BSMPによる海底土質パラメーターの計測

抄録

For ocean development and off-shore construction, it is necessary to conduct a geological and geophysical survey of the seabed to select the most suitable and safe sustaining layer for the construction. Although there are several seabed survey methods available, improvements are still needed in order to reduce the amount of required manpower, and to improve the efficiency and accuracy of surveys.
As a means of solving the above-mentioned problems, Ono Sokki Co., Ltd. has developed a system called BSMP (Bottom Shear Modulus Profiler) based on the theory introduced by Pro. Tokuo Yamamoto and Dr. Tsuyoshi Torii of Miami University in 1986. Using this system, the shear modulus of a seabed can be obtained by observing hydraulic pressure differences on the seabed caused by waves and distortion of the sea bed caused by hydraulic pressure.
The author executed a performance test of this system off-shore of Urayasu in Tokyo Bay, with the cooperation of Ono Sokki Co., Ltd. As a result of this test, it was clarified that the shear modulus determined by BSMP at each depth of the seabed corresponded to the N-values of the boring samples.