Experiment Studies And Mechanism Analysis On Different Initial Water-Saturated Red Sandstones Under Condition Of Frost And Thaw

In our country, the area of seasonal frozen soil and long-term frozen soil covers two to three of our nation area. With economy developing and western exploitation, lots of buildings for energy engineering, traffic engineering and communication engineering will be constructed on these frozen soil areas. So the research for tunnel engineering in frozen areas has been put forward a new plan, it gives a good chance for researching of frozen area engineering in our country. As the same time, lots of characters and problems of frozen areas have difference with the normal soil areas or have some same characters, but some characters make more serious in frozen areas, it gives us a lot of new challenges. Retrospective predecessor's studies and results, from frozen soil mechanics, lots of study on frozen soil have been reported in many countries. But study on rock characters under the influence of low temperature and frost and thaw is very little.Because of the varieties of nature, geology, geography, climate and water, water-saturated state for rocks is different, also it should not be ignored the rock damages by frost and thaw in the condition of different water-saturated state. Therefore, it is very interested to research the rock characters under damages by frost and thaw in the condition of different initial water-saturation. In this paper, the red sand rocks'damaged characters by frost and thaw in different initial water-saturation are studied in macroscopical and microcosmic ways, and then, studied their theory and used initial water-saturation for the damage by frost and thaw. The content is below:1 Different initial water-saturated rocks are prepared for the experiment by the theory of gas- liquid two phase balance.2 Some uniaxial tensile tests with different pressure are done on different initial water-saturated red soil rocks in the condition of five times frost and thaw. Study on the changes of rock peak strength and Young's modulus, the red soil damages by water soften and frost and thaw are studied in process of five times frost and thaw experiments.3 Some triaxial compression tests with different pressure are done on different initial water-saturated red soil rocks in the condition of five times frost and thaw. The influence of rock deformation, strength and failure by different pressure are studied, also the damage of different initial water-saturated red soil rocks in the condition of frost and thaw is studied under the different pressure, their failure theory is researched.4 Microcosmic study on the experiment process in different initial water-saturated red soil rocks in the condition of five times frost and thaw, analysis the failure theory on the relation between initial water-saturated state and damage state. From microcosmic and macroscopical studies, it is prove that results have difference in these experiment ways, maybe the background of defining for damage is different, but damage rule with initial water-saturated state is consistent.