中文摘要：

为研究冻融循环对结构性黄土构度指标的影响，以山西阳曲一号隧道黄土为研究对象，基于综合结构势和构度概念为理论基础，对不同含水率黄土进行了不同冻融循环次数的无侧限抗压试验。试验表明：原状土样和重塑土样在含水率变大的过程中，单轴抗压强度均减小，且呈现出相同的变化趋势，而原状土样的无侧限单轴抗压强度均高于同含水率重塑土的无侧限单轴抗压强度，有着明显的结构强度。黄土的无侧限抗压强度和构度随着含水率和冻融循环次数的增加而减小的主要原因是由于黄土的结构性被土中水和冻融循环综合作用破坏的结果，该研究可为季节性黄土地区隧道建设提供科学依据。

英文摘要：

In order to research the influence of the cycle of freezing and thawing on loess＇ structural property indicators, the NO. 1 tunnel in Yangqu, Shanxi, has been taken as an object of study. Based on the theory of comprehensive structural potential and property, unconfined compression tests with different moisture content and the numbers of freezing and thawing have been conducted. The result of the tests indicates that in the growing of moisture content for both undisturbed samples and remolded samples, the uniaxial compressive strength of all the samples is decreasing with a same trend. Whereas the unconfined uniaxial compressive strength of undisturbed samples is better than that in remolded samples under the same condition of moisture content, the former has a prominent structural strength. With the growing of moisture content and the numbers of freezing and thawing, the main reason that the deterioration of un- confined compressive strength and property of loess should be the result of the loess＇ structural damage brought by water in soil and freezing and thawing. This study can be a scientific basis for the construction of tunnels in seasonal loess regions.