VisCPT Image Processing, Hardware Modification and Application Development

视觉圆锥贯入仪（VisCPT）是一种包含两个微型CCD摄像机的电子圆锥贯入仪。 当探测器垂直穿过土壤时，相机以两个放大级别收集土壤地层的连续图像流。 VisCPT描绘土壤类型，并通过计算机图像处理，它有助于非常高分辨率的地层特征的网站。 目前的研究工作将包括三个部分：土壤粒度的小波变换图像的功率谱的基础上的标准指数的发展;修改现有的VisCPT仪器，包括彩色相机和实时数字图像采集的适应;和现场数据收集在国家岩土工程实验（NGES）网站的金银岛在旧金山弗朗西斯科。将对收集到的VisCPT数据进行评估，特别侧重于确定土壤类型的图像纹理和小波变换技术。将连续采集高质量活塞管土壤样本，以与VisCPT结果进行比较。 VisCPT图像还将与标准压电锥（uCPT）测试结果进行比较，以说明和量化薄地层对uCPT读数的影响。 预计对VisCPT的修改将大大提高岩土工程师描述场地特征的能力，特别是在识别和定位薄层方面。 这将导致液化潜力，沉降速率和其他关键行为的预测显着改善。

The Vision Cone Penetrometer (VisCPT) is an electronic cone penetrometer containing two miniature CCD video cameras. The cameras collect a continuous stream of images of a soil stratigraphy at two levels of magnification as the probe is advanced vertically through a soil. The VisCPT delineates soil types and through computer image processing it facilitates very high-resolution stratigraphic characterization of a site. The present research effort will consist of three parts: Development of standard indices for soil grain size based on the power spectra of wavelet-transformed images; Modifications to the existing VisCPT instrumentation including adaptation of color cameras and real-time digital image acquisition; and field data collection at the National Geotechnical Experimentation (NGES) site on Treasure Island in San Francisco. The collected VisCPT data will be evaluated with specific focus on image-texture and wavelet transform techniques for determining soil type. Continuous high quality piston tube soil samples will be taken for comparison to VisCPT results. The VisCPT images will also be compared to standard piezocone (uCPT) test results to illustrate and quantify the effects of thin strata on uCPT readings. It is anticipated that the modifications to the VisCPT will substantially enhance the ability of geotechnical engineers to characterize a site, especially with regard to the identification and location of thin strata. This will lead to significant improvement in predictions of liquefaction potential, settlement rates and other critical behaviors.