Strenght of Appraisal Adsorption Section Unsaturated Soils

• Main Authors: Hu Zheng Xinguang, 胡鄭信光
• Other Authors: Shi-Fon Su
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/98869525577602216870

碩士 === 東南科技大學 === 防災科技研究所 === 98 === Based on a consideration of the low cost effectiveness, this research uses conventional direct shear apparatus for proceeding direct shear test of unsaturated soil and for determining the relation between the degree of saturation and the shear strength obtained from unconsolidated-undrained tests. However, this study uses constant temperature oven to control water content of soil up to anticipant conditions. The unsaturated specimens were performed in the temperature of 50℃ and the drying time of 60 minutes. Then the sample of unsaturated soil is proceeded direct shear tests. To simulate rainfall infiltrated into the unsaturated soil, upper load cell of shear box has been modified to permeable. In other words, the water can infiltrate into the unsaturated specimen during the loading. For type 1 of soil (42% clay-size particles), this results obtained by a series of the direct shear tests show that angle of undrained friction is to equal to13.0°and the undrained cohesion is to equal to31.5kPa when the degree of saturation is in the range of 85.2% to 87.8%. In addition, angle of undrained friction is to equal to 42.9°and the undrained cohesion is to equal to32.2kPa when the volumetric water content is in the range of 28.0% to 28.5%. For type 2 of soil (47% clay-size particles), this results show that angle of undrained friction is to equal to46.4°and the undrained cohesion is to equal to30.1kPa when the degree of saturation is in the range of 79.3% to 80.8%. In addition, angle of undrained friction is to equal to 27.5°and the undrained cohesion is to equal to42.0kPa when the volumetric water content is in the range of 27.9% to 28.6%.