大吨位预应力锚具组装件锚固性能足尺试验

广州西塔节点层系采用大直径体外预应力拉索直接对钢管柱施加楼层平面内方向的体外预应力.选取3根φ7×199的预应力锚具组装件进行了50次周期荷载试验及静载锚同性能足尺试验.采用两台YC-1350型液压千斤顶同步顶推箱梁对预应力试验索进行张拉,测定拉索的周期载荷性能、静载锚同性能、拉伸弹性模量以及极限拉力时的总应变和锚杯与锚板间相对位移,考核锚具拉伸时锚固情况、拉伸过程及卸载后锚具的变形情况.结果表明,经过50次循环加载后试验索均无断丝,破断荷载超过12151kN,其他各项指标也均符合要求,因而能保证广州西塔体外预应力设计的安全性.

Full-scale experiment on anchoring capability of large tonnage prestressing tendon-anchorage assembly

The large-diameter external prestressing cable was tensioned around the steel pipe column along the internal plane derection of the node layer in the Guangzhou Westtower, and the full-scale experiment researches on 50 times cyclic load and static anchoring capability of three φ7×199 large tonnage prestressing thendon-anchorage assembly were carried out. Two YC - 1350 hydraulic jack were adopted to jack box girder synchronously to tension the prestressing cable, and the parameters were obtained such as cyclic load capability, static anchoring capability, tensile elastic modulus, total strain and relative displacement between anchor plate and anchor ring under ultimate tension. The anchorage situation when the anchor was tensiled and the deformation conditions during the tension and after the unloading were checked. It is shown that prestressing cable did not break under 50 times cyclic load, the breaking load exceeds 12151kN, and the other indexes all meet the requirement, thus the external prestressing cable design safty of the Guangzhou Westtower can be ensured.