STUDY ON STRUCTURAL DAMAGE OF MORTAR EXPOSED TO HIGH TEMPERATURE
Performance of mortar gets deteriorated after high temperature. Actually deterioration ofperformance is due to structural damage in mortar. In order to study the structure damage ofmortar exposed to high temperature, mortar with four water cement ratio respectively isinvestigated by macro-performance testing and micro-analysis. Carbonization resistance andwater absorption of mortar exposed to high temperature are discussed. The verity ofmierostructure is also investigated through differential scanning calorimetry,thermogravimetric analysis and scanning electronic microscope. The results show that a seriesof physical chemistry reactions, such as dehydration, decomposition and crystallographictransformation, occur in mortar suffered with high temperature. The reactions make structuremuch loose and porosity much larger. Finally water absorption increase sharply andcarbonization resistance gets worse. The carbonation depth and water absorption of mortarrise with an increase in temperature. And the growth rate of them increases when the exposedtemperature is over 400℃. After being suffered with the same temperature, mortar with lowerwater cement ratio has much lower carbonation depth and water absorption. Mortar thatpossesses water cement ratio of 0.4 has the largest relative carbonation depth and the largestrelative water sorption in four series of mortars.
Min Li Zhishen Wu Chunxiang Qian
College of Materials Science and Engineering,Southeast University,Jiangsu Key Laboratory for constru Department of Urban &Civil Engineering,Ibaraki University,Hitachi 316-8511 ,Japan;International inst College of Materials Science and Engineering,Southeast University,Jiangsu Key Laboratory for constru
国际会议
南京
英文
959-966
2008-10-13（万方平台首次上网日期，不代表论文的发表时间）