基于可靠度分析的湿态混凝土强度模型

李鑫鑫; 郑丹

基于可靠度分析的湿态混凝土强度模型

李鑫鑫,
郑丹

重庆交通大学河海学院, 重庆 400074

基金项目: 国家自然科学基金项目(50809079)

详细信息

中图分类号: TU528.1
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出版历程
- 收稿日期: 2012-05-08
- 修回日期: 2012-05-08
- 刊出日期: 2012-05-24

WET CONCRETE STRENGTH MODEL BASED ON RELIABILITY ANALYSIS

Department of River & Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, China

More Information

Corresponding author:
LI Xin-xin: 李鑫鑫

摘要

摘要: 湿度会改变混凝土的力学参数,当外界水渗入到结构后,混凝土的力学性能会发生较大改变。该文在现有试验结果和理论模型的基础上,认为湿态和干燥混凝土强度的差异主要与表面能和弹性模量的变化有关。利用ANSYS 有限元软件模拟了不同浸没时间下混凝土试件内部的湿度分布,采用概率分布和可靠度数学模型定量计算了不同湿度下混凝土的抗压强度。该文的计算结果与试验结果吻合较好,可为真实水环境中混凝土的设计参数取值提供参考。
- 湿态混凝土 /
- 湿度梯度 /
- 表面张力 /
- 孔隙水 /
- 弹性模量
Abstract: When the ambient water penetrates into concrete, the moisture content and mechanical properties of concrete will be changed. Based on the existing experiments and theoretical models, it is assumed that the difference of dry and wet concrete strength is related to the surface energy and elastic modulus variation of material. Concrete moisture distribution is calculated by FEM software ANSYS, and compressive strength of concrete under different humidity is analyzed by a probability distribution and reliability analysis model. The results show a good agreement with that of the experiments, which can provide references for the parameter determination of concrete under real work conditions.
- wet concrete /
- humidity gradients /
- surface tension /
- pore water /
- elastic modulus

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参考文献(18)

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