RUI: Development of a Textural Weathering Classification for Limestone Using Signal Processing Techniques

风化对岩石的强度和刚度有负面影响。 当隧道和建筑物和桥梁的基础设计由风化岩石支撑时，重要的是要了解强度和刚度下降的幅度。 目前，风化是通过对岩石样本的视觉描述来评估的。 以前的研究表明，这是很容易在视觉上区分未风化和高度风化的标本，但与中间风化状态的标本往往是错误的分类。 该奖项支持基础研究，以开发基于测量的石灰岩岩石样本风化分类系统。 基于测量的系统将比基于视觉的系统更准确，并导致风化岩石支撑的基础设施的更经济和可持续的设计。 这项工作也可以用于评估岩石节理粗糙度，可以导致更安全和更经济的岩石边坡。 因此，这项研究的成果将有利于美国的经济和社会。 这项研究涉及土木工程和电气工程的本科生。 多学科的方法将有助于扩大研究中代表性不足的群体的参与，并对本科阶段的工程教育产生积极影响。这项工作将开发第一个可量化的基于石灰岩岩石标本的风化分类系统。 该系统将基于样本中结晶壳的百分比和尺寸、通过表面表征确定的微观形貌以及使用信号和图像处理算法量化的粗糙度值。 将使用工业轮廓仪、三维激光扫描仪和近距离摄影测量进行表面表征。粗糙度通常使用基于二维幅度的算法来表征。 这项工作将采用基于频率的算法，并将粗糙度评估扩展到三维。 风化分类系统将基于用于岩体分类的常见地质强度指数系统。

Weathering has a negative effect on the strength and stiffness of rock. When tunnels and foundations for buildings and bridges are designed to be supported by weathered rock, it is important to understand the magnitude of the decrease in strength and stiffness. Currently weathering is assessed using visual descriptions of rock specimens. Previous studies have shown it is very easy to visually distinguish unweathered and highly weathered specimens but specimens with intermediate weathering states are often misclassified. This award supports fundamental research to develop a measurement based weathering classification system for limestone rock specimens. The measurement based system will be more accurate than the visual based system and lead to more economical and sustainable designs of infrastructure supported by weathered rock. This work can also be utilized for the assessment of rock joint roughness which can lead to safer and more economical rock slopes. Therefore, results from this research will benefit the U.S. economy and society. This research involves undergraduate students in both civil and electrical engineering. The multi-disciplinary approach will help broaden participation of underrepresented groups in research and positively impact engineering education at the undergraduate level.This work will develop the first quantifiable textural based weathering classification system for limestone rock specimens. The system will be based on the percentage and size of fossilized shells in the specimens, the micro-topography determined through surface characterization, and roughness values quantified using signal and image processing algorithms. Surface characterization will be performed using an industrial profiler, a three-dimensional laser scanner, and close range photogrammetry. Roughness is typically characterized using two-dimensional magnitude based algorithms. This work will incorporate frequency based algorithms and extend roughness assessment to three-dimensions. The weathering classification system will be based on the familiar Geological Strength Index system used for rock mass classification.