网壳结构钢与混凝土组合节点力学性能试验

Mechanical properties on steel and concrete composite joints in reticulated domes

为研究钢与混凝土组合的网壳节点在轴压和压弯荷载作用下的力学性能,对10个不同参数的钢与混凝土组合的节点进行试验研究.试验构件主要变化参数包括:内圆钢管的壁厚和半径、外圆钢管的壁厚及矩形钢管与外圆钢管的不同连接方式.试验研究表明:在轴压和压弯荷载作用下节点表现出了与钢管混凝土相似的特点,具有较高的承载力和良好的塑性变形能力;内圆钢管的壁厚和半径对节点承载力影响较大,外圆钢管的壁厚对节点承载力影响较小;连接方式对节点承载力影响较大,圆钢管高于矩形钢管的节点承载力比圆钢管与矩形钢管齐平的承载力至少提高15%;轴压荷载作用下节点的破坏方式可以分为中心压缩和梭形偏转破坏;压弯荷载作用下节点的破坏方式分为节点和钢管屈服破坏.

To study the mechanical properties of steel and concrete composite joints under axial compression loads, ten steel and concrete composite joints with different parameters were tested. The main parameter changes of test member include：an inner pipe wall thickness and the radius of the circle, the wall thickness of the outer pipe and the connections between rectangular steel tube and the outer tubes. The experimental results show that steel and concrete composite joints have much in common with steel and concrete, i.e., it has high capacity and good plastic deformation capacity under axial compression loads; the wall thickness and radius of inner pipe is larger than the wall thickness of the outer pipe on the bearing capacity. Connections have greater influence on the joints bearing capacity than others. The bearing capacity of round steel tube is higher than rectangular one and it will be raised at least 15% than the same capacity of round steel tubes and rectangular ones. Under axial compression loads, the failure mode of joints can be divided into central compression failure and spindle deflection failure. Under eccentric loading, the failure mode of joints is divided into joints failure and steel yield damage of pipe.