往复荷载下预应力正交胶合木剪力墙抗侧力性能研究  

Lateral performance of post-tensioned cross-laminated timber shear walls

作　　者：孙晓峰[1] 何敏娟[1,2] 李征[1,2] Sun Xiaofeng;He Minjuan;Li Zheng(Department of Structural Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Performance Evolution and Control for Engineering Structures of the Ministry of Education,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092 [2]同济大学工程结构性能演化与控制教育部重点实验室,上海200092

出　　处：《土木工程学报》2020年第3期11-18,共8页China Civil Engineering Journal

基　　金：国家自然科学基金(51778460);国家留学基金委项目(201706260124)。

摘　　要：侧向荷载作用下,正交胶合木(cross-laminated timber,CLT)剪力墙的侧向承载力往往因墙体连接区域发生破坏而骤降。为了避免该破坏特征,提出在CLT墙板中贯穿无黏结预应力钢绞线,进而构成预压于基础上表面的预应力CLT剪力墙。通过拟静力往复加载试验,共测试了3面具有不同初始张拉力的无耗能件预应力CLT剪力墙和1面装有耗能件的预应力CLT剪力墙,所有试件均为2层楼层的缩尺墙体试件,且上、下层墙板间布置有经特殊构造设计的CLT-钢组合楼板系统。基于试验数据,分析侧向荷载作用下,墙体试件的力学性能参数,水平侧移、钢绞线张拉力变化特征和墙体破坏模式,计算墙板与钢基础间的最大静摩擦系数,研究耗能件对预应力墙体耗能能力的提高效果。结果表明:预应力CLT剪力墙具有良好的抗侧力性能,且加载结束后墙体试件几乎完好;位于上、下层墙板间的CLT-钢组合楼板系统能够在有效传递层间竖向力的同时,缓解其中的CLT楼板可能发生较大横纹受压变形的问题;耗能件能够一定程度上提高预应力CLT剪力墙的耗能能力,然而,耗能件与CLT墙板的连接方式还有进一步改进的空间。For the post-tensioned cross-laminated timber(CLT)shear walls under the lateral loads,their lateral bearing capacities may decline significantly,once the concentrated damages occur within the metal connection area.To avoid such a damage mode,it is proposed that the post-tensioning steel strands should be incorporated into the CLT shear wall panels,forming the post-tensioned(PT)CLT shear wall.The CLT shear wall panels are post-tensioned to the foundation by the PT strands.Three PT-only CTL shear walls with different initial post-tensioning stress and one energy-dissipating PT CLT shear wall were tested under the quasi-static reversed cyclic loads.Each scaled shear wall specimen is composed of the upper CLT wall panel,the lower CLT wall panel,and the middle structurally designed CLT-steel hybrid floor diaphragm system.For both the PT-only CTL shear walls and the energy-dissipating PT CLT shear wall,the mechanical properties,the deformation mode,variation characteristics of the post-tensioning force,and the damage modes were analyzed,based on the experimental results.The maximum static-friction coefficient between the CLT and the foundation was also calculated.Furthermore,the improved energy-dissipating ability provided by the adopted dissipaters was also studied.It is found that the PT CLT shear walls can provide ideal lateral load-resisting performance.Besides,almost no damages were observed on the shear wall specimens after the tests.The structurally designed CLT floor diaphragm can reduce the deformation of the CLT floor panels under the perpendicular-to-the-grain compressive stress,while transferring the force from the upper wall panel to the lower wall panel efficiently.It is confirmed that the adopted dissipaters can improve the energy-dissipating ability of the shear walls to a certain extent;whereas,the dissipater-to-CLT connectingmethod can be further improved in the future to give full play to the energy-dissipating performance of the dissipaters.

关 键 词：正交胶合木 预应力木剪力墙 往复加载试验 抗侧力性能 耗能能力 

分 类 号：TU366.2[建筑科学—结构工程]