Abstract：In order to study the mechanical properties of frozen gravel-mixed clays，a series of uniaxial compression tests on frozen gravel-mixed clays were conducted with different temperatures and gravel contents. The test results show that the stress-strain response，uniaxial compressive strength，failure strain and elastic modulus are strongly affected by the temperature and gravel content of the specimens. Under uniaxial loading，the specimens present a typical pattern of brittle failure，and the smaller the gravel content is，the more significant the brittle failure characteristics are. The uniaxial compressive strength of the frozen gravel-mixed clay increases with decreasing both the temperature and the gravel content，and the variation degree is closely related to the structure distribution of clay-gravel. The failure strain decreases with increasing the gravel content while the effect of the temperature on the failure strain shows different characteristics under different gravel contents. The elastic modulus shows a quasi-linear increase with decreasing the temperature，and increases first and then decreases with increasing the gravel content. It is worth noting that the critical value of the gravel content depends on the temperature.
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2019, Vol. 38 
