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| QUANTITATIVE STUDY ON THE CT TEST PROCESS OF SILTSTONE UNDER TRIAXIAL COMPRESSION |
| FANG Jianyin1，DANG Faning1，XIAO Yaoting1，2，DING Weihua1，FANG Jianxi3 |
| (1. Institute of Geotechnical Engineering，Xi?an University of Technology，Xi?an，Shaanxi 710048，China；2. College of Architecture Engineering，Hubei University of Arts and Science，Xiangfan，Hubei 441021，China；3. Water Resources and Hydropower Development Corporation of the Yellow River，Zhengzhou，Henan 471000，China) |
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Abstract In order to quantitatively study the crack development of siltstone under triaxial compression using CT numbers，a damage partition method was proposed based on the theory of damage and the CT data in this study. The CT scanning section of the rock was divided into the complete zone( )，the damaged zone( ) and the hole or crack zone( ). The porosity，the damage rate，the degree of integrity of the rock were defined. The damage development of the siltstone CT test process under triaxial compression was analysed. Using this method，the role of each set of CT data in CT scanning was fully played，the damage and strain localization of the rock under loading be studied quantitatively. Only when the sample reached a high degree of damage under the confining pressure，the mesoscopic fracture cracks were developed into the macroscopic cracks，and the failure occurred，which was the reason of the increasing of rock strength and plasticity. The fracturing cracks on both ends of the specimen appeared late，and the specimen failed suddenly. The fracturing cracks of the scanning section were mainly distributed on the outer circular areas，while the fracturing cracks on middle of the specimen appeared early，had a longer expansion process，and the fracture cracks were across the scanning section.
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2015, Vol. 34 
