基于Mohr-Coulomb准则寒区隧道围岩应力弹塑性解析

随着西部开发建设速度的急剧增长,寒区隧道工程建设逐渐增多,冻胀力及围岩应力大小对寒区隧道结构产生的影响越来越突出。针对这一突出问题,基于弹性理论拉密解及复变理论,结合Mohr-Coulomb屈服准则,确定了围岩塑性区范围,并推导了冻胀力及围岩应力的弹塑性显式解析解。通过算例分析得到:当0°≤θ≤45°时,冻胀力的存在致使围岩塑性区迅速扩展;而当45°≤θ≤90°时,冻胀力的存在却限制了围岩塑性区的发展。其研究成果对寒区隧道工程建设具有良好的参考价值。

Analytical Elasto-plastic Solution for Stress of Surrounding Rock Based on Mohr-Coulomb Criterion

With the rapid growth of the construction of western development, the construction of tunnel engineering in cold region gradually increased, the effect of frost heaving force and stress of surrounding rock on tunnel structures in cold regions is more and more outstanding. In order to solve this problem, based on elastic theory lame solution and complex variable theory and Mohr-Coulomb yield criterion to determine the surrounding rock plastic zone scope, and the elasto-plastic explicit analytical solutions for frost heaving force and stress of surrounding rock were deduced. The results show that, the frost heaving force makes the plastic zone of surrounding rock the rapid expansion when 0°≤θ≤45°. Contrary, the frost heaving force can limit the development of plastic zone of surrounding rock when 45°≤θ≤90°. The research results have a good reference value for the construction of tunnel engineering in cold region.