为研究FRP复合材料横担在三向荷载作用下的空间受力性能,结合某输电线路FRP复合材料塔架,对FRP复合材料横担进行了三向荷载作用下的足尺试验,观察了试验过程及现象,分析了FRP复合材料横担体系的荷载-位移关系曲线,并对横担梁和拉索中钢套管和FRP复合材料的应变变化规律进行了研究。结果表明:钢套管与FRP复合材料具有良好的粘结性,FRP复合材料之间出现轻微撕裂但并未发生破坏;横担梁中部截面外鼓变形,拉索侧向变形很明显。横担梁的荷载-位移关系基本成线性变化,FRP复合材料横担体系的荷载富余度系数约为4.0,表现出较好的受力性能。横担梁及拉索的钢套管应变均小于FRP复合材料的应变,FRP复合材料同一截面应变分布较为均匀。拉索较横担梁更容易发生破坏,设计时应对拉索进行一定的加强处理。研究结论将为FRP复合材料横担的推广应用提供技术参考。
Combined with the FRP composite material transmission tower,a full scale experimental study on mechanical properties of the FRP composite cross arm system under three-way loads was performed in order to research space mechanical properties of FRP composite material cross arm system under three-way loads. The experiment process and phenomena were observed. The load-displacement curve of composite material cross arm system was analyzed. Strain change laws of steel casing and FRP composite material in the cross arm beam and inhaul cables were also investigated. The research results show that the junction surface between the steel casing and FRP composite material has good bonding and some slight avulsion between the FRP material layers is also observed though without damage. The middle cross-section deformation of the cross arm beam is large and the lateral displacement of inhaul cables is very obvious. The load-displacement curve of cross arm features linear variation rule and the load rich degree coefficient of composite material cross arm system is about 4. 0,which shows that has a good mechanical performance. The strain values of steel casing in the cross arm beam and inhaul cables are less than the strain of FRP composite material and the strain distribution in the same section of FRP composite materials is approximate homogeneous. Compared with the cross arm beam,the inhaul cable is prone to damage. Therefore,some strengthening measures need to been taken in the inhaul cables. The research results will provide the technical reference for the design and application of composite materials cross arm.