螺栓预紧力对PC外挂墙板摩擦耗能装置力学性能试验研究

Experimental Research on Mechanical Properties of Friction-Based Energy Dissipation Device for PC External Wallboards by Bolt Preload

设计了一种摩擦耗能装置,它由中心钢板、一对夹紧角钢和单圆孔摩擦板组成。该装置应用于预制混凝土墙板和钢框架之间的4点连接吊装结构上部的连接处,用于摩擦耗能装置的摩擦板材料为A6061-T6铝合金板材。选取4组试件进行低周往复加载试验,各试件的螺栓预紧力分别为17.5,32.9,52.8,71.8 kN,研究了螺栓预紧力对摩擦耗能装置的滞回性能、初始刚度、临界滑动摩擦力、稳定性、耗能能力等的影响。研究结果表明:螺栓预紧力对摩擦耗能装置的力学性能具有决定性作用;试验加载结束后,L-B1试件摩擦板螺栓孔由于挤压变形,向一侧产生20mm的压缩变形;与L-B1试件相比,L-B2~L-B4试件的初始刚度值变化范围在10%左右,因此,在多遇地震作用下摩擦耗能装置具有较为稳定的力学性能;随着螺栓预紧力的增大,与L-B1试件相比,L-B2~L-B4试件的平均峰值滑动摩擦力分别提高31%、39%、55%,临界滑动摩擦力分别提高32%、40%、52%,层间位移角分别提高99%、106%、110%,耗能能力分别降低25%、29%、39%。

A friction-based energy dissipation device consisting of a central steel plate,a pair of clamping angles and a single circular hole friction plate was designed.The device was applied to the upper joint of a 4-point connection lifting structure between a precast concrete wall panel and a steel frame,A6061-T6 aluminium alloy plates were used as friction plate material.Four sets of specimens were selected for quasi-static loading test,and the bolt preloads of specimens were 17.5,32.9,52.8,71.8 kN,respectively,the effects of bolt preload on the hysteresis performance,initial stiffness,critical sliding friction,stability and energy dissipation capacity of the friction energy dissipation device were investigated;the results showed that the bolt preload force had a decisive role in the mechanical properties of the friction energy dissipation device;after the test loading,the bolt hole of the friction plate of specimen L-B1 had a compression deformation of 20 mm to one side due to extrusion deformation;compared with specimen L-B1,the initial stiffness values of specimens L-B2~L-B4 varied within 10%,therefore,the friction energy dissipation device had stable mechanical propertied.Compared with specimen L-B1,with the increase of bolt preload,the average peak sliding friction of specimens L-B2 to L-B4 increased by 31%,39%and 55%,the critical sliding friction increased by 32%,40%and 52%,the inter-storey drift angle increased by 99%,106%and 110%,and the energy dissipation capacity decreased by 25%,29%and 39%.