ASR-硫酸盐侵蚀双重作用下混凝土的损伤特点  

The damage characteristics of concrete under two fold factors of ASR-sulfate erosion

作　　者：施韬[1] 许修超[1] 沈佳燕[1] 

机构地区：[1]浙江工业大学建筑工程学院,浙江杭州310014

出　　处：《新型建筑材料》2013年第11期18-21,共4页New Building Materials

基　　金：浙江省自然科学基金项目(LY12E08019)

摘　　要：研究了ASR-硫酸盐侵蚀双重作用下混凝土的损伤特点。碱骨料试件在不同浓度硫酸盐溶液中60℃恒温养护60周,定期测试混凝土试件膨胀值和动弹性模量。用SEM观察界面过渡区的形貌和组成。结果表明:试件膨胀值随硫酸盐溶液浓度增加依次增大,试件前期动弹性模量急剧下降,膨胀率上升缓慢;但后期,试件动弹性模量则下降极为缓慢,膨胀率曲线上升明显;高浓度硫酸盐侵蚀条件下,界面过渡区的AFt晶体明显增多,结构疏松。The tests of concrete under two fold factors of ASR-sulfate erosion are carried out in this article. Alkali aggregate specimens with different sulfate concentrations were cured in 60 ℃ for sixty weeks. Measuring the expansion rate and relative dynamic elastic modulus of concrete speciments at different age. Observing the pore structure in ITZ via SEM. The results show that the expansion of concrete increases when the concentration of sulfate adds. At the initial stage of deterioration,the elastic modulus of concrete decreases rapidly and the expansion of concrete rises slowly. But in the later stage of the deterioration,the elastic modulus of concrete decreases extremely slowly,the expansion rate of concrete curve rises significantly. For high concentration of sulfate erosion concrete specimen,the content of AFt in the ITZ grows greatly,many cracks exist in the ITZ and the structure becomes loose.

关 键 词：混凝土 硫酸盐 碱骨料反应 膨胀率 动弹性模量 界面过渡区 

分 类 号：TU528[建筑科学—建筑技术科学]