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５０ｍｍ×５０ｍｍ×５０ｍｍ的一些小花岗岩块体被单轴挤压使之表面出现裂隙，然后分别预处理成干燥、水饱和与硫酸钠溶液饱和的３组样品，使之经历不同温度变幅下的冻融过程。在冻融过程中，分别记录了样品表面、表面下１０ｍｍ及２５ｍｍ处的温度变化，同时在实验前后，对所有样品都进行了超声波传输速率测定和重量测定。实验结果表明，这些小的花岗岩块体表面与内部的温度变化没有明显差异，其温度变化随外界温度而变化，但在外界温度变幅整体低于０℃时，岩石温度逐渐趋于稳定。样品在实验前后的重量变化很小，但是仍能反映最大的变化发生在水饱和的一组样品中。所有样品在实验后的超声波传输速率都明显下降，特别是在垂直于微裂隙的方向，超声波传输速率下降大于平均下降幅度，表明冻融过程中岩石内部的孔隙可能增大而微裂隙具有明显的加剧作用。
Some small granite blocks of 50mm × 50mm × 50mm were uniaxially squeezed so that cracks appeared on the surface and were then pretreated to three groups of samples that were dry, saturated with water and saturated with sodium sulfate solution, respectively, and subjected to freezing under different temperature variations Financial process. During the freeze-thaw process, the temperature changes of 10mm and 25mm below the surface of the sample were recorded respectively. Meanwhile, the ultrasonic transmission rate and the weight of all the samples were measured before and after the experiment. The experimental results show that there is no significant difference between the surface temperature and the internal temperature of these small granite blocks. The temperature changes with the outside temperature, but the temperature of the rock tends to be stable when the external temperature fluctuation is less than 0 ℃. The weight change of the sample before and after the experiment is very small, but it still can reflect the biggest change occurred in a group of water-saturated samples. The ultrasonic transmission rate of all the samples decreased obviously after the experiment. Especially in the direction perpendicular to the micro-cracks, the ultrasonic transmission rate decreased more than the average decrease, which indicated that the pores in the rock during freezing and thawing may increase and the micro-cracks have obvious Aggravate the role.