国家游泳中心子结构模型往复水平加载试验

Cyclic lateral loading test on a sub-structure model of the National Swimming Center

为研究国家游泳中心“水立方”内墙受力最大部分的抗震性能,而完成了1/3缩比的子结构模型在重力荷载代表值和往复水平力作用下的试验。子结构模型的破坏形态为杆件局部屈曲和杆件母材拉断,破坏的杆件主要位于墙面上;杆端贴板使塑性铰和破坏位置转移至杆件上,避免了杆件与节点连接焊缝的破坏。子结构模型受推和受拉的名义屈服位移角分别为1/127及1/100左右,水平荷载分别为880kN和746kN,为顶部附加重量的1.73倍和1.47倍;加载至水平力为附加重量的2倍以上、顶点位移角为1/50左右,承载力尚未下降,水平位移仍能增大。试验结果表明,子结构模型具有大的承载能力、良好的变形能力和耗能能力。

To study the seismic behavior of the heavily loaded part of the internal wall of the National Swimming Center, the so called ＂Water Cube＂, an experiment was conducted on a one-third scaled sub-structure model subjected to representative gravity load and cyclic lateral load. Damage of the sub-structure model are in the forms of local buckling and tension fracturing of the base metal of the structural members, and most of the damaged members are at the wall surfaces. Due to the cover plates welded at member ends, the plastic hinges and the damage locations are away from the connections between the members and the joints, thus brittle failure of the weldments is avoided. The nominal yield top drift ratios of the model under push and pull forces are about 1/127 and 1/100, respectively, and the corresponding strength is in the range between 880kN and 746kN, 1.73 and 1.47 times that of the representative gravity load of the model, respectively. The lateral load is 2 times that of the representative gravity load and the top drift ratio is about 1/50, whereas the strength of the model is less than the maximum strength while the lateral displacement may increase further. The sub-structure model exhibits high load-carrying, deformation and energy dissipation capacities.