| 摘要: |
| 为了准确分析氯盐侵蚀下海洋混凝土结构的耐久性，根据可靠度随机有限元法分析了材料参数、结构几何参数和环境作用参数的随机性对混凝土结构服役寿命的影响。首先基于氯盐侵蚀下混凝土结构的正常使用极限状态方程，利用摄动随机有限元法（PSFEM）建立了混凝土结构可靠度分析的梯度优化迭代分析方法，根据预设可靠度水平确定混凝土结构的服役寿命。进而利用灵敏系数分析了氯盐腐蚀下混凝土结构服役寿命对不同随机变量的敏感性。算例分析验证了本文方法具有较高的计算精度和效率。研究表明，混凝土保护层厚度对混凝土结构耐久性影响最大，需要在设计中予以特别注意，而且参数随机性对混凝土结构服役寿命具有显著影响，一旦忽略将导致设计结果偏于不安全。 |
| 关键词: 氯盐 混凝土 服役寿命 结构可靠度分析 结构耐久性 随机有限元 敏感性 |
| DOI： |
| 分类号:TU528.01 |
| 基金项目:国家自然科学基金资助项目(51168003)；广西自然科学基金项目重大项目（2012GXNSFEA053002) |
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| Stochastic finite element reliability analysis of durability of concrete structures exposed to marine environment |
|
HONG Bin
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Key Laboratory of Disaster Prevention and Structural Safety of China Ministry of Education， School of Civil Engineering and Architecture， Guangxi University
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| Abstract: |
| In order to accurately analyze the durability of concrete structure under the chlorine erosion， the parameters randomness is studied for the service life of concrete structure by use of the reliability stochastic finite element method. The parameters include concrete material parameters， geometrical parameters and environmental parameters. First of all， based on the serviceability limit state equation of the concrete structure exposed to the marine environment， the stiffness recursive equation and iteration algorithm are established by perturbation stochastic finite element method (PSFEM) and optimization algorithm. The service life of the concrete structure is predicted based on the preset reliability level. Then， sensitivity of random parameters is studied for service life using sensitive coefficients. This new method is applied to the durability analysis of a marine concrete embankment. The research results have shown that the concrete cover thickness has the greatest effect upon the concrete structure durability, to which should be paid a special attention in the design, and that the parameter randomness has a significant influence on the service life of the concrete structure. Once neglecting this parameter randomness must result in unsafe design results. |
| Key words: chloride salts concrete service life reliability analysis of structure durability of structure stochastic finite element sensibility |
