多塔斜拉桥强震作用下的损伤模式及其优化控制研究

Multi-tower cable-stayed bridge is one of the most important structural systems in see-crossing engineering in China. Ensuring the earthquake safety of multi-tower cable-stayed bridges is the urgent demand of our social and economic development. However, the earthquake prevention and disaster reduction technologies for multi-tower cable-stayed bridges are relatively weak, especially lack of research on the damage failure mode and its control of multi-tower cable-stayed bridges. .In this project, the damage control system for the multi-tower cable-stayed bridges subjected to strong earthquakes is investigated with respect to rapid earthquake resilience, which includes three aspects. 1) The appropriate seismic damage indices for key members of multi-tower cable-stayed bridges are proposed to describe the multiple plastic hinges subjected to strong earthquakes. And the global seismic damage index is proposed based on the demand of earthquake resilience. 2) The design parametric analysis of multi-tower cable-stayed bridges is investigated to obtain various possible damage modes with regard to the constraint system of tower and girder, type of tower, number of auxiliary piers. The rational damage mode with high energy dissipation and rapid resilience is proposed together with the realization of parameter condition. The damage control objectives of damage indices are determined in order to realize the optimal damage mode. 3) The damage control effects of multi-tower cable-stayed bridges are discussed with respect to the installation of energy dissipation devices on the auxiliary piers and dual supports between tower and girder. The contradiction of different seismic damage indices is determined, on the basis of which the seismic control system and design method to realize the optimal damage mode of multi-tower cable-stayed bridges is proposed.

多塔斜拉桥是我国跨海工程中重要的结构体系之一，保障其抗震安全性是我国社会、经济发展的迫切需求。然而，多塔斜拉桥防震减灾技术研究相对薄弱，尤其对多塔斜拉桥损伤破坏模式及其控制研究甚少。.本项目研究强震作用下具有功能可快速恢复性的多塔斜拉桥损伤控制体系，主要包括：1）提出适用于描述多塑性铰区的多塔斜拉桥关键构件地震损伤指标，并基于功能可恢复性需求建立整体地震损伤指标评价方法；2）针对塔-梁约束方式、桥塔塔型以及辅助墩数量等开展体系参数化分析，明确多塔斜拉桥体系参数变化时的各种可能损伤模式，进而提出具有高耗能且快速恢复能力的合理损伤模式及其实现体系参数条件，并且明确多塔斜拉桥为实现最优损伤模式需要设定的损伤控制目标；3）研究多塔斜拉桥塔-梁间的双排支座处和辅助墩柱间设置减震装置的损伤控制效果，明确不同地震损伤指标间的控制矛盾性，建立多塔斜拉桥最优损伤模式的减震控制体系及其优化设计方法。

多塔斜拉桥是我国跨海工程中重要结构体系之一，保障其抗震安全性是经济发展的迫切需要。然而，多塔斜拉桥防震减灾技术研究相对薄弱，尤其对多塔斜拉桥罕遇地震下损伤破坏模式及其控制研究甚少。本项目首先提出适用于描述多塑性铰区的多塔斜拉桥关键构件地震损伤指标，并针对塔-梁约束方式、桥塔塔型以及辅助墩数量等开展参数化分析，明确多塔斜拉桥体系参数变化时各种可能的损伤模式，进而提出合理损伤模式及其体系参数条件，并且明确多塔斜拉桥为实现最优损伤模式需要设定的损伤控制目标。在此基础上，研究多塔斜拉桥塔-梁间的双排支座处和辅助墩柱间设置消能减震装置的损伤控制效果，明确不同地震损伤指标间的控制矛盾性，建立多塔斜拉桥最优损伤模式的减震控制体系及其优化设计方法。