斜拉索钢丝断裂强度分析

Fracture Strength Analysis of Stay-cable Steel Wires

首先,以断裂力学为基础,运用有限单元软件ANSYS分析计算了用于表征斜拉索钢丝表面裂纹扩展速度的参量应力强度因子(SIF),在此基础上分析了裂纹形状参数对钢丝应力强度因子修正系数F的影响规律,并拟合出F的两参数表达式;然后,通过裂纹最深点和边缘点的对比分析得出了一种简单的预测裂纹深度的方法;最后,对比了基于断裂力学的带裂纹钢丝剩余强度分析方法的断裂韧性准则法和名义应力法的差异。研究成果对进一步完善现有斜拉索性能的评估方法有参考价值。

Based on fracture mechanics, finite element software ANSYS was adopted to calculate the stress intensity factor （SIF）which is used to characterize the surface crack propagation speed of staycables steel wire; The law that shows how the crack shape parameters influence steel stress intensity factor correction coefficient F was analyzed and twoparametric expression of the F was fitted out; Then, a simple method of forecasting the depth of crack was proposed through the comparative analysis of the deepest point and the edge point of crack; Finally, the difference was compared between nominal stress approach and fracture toughness standards which is an a nalysis method of residual strength of steel wire with crack based on the fracture mechanics; The results from this research is of value to further improving the existing performance assessment methods for stay cables with cracks.