摩擦耗能式自定心预应力混凝土墙的抗震性能评估及生命周期成本分析

According to the typical damage patterns of conventional reinforced concrete shear walls, this study proposes a novel self-centering prestressed concrete (SCPC) wall with friction devices, which adopts different deformation and energy dissipation mechanisms, so that the main structure can be damage free and restore its original position after a design basis earthquake. First, the basic mechanical behaviors of the SCPC wall will be studied theoretically and experimentally, and based on these studies the optimal configuration of the SCPC wall will be investigated if necessary. Based on the numerical simulation method embedded with multiple time-variant material or analytical models, the time-dependent behaviors of the SCPC wall under the interactive action of concrete creep, shrinkage and stress relaxation of steel will be studied, so as to evaluate the seismic capacity within the entire service life. Thereafter, the deterministic analyses will be extended to probabilistic ones, and through incremental dynamic analyses the seismic fragility of the SCPC wall and its time-dependent characteristics will be evaluated. To this end, the model of life-cycle costs including initial construction costs and earthquake damage costs will be established, and through case studies, the SCPC walls will be evaluated regarding the economic indices and the rational range for the SCPC walls will be given. This study aims to solve several fundamental problems in the research and application of self-centering structures, and may provide new ideas and references to the development of seismic structures with better performance and remove (or mitigate) the necessity of post-earthquake repair.

针对传统钢筋混凝土抗震墙的典型震害，本课题从改变墙体变形形态和耗能机制的角度出发，提出一种新型的摩擦耗能式自定心预应力混凝土抗震墙，以实现主体结构在设防地震作用下的基本无损以及震后的自动复位。首先，围绕抗震墙的基本力学行为进行理论分析和实验室测试，对其构造形式做必要的优化。通过嵌入多种时变分析模型的数值模拟方法，研究抗震墙在混凝土徐变、收缩和应力松弛等因素耦合作用下的时变特性，以客观评价结构在整个服役期内的抗震能力。此后，将确定性分析拓展至概率性分析，进行增量动力分析，对结构的地震易损性及其时变特性做出评估。最后，建立包括新建成本和地震风险成本等在内的生命周期成本模型，并通过案例分析，对自定心抗震墙的经济性做出客观评价，确定其经济适用范围。本课题致力于解决自定心结构研究与应用中的若干基础性问题，为寻求具有良好抗震性能和便于（或免除）震后修复的新型结构提供参考和借鉴。

针对传统钢筋混凝土抗震墙的典型震害，本课题从改变墙体变形形态和耗能机制的角度出发，提出了一种新型的摩擦耗能式自定心预应力混凝土抗震墙，并开展了以下工作：（1）力学行为的理论分析和数值模拟研究;（2）基于性能的设计方法研究;（3）低周反复加载试验研究;（4）地震易损性分析;（5）摩擦耗能自定心预应力混凝土结构的长期性能研究;（6）基于地震易损性的生命周期成本研究以及（7）自定心抗震墙结构的工程应用。迄今已在Journal of Structural Engineering、Engineering Structures等知名国际期刊发表SCI论文11篇，参加国际、国内学术会议3次，获批两项国家发明专利，培养博士生2人，硕士研究生4人。成果获得2015年教育部科技进步一等奖（项目负责人为第一完成人），项目负责人入选国家万人计划科技创新领军人才、青年长江学者等人才计划。本课题解决了自定心结构研究与应用中的若干基础性问题，为寻求具有良好抗震性能和便于（或免除）震后修复的新型结构提供了参考和借鉴。