TY - JFULL AU - Wang Yong and Kong Ling-Wei and Guo Ai-Guo PY - 2010/12/ TI - Strength Characteristics of Shallow Gassy Sand in the Hangzhou Bay T2 - International Journal of Geological and Environmental Engineering SP - 560 EP - 565 VL - 4 SN - 1307-6892 UR - https://publications.waset.org/pdf/11582 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 47, 2010 N2 - In view of geological origin, formation of the shallow gas reservoir of the Hangzhou Bay, northern Zhejiang Province, eastern China, and original occurrence characteristics of the gassy sand are analyzed. Generally, gassy sand in scale gas reservoirs is in the state of residual moisture content and the approximate scope of initial matric suction of sand ranges about from 0kPa to100kPa. Results based on GDS triaxial tests show that the classical shear strength formulas of unsaturated soil can not effectively describe basic strength characteristics of gassy sand; the relationship between apparent cohesion and matric suction of gassy sand agrees well with the power function, which can reasonably be used to describe the strength of gassy sand. In the stress path of gas release, shear strength of gassy sand will increase and experimental results show the formula proposed in this paper can effectively predict the strength increment. When saturated strength indexes of the sand are used in engineering design, moderate reduction should be considered. ER -