爆炸及地震作用下双层钢箱—混凝土组合墩柱动力灾变性能研究

The bridge structures exposed to the natural environment in long time inevitably encounter multi-hazard loading, such as earthquake, typhoon, tsunamis and other natural disasters, as well as impact, fire, blast and other man-made accident actions, and may result in significant damage of bridge, and the losses of life and property without consideration of multi-hazard loading during life time. In this project, the concrete-filled double skin steel box piers (CFDSBP) are selected as the study objects, the dynamic disaster performance of CFDSBP under the blast loading will be paid more attentions using testing, numerical simulation and theoretical analysis, where the effects of earthquake damage are included. The main study contents are listed as follows: The blast load model of this kinds of composite piers, as well as dynamic damage constitutive model of concrete-filled steel tube will be firstly explored to provide basic support of the dynamic response analysis of DSCFBP. Secondly, the damage failure criterion of CFDSBP will be proposed based on the study on the dynamic damage mechanism and failure modes of CFDSBP under blast and earthquake loading. Finally, the simplified analysis method of the dynamic response of CFDSBP will be proposed, and the damage assessment method of CFDSBP under the combination of explosion and earthquake loading will be established. The results of this study can provide the theoretical support for multi-hazard design of for CFDSBP. There also have important theoretical significance and practical values for updating the existing design concepts and codes, and ensuring safety of bridge structures under multi-hazard loading.

桥梁结构长期暴露于自然环境中，不可避免地会遭遇到多灾害荷载如地震、台风、海啸等自然灾害以及爆炸、撞击、火灾等人为事故，未考虑生命周期内的多灾害作用将会对桥梁结构以及生命财产造成重大损害。本项目以双层钢箱-混凝土组合墩柱(CFDSBP)为研究对象，考虑地震损伤的影响，研究CFDSBP在爆炸荷载作用下的动力灾变性能。主要内容包括：首先研究墩柱爆炸荷载模型和钢管混凝土动态损伤本构模型，为CFDSBP的动力响应分析提供基础支撑；其次，研究爆炸与地震作用下CFDSBP的动力损伤机理与失效模式，建立损伤破坏准则；最后研究CFDSBP动力响应简化分析方法，建立爆炸和地震作用下CFDSBP的损伤评估方法。研究成果可为双层钢箱-混凝土组合墩柱的多灾害设计等提供必要的理论支撑，对更新现有设计理念和设计规范、保证桥梁结构的安全运营具有重要的理论意义和工程实用价值。

桥梁结构长期暴露于自然环境中，不可避免地会遭遇到多种灾害如地震、台风、海啸等自然灾害以及爆炸、撞击、火灾等极端偶然事故。本项目以双层钢箱-混凝土组合墩柱为研究对象，研究其在爆炸和地震荷载作用下的动力损伤机理及其灾变失效模式。开展了空气爆炸试验，建立了可应用于模拟爆炸冲击波形成、传播及与柱相互作用过程的数值模型，并通过与试验结果对比验证了数值模型的准确性和可靠性。开展了混凝土和钢管混凝土的霍普金森压杆（SHPB）冲击试验，研究了适用于模拟冲击荷载下混凝土力学行为的材料模型，建立了钢管混凝土动态应力-应变关系的理论计算模型。开展了爆炸作用下双层钢箱-混凝土组合墩柱动力响应的试验和数值模拟研究，揭示了组合墩柱在爆炸作用下的损伤机理和破坏模式。开展了爆炸损伤组合墩柱的轴压承载力试验，揭示了爆炸损伤组合墩柱良好的剩余轴向承载性能，建立了评估爆炸损伤组合墩柱剩余轴向承载力的实用公式。开展了爆炸损伤组合墩柱的拟静力试验，揭示了爆炸损伤组合墩柱良好的剩余侧向承载力、延性性能和耗能能力。在本项目的资助下，发表学术论文18篇，其中SCI收录13篇，EI收录5篇；取得授权国家发明专利8项；培养博士研究生4人、硕士研究生4人。研究成果可为双层钢箱-混凝土组合墩柱的多灾害设计等提供必要的理论支撑，对更新现有设计理念和设计规范、保证桥梁结构的安全运营具有重要的理论意义和工程实用价值。