Improving Our Understanding of Liquefaction-Induced Displacements: Integration of Remote Sensing Data and Field Data from the 2010/2011 New Zealand Earthquakes

液化是一种重要的地震灾害，其引起的地表移动对建筑环境造成了严重的破坏。我们对液化后果的理解受到以前地震期间有关液化引起的运动(例如，横向扩散)的有限现场数据的阻碍。该项目将使用从卫星图像和激光雷达获得的位移来研究2010年新西兰达菲尔德和2011年克赖斯特彻奇地震期间液化引起的横向扩散。这些位移将与地下、地形和地质数据相结合，以提高我们对影响液化引起的侧向扩展位移的因素的理解。这项工作的结果可能会对岩土工程产生深远的影响，因为通过遥感技术测量的变形的高空间分辨率为横向扩展现象提供了新的见解。这项工作将为岩土工程界提供一种新的位移监测技术，以便今后的地震研究和危险测绘可以利用这些技术。由于结合了改进的传感器(例如50厘米分辨率的光学卫星图像、1米分辨率的激光雷达)和先进的处理算法(例如图像和数据集之间的精确地理参考)，现在可以通过遥感并在地面以精细的空间分辨率监测亚米级的位移。遥感产生的变形具有前所未有的空间分辨率，再加上克赖斯特彻奇大量地下数据的可获得性，这为我们提供了一个独特的机会，可以更好地了解影响液化引起的侧向变形的特征。该项目还将由工程地质学家进行详细的地质测绘和解释，这些信息将被用来进一步了解影响观测到的位移模式和横向扩展运动学的地质约束。这些数据将使我们能够调查地下特征、空间变异性、地质条件、地形、地面运动等对观测运动的影响和相互联系；这种理解将改进预测横向扩展位移的经验和数值模型。

Liquefaction is a significant seismic hazard in which the induced ground movements cause severe damage to the built environment. Our understanding of the consequences of liquefaction is hampered by the limited field data that exist regarding liquefaction-induced movements (e.g., lateral spreading) during previous earthquakes. This project will investigate liquefaction-induced lateral spreading during the 2010 Darfield and 2011 Christchurch earthquakes in New Zealand using displacements derived from satellite imagery and LIDAR. These displacements will be integrated with subsurface, topographic, and geologic data to improve our understanding of the factors that influence liquefaction-induced lateral spreading displacements. The results of this work potentially will have far-reaching impact on geotechnical engineering because of new insights into the phenomenon of lateral spreading provided by the dense spatial resolution of the deformations measured by the remote sensing techniques. This work will substantiate a new displacement monitoring technique for the geotechnical community such that future earthquake studies and hazard mapping can take advantage of these techniques. With a combination of improved sensors (e.g., 50-cm resolution optical satellite imagery, 1-m resolution LIDAR) and advanced processing algorithms (e.g., precise georeferencing between images and datasets), it is now possible to monitor sub-meter displacements via remote sensing and at fine spatial resolution on the ground. The unprecedented spatial resolution of the deformations produced by remote sensing combined with the availability of an enormous amount of subsurface data in Christchurch provide a unique opportunity to improve our understanding of the characteristics that influence liquefaction-induced lateral deformations. The project also will involve detailed geologic mapping and interpretation by engineering geologists, and this information will be used to gain further insights into the geologic constraints that influence the observed displacement patterns and lateral spread kinematics. These data will allow us to investigate the influence and interconnections of the subsurface characteristics, spatial variability, geologic conditions, topography, ground motions, etc. on the observed movements; this understanding will improve both empirical and numerical models for predicting lateral spread displacements.