Research on structural damage developments of loess under stress and moisture | 湿载条件下黄土结构性损伤演化特性研究

Chinese. 分析压缩和增湿条件下黄土结构性损伤的演化规律，为黄土地区的工程建设提供参考。对含水率为2%，5%，10%，18%，21%，25%的原状土及重塑饱和土(含水率为44%)进行侧限压缩试验，测定并分析不同含水率条件下黄土的孔隙比与压缩应力的关系。基于对试验结果的分析，当湿度较小时，原状黄土仍具有较高的结构强度，曲线比较平缓；反之，当压缩应力大于结构强度时，黄土的结构已经被破坏，压缩变形逐渐增大。基于应力分担的概念，建立了一个描述湿载条件下黄土结构性损伤演化特性的参数，并进一步分析了湿载条件下黄土结构性损伤的演化规律，表明随着湿载作用的增强，黄土结构性逐渐减弱，宏观上表现为抗力的减小。损伤演化规律能为黄土地区工程的设计和施工提供一定的参考，在工程设计和施工中，应充分考虑黄土结构的特殊性并提出相应的防护措施。

English. The research was conducted to analyze the structural damage developments of loess under stress and moisture and to make some references for constructing infrastructures in the loess region. The compression tests of intact loess and remold-saturated loess are conducted under different moistures 2%, 5%, 10%, 18%, 21% and 25% to study the relationship between compression stress and void ratio. Based on the results of compression tests of loess, when the moisture is low, there is high strength for intact loess and the curves between void ratio and logarithmic stress are steady, otherwise, when the compression stress is bigger than the structural strength, and the structural of loess is damaged, and the compression displacement is increased gradually. Based on the concept of stress distribution, a parameter of structural damage developments is proposed under stress and moisture. Further more the change law of structural damage developments is analyzed, and it shows that the structure of loess is weakened gradually with the action of stress and moisture, the resistance ability is reduced. The structural damage ratio of loess structural proposed herein can provide some reference for the design and construction in loess region so that specific of loess is considered and the corresponding measure is prepared.