面向超高层最大和残余变形协同控制的自复位耗能伸臂桁架设计方法

Improving the seismic resilience of super-tall building has been well acknowledged as a future development trend in civil engineering. The capacity-based design, including the energy dissipation capacity design to control the maximum deformation during earthquake and the self-centering capacity design to control the residual deformation after earthquake, is the key method to realize resilience of mega column-core tube-outrigger super-tall buildings. The outrigger with self-centering and energy dissipation capacities is an important component to achieve the abovementioned collaborative control requirements. However, a novel outrigger with self-centering and energy dissipation capacities as well as the corresponding capacity-based design method at the structural level, which aim to realize the collaborative control, have rarely reported. This project thus aims to conduct the following tasks to achieve the collaborative control: (1) Propose a novel self-centering energy dissipating outrigger and its key components; (2) Develop an energy-based design method to design the energy dissipation capacity and a residual displacement ratio-based design method to design the self-centering capacity for such novel outriggers; (3) Develop a demand determination method to calculate the energy dissipation and self-centering demands under a given collaborative control target, propose an engineering design method for the outriggers to control the maximum deformation during earthquake and residual deformation after earthquake. The research outcome will provide an important scientific support for the realization of a resilient super-tall buildings, which has considerable scientific significance and practical value.

提升超高层结构的地震功能可恢复能力是土木工程未来的发展趋势。面向震时最大变形和震后残余变形协同控制需求的耗能能力和自复位能力设计，是提升巨柱—核心筒—伸臂超高层结构地震功能可恢复能力的关键手段，兼具耗能和自复位能力的伸臂桁架是满足协同控制需求的重要构件。研究表明，目前还不存在面向结构协同控制需求的自复位耗能型伸臂桁架及其能力设计方法。因此本项目面向协同控制需求，重点研究：（1）兼具强耗能和自复位能力的新型伸臂桁架体系及其关键构件；（2）新型伸臂桁架基于能量的耗能能力设计方法，基于残余位移比的自复位能力设计方法；（3）给定超高层结构协同控制目标下的伸臂桁架耗能和自复位需求确定方法，在此基础上提出面向结构震时最大变形和震后残余变形协同控制需求的伸臂桁架设计方法。本项目可为实现超高层结构的地震功能可恢复提供重要科学支撑，具有重要的科学意义和工程价值。

提升超高层结构的地震功能可恢复能力是土木工程发展的未来趋势，本项目提出了一种自复位耗能型伸臂桁架，可实现巨柱-核心筒-伸臂桁架超高层结构震时最大变形和震后残余变形的协同控制，提升超高层结构的地震功能可恢复能力。（1）通过试验研究和数值仿真，研发了压-弯-剪耦合作用下具备强延性变形能力的新型防屈曲弦杆，采用自复位耗能型支撑作为腹杆，形成了自复位耗能型伸臂桁架，研究结果表明新型伸臂桁架具有较好的耗能能力和足够的自复位能力；（2）提出了适用于伸臂桁架的多尺度数值模拟方法，通过理论分析和数值仿真，提出了自复位耗能型伸臂桁架弦杆和腹杆的能力设计方法；（3）建立了典型超高层的分析模型，揭示了地震下不同部位伸臂桁架的耗能规律、最大变形和残余变形分布特征，提出了自复位耗能型伸臂桁架的设计参数取值方法，采用新型伸臂桁架的超高层最大变形控制效果略优于传统耗能型伸臂桁架，关键楼层的残余变形效果显著提升，实现了协同控制目标。项目研究成果可为实现超高层结构的地震功能可恢复提供重要支撑。