双圆盾构隧道衬砌结构受力解析

应用不均衡力矩及侧力、竖力传播法推导了双圆DOT盾构隧道衬砌内力的解析解。结合具体工程实例计算,与同一工况下的数值模拟和现场试验实测数据进行了对比分析。结果表明:解析解的计算结果稍微偏大,数值解最小,而实测值基本是介于二者之间,但三者所反映的内力变化规律基本上是一致的,验证了所推导的解析解的合理性和可靠性。此外,基于解析解分析了双圆盾构隧道衬砌结构计算中各种设计参数对计算结果的敏感性,研究表明:对于中浅埋双圆盾构隧道,拱背土压力的影响不能忽略;并建议将侧向土体抗力系数取为2500～6500 kN/m3,以充分发挥地层的被动抗力作用;在考虑结构受力和合理利用、优化结构断面的基础上,张开角应在30°⁶0°取值。

Internal forces of DOT shield-driven tunnel lining

An analytical solution for the calculation of internal forces of a jointed segmental precast DOT（Double-O-Tube） lining based on the unbalanced forces transition method was presented.With the calculation of a practical project,the numerical simulation method and some data from field measurements were both used to compare and analyze the internal forces of DOT lining.It was shown that the internal forces obtained by analytical solution were the largest,the internal forces obtained by numerical simulation were the smallest and the measured values were in the middle.However,the distributions of internal forces obtained by three different methods well agreed with each other,which demonstrated that the analytical solution was reasonable and reliable.The sensitivities of the design parameters to the distribution of internal forces of DOT lining structure were analyzed,and it was shown that the shoulder ground pressure played an important role to the distribution of internal forces and should not be neglected and the soil resistance coefficient can be chosen between 2500 kN/ m3 and 6500 kN/ m3 in order to activate the soil resistance fully.With respect to the reasonable design and optimization of the cross-section as well as the consideration of the safety factors,the opening angle α should be chosen between30 60 degrees.