基于破坏模式拟合方法的地下结构爆炸损伤评估

近期地铁、矿井等地下生产和公用设施的安全问题逐渐凸显，爆炸载荷下地下结构的响应和损伤课题是研究这类问题的关键点，其中集合了爆炸载荷、土壤与结构相互作用、和结构非线性动态响应等丰富的力学内涵。以往成果大多使用等效单自由度系统或特定有限元模型，造成计算精度不足或效率偏低，不能满足快速评估损伤的要求。本项目拟研究内部和外部爆炸情形下土壤与结构之间的相互作用机理（SSI），改进经典破坏模式拟合方法，建立地下结构爆炸损伤评估体系。该体系包含结构易损评价图，地下结构单元和整体结构的损伤评估方法，并且可以利用程序根据损伤结果反算爆炸载荷，对评估和设计工作有较高的参考和实用价值。项目中将研究土壤动态密度变化等因素在波传播问题中的特性，针对爆炸载荷提出适用于地下结构的SSI模型，深入探讨边界条件和复合破坏模式对结构损伤的影响，为今后研究地下结构抗爆课题打下坚实的理论基础。

Nowadays,safety issues of underground public facilities, such as subway and mines, become more and more important. Structural response and damage of underground structures under blast load are the key points to solve relative problems, which involves mechanical aspects including blast load, soil-structure interaction, and non-linear dynamic response. Most of previous results were based on equivalent SDOF system or specific FE model, which lead to low accuracy or low efficiency. Such results cannot meet the needs of time-saving damage assessment in such field. The current research project aims to study soil-structure interaction (SSI) under internal and external blast senarios, improve mode approximation method, and build up damage assessment system for underground structure under blast load. The system is based on vulnerability map and will be able to not only assess underground structural element and whole structure, but also back-analyze blast load based on structural damage by using designed software. It is highly valued in assessment and structure design fields.The present project will study effect of density change in wave propagation, build up proper SSI model for blast load and underground structure, and discuss effects of boundary condition and combined failure modes in structural damage. The results will lay a solid foundation for further study.