高水压隧道衬砌渗流-应力-损伤耦合模型研究

Study on Seepage-stress-failure Coupling Model for Tunnel Lining with High Water Pressure

研究目的:富水区隧道衬砌由于长期处在高水压的环境中,衬砌的损伤受到渗流场的影响较为明显,由于渗流场作用而产生相应的应力场和损伤场的变化,衬砌损伤和应力的变化又对渗流场产生反作用,对衬砌结构的混凝土的渗流场、应力场及损伤场进行分析和研究;通过流固耦合来表达隧道衬砌损伤及演化过程,以提高对高水压隧道衬砌损伤表达的准确性和鲁棒性。研究结论:(1)可将混凝土损伤的宏观表达和细观变化统一起来,采用混凝土代表体积单元体作为承水压隧道衬砌流固耦合的研究对象;(2)建立高水压隧道衬砌渗流场、应力场和损伤场的流固耦合模型,采用迭代法可提高模型的可行性;(3)工程计算实例中通过比较是否考虑耦合的情况进行计算模拟衬砌损伤表达,得出流固耦合模型能够更客观的反映实际情况;(4)流固耦合模型能够应用于隧道健康监测及维护。

Research purposes： The seepage field has the distinct impact on the failure of the tunnel lining in the water - rich area due to the long - term high water pressure on the lining. The corresponding changes take place to the failure field and stress field, simultaneously due to the effect of the seepage field while the lining failure and the stress change have reaction on the seepage field. The study was done on the seepage field, stress field and failure field of the concrete of the tunnel lining. The fluid - solid coupling was used to express the failure of the tunnel lining and the evolution process for improving the expression accuracy and robustness of failure of the tunnel lining with high water pressure. Research conclusions： （ 1 ） The macro expression of the concrete failure can be unified with the micro changes and the representative volume element can be used as the study objective of the fluid - solid coupling of the tunnel lining. （2） The fluid -solid coupling model for the seepage field, stress field and failure field of the tunnel lining with high water pressure and the iterative method can be used to enhance the model feasibility. （3） In the calculation of the real construction, the calculation and simulations can be made to express the lining failure on consideration of the situation with the coupling or with no coupling for more objectively reflecting the actual situation by using fluid - solid coupling model. （4） The fluid - solid model is available for the healthy monitoring and maintenance of the tunnel.