基于损伤模型的盐蚀、冻融混凝土力学性能分析  

Mechanical performance analysis of salt-frozen or freeze-thaw concrete based on damage theory

作　　者：马彬[1] 叶英华[1] 孙洋[1] 

机构地区：[1]北京航空航天大学土木工程系,北京100191

出　　处：《建筑结构学报》2009年第S2期298-302,共5页Journal of Building Structures

基　　金：国家自然科学基金项目(50778010);国家科技支撑计划项目(2007BAF23B02-06);北京市自然科学基金项目(8092020)

摘　　要：基于混凝土盐冻损伤本构模型,对质量分数为3%氯化钠和5%硫酸钠混合溶液侵蚀下,经历不同冻融循环次数、不同水灰比的混凝土试验数据进行力学性能和材料损伤情况定量分析,分析结果与试验数据吻合较好;并将上述混合复合作用混凝土与单纯冻融作用混凝土的试验结果进行对比和损伤发展分析,得到以下结论:冻融次数相同时盐冻混凝土的抗压强度大于纯冻融混凝土,冻融循环次数N等于100是盐冻混凝土和纯冻融混凝土力学和损伤性能的界限点。N小于100时,盐冻混凝土的初始损伤值、相对变形和应力峰值对应的相对损伤均小于纯冻融混凝土的相应值;而在N等于150和200时,结果则相反。Currently,there is no report on the deterioration of mechanical properties of concrete suffering freeze-thaw actions or combined effects of erosion and freeze-thaw(refer to as salt-frozen).Based on the salt-frozen damage constitutive model of the concrete which has been educed and verified by the author,a quantitative analysis of the mechanical behavior and material damage was conducted on the concrete with different water-cement ratio.The concrete suffered different freeze-thaw cycles and corroded in both the 3% sodium chloride solution and the 5% sodium sulfate solution.Analysis results were in good agreement with the experimental data.From the experimental data and the analysis results of the concrete under combined actions or under freeze-thaw only,some conclusions may be drawn: with the same freeze-thaw cycles,the compressive strength of the salt-frozen concrete is greater than that of the freeze-thaw concrete.The freeze-thaw cycle N=100 is a crucial point,beyond which the mechanical property and damage performance of the salt-frozen concrete and the freeze-thaw concrete will change;when N≤ 100,the initial damage,relative deformation and the relative damage corresponding to the peak stress of the salt-frozen concrete are less than those of the freeze-thaw concrete;however,when N=150 and 200,the results may reverse.

关 键 词：盐冻混凝土 盐冻损伤本构模型 冻融循环 侵蚀与冻融混合 

分 类 号：TU528[建筑科学—建筑技术科学]