GEOTECHNICAL CHARACTERIZATION OF LEVEE BY INTEGRATED GEOPHYSICAL SURVEYING
A geophysical investigation was undertaken to establish an integrated geophysical survey method helpful for the assessment of failure vulnerability of earthen levees during flooding or earthquake. The tested geophysical methods involves multi-channel surface wave dispersion measurement (MASW), capacitively coupled (CC) resistivity measurement, multi-frequency electromagnetic (EM) survey, high-resolution seismic reflection survey using S-wave type Land Streamer, and conventional direct current (DC) resistivity survey. Because the former three methods require no fixing of the sensors on the ground, which ensures high field performance, they are utilized to delineate the whole profile along levee. The latter two methods are applied to the zones partly but they can provide detailed profiles of the anomaly zones within and beneath the levee body. The CC resistivity measurement as well as EM survey successfully reconstructed resistivity profiles along the levee, and delineated anomalously high or low resistivity zones in the levee body. The MASW method reconstructed the shear wave velocity structure along a levee, and successfully imaged relatively high or low velocity zones in the levee body. High-resolution seismic reflection surveying delineated the layered structure in the levee and in the underlying foundation sediments. Resistivity data obtained by the CC resistivity and EM survey were used to estimate permeability of the levee body materials based on the empirical relationship between them for unsaturated soil materials. The S-wave velocities estimated from MASW and seismic reflection surveys were used as the good indices to evaluate the stiffness of levee body. As a result, the investigation demonstrated the feasibility of applying integrated geophysical surveying to the integrity assessment of levees for the prevention of levee failure caused by flooding and earthquakes.
Levee Vulnerability assessment Permeability Stiffness Integrated geophysics
Inazaki Tomio Sakamoto Tadahiko
Public Works Research Institute Public Works Research InstituteMinami-hara 1-6, Tsukuba, JAPANMinami Public Works Research Institute Public Works Research Institute Minami-hara 1-6, Tsukuba, JAPANMinam
国际会议
西安
英文
1-11
2005-11-01（万方平台首次上网日期，不代表论文的发表时间）