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| Experimental study on stress-strain behaviour and failure strain energy density of frozen clay-gravel mixtures |
| ZHANG Yonggan1，LU Yang1，2，LIU Sihong1，2，WANG Tao1，MAO Hangyu1 |
| (1. College of Water Conservancy and Hydropower Engineering，Hohai University，Nanjing，Jiangsu 210098，China；
2. International Joint Laboratory of Long-term Behaviour and Environmentally Friendly Rehabilitation Technologies on Dams，Hohai University，Nanjing，Jiangsu 210098，China) |
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Abstract Clay-gravel mixtures(CGMs) are composed of clay and gravel. With the accelerating construction of engineering projects in cold regions，it is of great importance to figure out the mechanical properties of frozen CGMs. In this study，CT scanning tests were first carried out on compacted CGMs at room temperature，the skeleton structure and pore structure distribution characteristics of samples with different gravel contents were obtained. Besides，a series of unconfined compression tests were carried out on frozen CGMs to study the effects of temperature，gravel content，water content，and loading rate on their stress-strain characteristics and failure strain energy densities. The test results show that frozen CGMs exhibit typical brittle failure characteristics，which are greatly affected by temperature，gravel content，water content and loading rate. The failure strain energy density decreases with increasing temperature and gravel content，and increases nonlinearly with the increase of the loading rate. Furthermore，the failure strain energy density of the frozen CGM first increases and then decreases with water content，indicating there is a“critical water content”at which the frozen CGM bear the strongest resistance to failure.
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2022, Vol. 41 
