钢锚板式钢-混组合索塔锚固区PBL剪力键传力机理分析

Mechanical Property of PBL Shear Connector in Cable-Pylon Anchorage Zone with Steel Anchor Plate

摘要: 索塔采用混凝土、锚固区采用钢锚板的斜拉桥索塔锚固体系，构造简单，受力合理。本文针对这种新型锚固体系中PBL剪力键进行了静力性能有限元分析，分析结果表明，在沿整个PBL键穿孔钢筋长度方向上，传力主要集中在钢锚板附近的长度；对于多层PBL键穿孔钢筋，沿着竖向方向从上到下PBL键穿孔钢筋传递的力逐渐减小；当增大PBL键穿孔钢筋直径或增加钢锚板厚度时，PBL键的应力和位移都随着减小；不考虑钢锚板与混凝土之间的粘结作用时，与钢锚板接触但无粘结作用的混凝土应力水平较低且分布均匀。这种新型锚固体系采用PBL剪力键作为钢构件与混凝土之间的连接件能很好的利用材料性能，受力性能良好。

Abstract: Cable tower anchorage zones, using concrete and steel anchor plate of cable support tower ca-ble-stayed bridge system, have simple structure and reasonable stress. The static performance of the PBL shear keys in the neotype anchoring system has been carried on using finite element analysis. The analysis results show that on the perforated steel bar length direction along the whole group’s key, force mainly concentrated in the length of the steel anchor plate near. For multilayer perforated steel group’s key, from top to bottom along the vertical direction, PBL key perforated steel transmission force decreases. When increasing the PBL key perforated rebar diameter or increasing the thickness of the steel anchor plate, the stress and displacement of the PBL are decreased. Regardless of cohesive action between steel anchor plate and concrete, concrete stress level is lower and evenly distributed. This new type of anchorage system adopting PBL shear keys as joints between steel and concrete can make good use of the material performance. The mechanical performance is good.