Stability of high salinity saline soil subgrade slope under influence ofwater content and shear strength(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年3期
- Page:
- 22-32
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Stability of high salinity saline soil subgrade slope under influence ofwater content and shear strength
- Author(s):
- ZHANG Yu1; 2; LUO Yang2; XU Anhua3; FANG Jianhong1
- （1. Qinghai Transportation Research Institute, Xining 810001, Qinghai, China; 2. School of Traffic andTransportation, Lanzhou Jiaotong University, Lanzhou 730070, Gansu, China; 3. Qinghai CommunicationsTechnical College, Xining 810003, Qinghai, China）
- Keywords:
- road engineering; saline soil; slope stability; water contentstrength parameter equivalent layering
- PACS:
- -
- DOI:
- -
- Abstract:
- Amid at the solubility and hydrophilicity of different salinity types in saline soils were quite different, the influence of the relationships between the water content and shear strength of saline soils on the stability of saline soil roadbed slopes were analyzed, combined with the rainfall survey and the depth distribution of the onsite moisture, the indoor test adapted to the environmental conditions was carried out. Direct shear tests were performed on the highchlorine saline soil (CL1) and highsulfur lowchlorine saline soil (CL2) under different water content conditions, and the relationships between water content and shear strength parameters were obtained. Based on Geostudio, a water contentstrength parameter equivalent layered calculation model for saline soil subgrade was established, and the change law of soil sample matrix suction with volumetric water content was measured by volume pressure plate test. By combining the finite element analysis of saturated/unsaturated seepage and the limit equilibrium analysis of the stability of the roadbed slope, the SLOPE/W module in GeoStudio was used to calculate and analyze the operating conditions of rainfall intensity and rainfall duration influence of saline soil subgrade slope stability. Considering the relationship function between the water content and the shear strength, the stabilities of the CL1 and CL2 saline soil slopes were analyzed through the establishment of an equivalent layered calculation model of the saline soil roadbed moisture contentstrength parameters. The results show that when the water content is increased by 3% on the basis of the optimal water content, the cohesion of CL1 and CL2 decreases by 94.3% and 54.0%, respectively, the internal friction angle does not change much. When the optimal water content is reduced by 3%, the cohesion of CL1 and CL2 are increased by 277.1% and 89.7%, respectively, compared with the optimal water content, which has little effect on the internal friction angle of CL2, the internal friction angle of CL1 has decreased significantly. When the rainfall intensity is the same, the safety factor of the roadbed filled with CL1 is more obvious than that of the roadbed filled with CL2. The main reason is that the high chloride is more hydrophilic than the sulfate and the shear strength parameters are more affected by changes in moisture. 3 tabs, 14 figs, 25 refs.
Last Update: 2020-06-03