摘要
提出了混凝土结构表面裂缝宽度评估的概率方法。基于开裂混凝土的控制微分方程,总结了混凝土结构表面裂缝宽度的解析计算。通过与文献中的试验结果比较,验证了该解析解的有效性。将混凝土结构表面裂缝宽度达到容许值的时间定义为失效时间,应用蒙特卡罗算法获得了与各随机变量相对应的失效时间的均值和变异系数。数值结果表明,当钢筋直径和锈蚀电流密度均服从正态分布时,失效时间分别服从正态分布和对数正态分布;保护层厚度、混凝土抗拉强度和弹性模量的变异性对失效时间几乎没有影响。最后,定量评价了钢筋直径和锈蚀电流密度对失效时间的影响。
A probability method is presented for evaluating the surface crack width in concrete structures.Based on the governing differential equation of cracked concrete, the analytical computation for the surface crack width in concrete structures is summarized.The validity of the analytical solution is verified with the experimental results obtained from the literature.If the failure time is defined as the time when the surface crack width in concrete structures reaches the allowable value, the mean value and coefficient of variance of the failure time corresponding to each random variable are obtained by the Monte Carlo algorithm.The numerical results show that,when the bar diameter and corrosion current density are both normal random variables, the failure time is a normal random variable and lognormal random variable, respectively, and that the variability of the cover depth and the tensile strength and elastic modulus of concrete has little influence on the failure time.Finally,the effects of the bar diameter and corrosion current density on the failure time are evaluated in a quantitative manner.
出处
《混凝土》
CAS
CSCD
北大核心
2008年第5期58-60,63,共4页
Concrete
基金
国家安全生产监督管理总局项目(06-170)
关键词
混凝土结构
表面裂缝宽度
评估
概率方法
concrete structure
surface crack width
evaluation
probability method
