PHYSICAL AND CHEMICAL CHARACTERISTIC AND MICROSTRUCTURE DECOMPOSITION OF SHIELD TUNNEL SEGMENT CONCRETE AT HIGH TEMPERATURE
Performance of shield tunnel segment concrete at high temperature has directrelation with personnel life security in tunnel,and stability and durability of reinforcedconcrete structure. Therefore,research on performance and deteriorated mechanism of shieldtunnel segment concrete at high temperature is of great importance. This paper analyzedphysical chemistry change and microstructure destruction of hardened cement paste (hcp) athigh temperature by XRD,DSC and SEM. The results of hop experiencing high temperatureshow that,AFt has tendency to transform into AFm,and amount of Ca(OH)2 is decreased.Besides,hydration products have been transformed from continuous and dense structure intodiscontinuous and multiple defects structure at elevated temperature. When temperature isincreased from 35℃ to 1000℃,hcp exists three endothermic peaks,values of peaks are 80℃-90℃,430℃-440℃ and 730℃-770℃,respectively.
shield tunnel segment concrete high temperature physical chemistry change microstructure
MU Song MA Bao-guo JIAN Shou-wei WANG Yao-cheng
Key laboratory for Silicate Materials Science and Engineering of Ministry of Education,Wuhan University of Technology,PR China
国际会议
The International Conference on Durability of Concrete Structures(2008年混凝土结构耐久性国际学术会议)
杭州
英文
556-562
2008-11-01（万方平台首次上网日期，不代表论文的发表时间）