Site Characterization for Soil Liquefaction Susceptibility Using Geotomography

液化引起的地面破坏是地震期间造成破坏的主要原因。将这种损害降至最低的一个重要步骤是通过对土壤进行现场测量来识别易受液化影响的场地。与超孔压发展相关的特性。现有的现场调查方法不能完全描述一个地点的特征，因为测量只能在离散的地点进行；土壤性质的空间变异性必须用其他方法来推断。该项目第一阶段的目标是开发和实施地震地理层析成像，以获得更全面的场地特征。易液化的易液化的在地震地理层析成像中，通过大量的地震波穿过土体，测量初始切线剪切模数的垂直和横向变异性。(用于液化敏感性评估的参数)。第二阶段的目标是在南卡罗来纳州查尔斯顿的一个地点应用地震地理层析成像，地震带，以便将地理层析成像与传统的场地描述技术进行比较，如标准贯入试验(SPT)和圆锥贯入试验(CPT)。已知这一地区存在易液化的土壤。

Liquefaction-induced ground failures are a major cause of damage during earthquakes. An important step in minimizing this damage is to identify sites that are susceptible to liquefaction by making in situ measurements of soil properties related to excess pore pressure development. Existing methods of site investigation are unable to characterize a site completely because measurements are made at discrete locations only; the spatial variability of soil properties has to be inferred by other methods. The objective of the first phase of this project is to develop and implement seismic geotomography to obtain a more complete characterization of sites susceptible to liquefaction. In seismic geotomography, a mass of soil is traversed by a large number of seismic waves to measure the vertical and lateral variability of the initial tangent shear modulus (a parameter used for liquefaction susceptibility evaluation). The objective of the second phase is to apply seismic geotomography at a site in the Charleston, South Carolina, seismic zone so as to compare geotomography with conventional site characterization techniques, such as the standard penetration test (SPT) and the cone penetration test (CPT). Soils susceptible to liquefaction are known to exist in this area.