双层钢箱截面组合索塔力学性能试验

Experimental Investigation on Double-skin Steel-concrete Composite Pylon

设计制作了5个具有开孔板连接件和5个具有焊钉连接件的双层钢箱截面钢-混凝土组合索塔模型试件,根据索塔实际受力特性进行轴压和恒定轴力下的往复弯曲荷载试验.试验展示了使用两类连接件的双层钢箱组合索塔在不同荷载作用下的破坏形态和极限能力,结果表明:开孔板和焊钉均能约束受压钢板的屈曲波长,连接件的类型对试件破坏的具体形态有一定影响;轴压比是影响试件力学性能的主要因素,所有试件都根据其大小分为受压破坏和受拉破坏两类;无轴力和过高的轴力都会明显降低构件在往复荷载下的力学性能.最后,将试验结果与按照基于刚塑性原理的规范计算得到的承载能力进行比较.

Five specimens with perforated ribs and five specimens with studs were constructed to observe the experimental behaviour of double-skin steel-concrete composite pylon under axial load and combined constant axial load with cyclic lateral load respectively. Results of the test demonstrate the ultimate capacity and failure mode of two types of specimens with different connectors. Both perforated ribs and studs can limit the buckling wavelength of plate and to a certain extent influence the detail of failure modes. As a major influence factor, axial load level divides failure modes into two types, compression failure and tension failure. Furthermore, specimens under cyclic load show poor performance when there is high axial load or no axial load at all. At last, comparison on the bearing capacity is made between the results from experiments and calculations according to the codes, which is based on rigid-plastic principle.