.