在讨论冻土脆性破坏特征的基础上,分析了线弹性适用条件及平面应变断裂韧度测试对试样尺寸的要求。在测试方法上,详细说明了试样的制备,条件载荷值Pq的确定以及实验过程的一些细节问题。最后就冻结黄土KⅠc(Kq)测试结果,分析了KⅠc(Kq)与温度、含水量及加载速率的关系 On the basis of discussing the characteristics of brittle failure of frozen soil, the requirements of linear elasticity test and plane strain fracture toughness test on sample size are analyzed. In the test method, the preparation of the sample, the determination of the condition load value Pq and some details of the experimental process are described in detail. Finally, the KⅠc (Kq) test results of frozen loess were analyzed, and the relationship between KⅠc (Kq) and temperature, water content and loading rate was analyzed