CLT墙体-楼板T型连接抗剪性能特征值分析方法对比研究

Comparison study on characteristic analysis methods of CLT wall-to-floor T connection under shear test

【目的】力学特征值分析法是评价结构力学性能的有效方法。在木结构领域,以北美ASTM E2126标准,欧洲EN 12512标准和日本Y&K法的3种评估方法接受度较高。正交胶合木(CLT)被认为是一种可建造多高层木结构建筑的重要木质复合材料,目前针对其材料本身特性的研究较为广泛,但是针对其连接系统的开发和研究尚处于初期阶段。【方法】本研究设计了一种用于CLT墙体和楼板连接的T型金属连接件,结合对该连接件构造的抗剪试件试验结果,分别采用上述3种分析方法对节点刚度、屈服点特性和延性系数等力学性能参数进行了对比分析。【结果】Y&K法所得屈服点性质与另两种方法所得点相差较大,EN法计算所得刚度值和延性值略大于另两种方法,ASTM法和EN法在屈服荷载数值的差异性受试验曲线特征影响较大。【结论】综合比较以上对比结果,对于本文设计的CLT墙体-楼板节点,以及其他力-变形曲线发展较为平缓、破坏模式为延性破坏的木结构节点,Y&K法分析结果更具有实际工程应用意义。

[Objective]Mechanical characteristic analysis method is an effective way to evaluate structure mechanical performance.In research of wood structure field,three analysis methods are widely accepted,which are method involved in ASTM E2126,EN 12512 and Y&K method.Cross-laminated timber(CLT)is considered as an important wood composite to build high-rise wood constructions in the future.Researches on CLT material properties have been launched over years,but tests on CLT connection system mechanical performance and development are still in early stage.[Method]In this research,a T-shape metal connector was used to connect CLT wall and floor panel.Based on the shear test results,mechanical characteristic values such as stiffness,yield point and ductility ratio were determined by applying those three methods.[Result]The comparison results between methods show that the yield point calculated from Y&K is differ from other two methods,the stiffness value and ductility ratio results of EN method are higher,and the difference between ASTM method and EN method is affected by the test curve.[Conclusion]For an overall consideration,Y&K method has more practical engineering reference meaning for the type of CLT wall-to-panel connection tested here and those wood structures that have similar test curve shape and ductile failure mode.