Abstract

In this paper, the governing equation of chloride diffusion in reinforced concrete square piles is presented. The deterioration process of a pile caused by chloride-induced reinforcement corrosion is analyzed. The time-varying degradation coefficient of the flexural rigidity of piles induced by reinforcement corrosion is obtained. The time-varying failure probability and reliability index under the displacement failure criterion are calculated by using the Monte Carlo simulation method. The sensitivity of the coefficient of variation (COV) and mean value of the significant parameters for the time-varying probability density function (PDF) curves is analyzed. The results indicate that the degradation coefficient of the flexural rigidity and the reliability index decrease with increasing service time, while the failure probability increases with increasing service time. The peak value of the PDF curve of the pile head displacement decreases as the COV of the lateral load, soil elastic modulus and mean value of the lateral load and bending moment increase. The displacement of the pile head corresponding to the peak value increases substantially with increasing lateral load and bending moment, and decreases significantly with increasing soil elastic modulus and concrete elastic modulus.

摘要

本文提出了钢筋混凝土方桩中氯离子扩散的控制方程。分析了由氯化物引起的钢筋腐蚀引起的桩的劣化过程。得到了钢筋锈蚀引起的桩抗​​弯刚度随时间变化的退化系数。采用蒙特卡罗模拟方法计算位移失效准则下的时变失效概率和可靠性指标。分析了时变概率密度函数 (PDF) 曲线的变异系数 (COV) 和重要参数平均值的敏感性。结果表明，随着使用时间的增加，抗弯刚度退化系数和可靠性指标降低，而故障概率随着服务时间的增加而增加。桩头位移PDF曲线峰值随侧向荷载COV、土弹性模量、侧向荷载和弯矩平均值的增加而减小。峰值对应的桩头位移随着侧向荷载和弯矩的增加而显着增加，随着土弹性模量和混凝土弹性模量的增加而显着减小。