铜川紫红色软砂岩冻结效应实验CT识别

The CT Identification of Tongchuan Purple Soft Sand Rock Under Frozen Effect

冻融问题是寒区岩土工程中的重要问题,针对西部大开发中这一较为突出的问题,从细观损伤力学的角度,运用先进的CT设备观测陕西铜川地区紫红色软砂岩在受到不同冻融循环次数、冻结温度、冻结速度时,其内部损伤变化状况。研究结果发现随着冻融循环次数的增加,岩样CT均值减小、内部损伤逐渐增大;随着冻结温度的降低,岩样CT均值增大、内部损伤降低;岩样冻结后CT均值增大,但与冻结速度没有关系。本文还从岩样内部水分迁移、颗粒重组等方面对损伤变化产生的原因进行了分析。

The problem of freezing and thaw is an important one in geotechnical engineering of cold regions. In this paper, from the meso-damage mechanics, the CT technology is used to scan the meso-damage of Tongchuan purple soft sand rock separately under the varied time of freezing-thaw circle, the varied freezing temperature and the varied freezing rate. The results of experiments show that the CT number of rock sample increases with the freezing-thaw circle, that the CT number of rock sample increases after frozen, and that the average of CT number increase with reduction of the freezing temperature, but does not with the freezing rate. In addition, from the view of water migration and granule recombination, the phenomena of the experiment are explained.