Dynamic properties of unsaturated compacted soils

• Main Authors: Yu-hsuan Cheng, 鄭鈺諠
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/87227776360422581797

碩士 === 國立中央大學 === 土木工程研究所 === 98 === Dynamic properties of compacted soils are key parameters in analyzing seismic response of compacted earth dams. The compacted soil of earth dam is composed of saturated part and unsaturated part. However, there’re few literature studying the unsaturated part of compacted soils. This paper aims to analyze the dynamic properties of unsaturated compacted soils. The test materials include compacted SM, ML and CL soils. The dynamic properties of these soils are measured by resonant column test (RCT). The measured properties include the maximum shear modulus, normalized shear modulus, and damping ratio curves in the shear strain range of 〖10〗^(-4)~〖10〗^(-1) % . The results shows that shear modulus and threshold shearing strain are increased with confining pressure. As degree of saturation decreases, shear modulus are significantly increased, but threshold shearing strain is decreased. Therefore, threshold shearing strains of specimens of any saturation degree are almost the same when confining pressure is high. The test results could be combined with current results of saturated specimens. We can get the regressive formula for the maximum shear modulus and use it for future study on seismic response of compacted earth dams.