Estimation model for steel wire crack propagation and its application in calculation of pre-corrosion fatigue life
Zheng Xianglong1 Xie Xu1 Li Xiaozhang2 Qian Liqin3 Shen Yonggang1
1. Zhejiang University, Hangzhou 310058, China
2. Kunming University of Science and Technology, Kunming 650504, China
3. Jinhua Wucheng Highway Administration Bureau, Jinhua 321000, China
Abstract：To provide practical parameters of crack propagation model for damage tolerance analysis of bridge cable steel wires, fatigue threshold (ΔKth) and data in crack propagation calculation were censused according to relevant experimental results of different kinds of steel. An empirical model suitable for different yield strength and stress ratios was established. Based on the proposed model, a method was proposed to predict the fatigue life of corroded steel wires according to the one-dimensional crack growth hypothesis. In addition, an example was given to analyze the fatigue life of corroded wires under constant-amplitude and variable-amplitude fatigue loads. The results show that the correlation between yield strength and fatigue threshold of pearlitic steel increase with the stress ratio. The crack propagation model and the proposed initial crack depth hypothesis can well simulate the fatigue discreteness and endurance limit property under constant-amplitude load. The results of fatigue assessment of corroded wires under variable-amplitude loads are very sensitive to the fatigue threshold. However, the residual life predicted by conservative threshold indicates that, steel wire cables with slight corrosion can serve normally during routine inspection period if the maintenance is conducted in time.
郑祥隆 谢旭 李晓章 钱利芹 申永刚. 钢丝裂纹扩展估算模型及其在预腐蚀疲劳寿命计算中的应用[J]. 土木工程学报, 2017, 50(3): 101-107.
Zheng Xianglong Xie Xu Li Xiaozhang Qian Liqin Shen Yonggang. Estimation model for steel wire crack propagation and its application in calculation of pre-corrosion fatigue life. 土木工程学报, 2017, 50(3): 101-107.
