비배수 조건에서 반복하중을 받는 사질토의 B값(간극수압계수)에 따른 P파, S파 속도 및 간극수압 측정 = Determinations of P, S-Wave Velocities and Pore Water Pressure Buildup with B-value for Nearly Saturated Sands

다국어 초록 (Multilingual Abstract)

Liquefaction resistance depends strongly upon the degree of saturation, which is expressed in terms of the pore pressure coefficient, B. The B-value has been widely used to quantify the state of saturation of laboratory samples. However, it is practically impossible to determine in situ state of saturation by using the B-value. So, P-wave velocity can be alternatively used as a convenient index for evaluating the in situ state of saturation. In this paper, the Stokoe type torsional shear (TS) testing system was modified to saturate the specimen, with which it is also possible to measure P (), S-wave velocity () and the excess pore water pressure buildup in order to examine the effect of B-value for nearly saturated sands. A series of the tests were carried out at 3 relative densities (40%, 50% and 75%) and various B-values using Toyoura sand. Based on the test results, the variations of and with B-value were analyzed and compared with a existing theoretically derived formula. The normalized pore water pressure, and cyclic threshold shear strain, with B-value were also analyzed. Additionally the test results related to pore water pressure were analyzed by to apply to the field seismic analysis.

참고문헌 (Reference)

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