Prediction and Rehabilitation of Highway Embankment Slope Failures in Changing Climate

Corresponding data set for Tran-SET Project No. 17GTLSU04. Abstract of the final report is stated below for reference: "Highway slopes constructed with clayey soil are prone to desiccation cracks due to wetting and drying weather cycle, which allows greater moisture infiltration into the embankment from precipitation. Fissures formed due to extended wetting and drying cycles allow water to seep deeper into the soil than surficial wetting and increase the water content. This increases the moisture content in the soil and results in reduction in shear strength to the fully softened strength. On the other hand, development of desiccation cracks and reduction of the soil matric suction ultimately result in higher hydraulic conductivity value which causes development of higher pore water pressure. As the moisture content of the clayey soil increases, the strength reduces to a fully softened shear strength that causes frequent shallow and medium slope failures that are oriented approximately parallel to the surface of the embankment. Hence, the fully softened strength of Louisiana and Texas soils need to be quantified to develop a predictive tool for identifying high-risk zones of highway embankments. Given the documented failures in Texas and Louisiana, this research project is focused on investigating past failures to develop lessons learned and guidelines that can be implemented in the predictive framework."Tran-SET项目编号17GTLSU04对应数据集。以下为该项目最终报告的摘要以供参考：采用黏性土填筑的公路边坡易因干湿气象循环产生干裂裂隙，这会使得降水更易渗入路堤内部。反复干湿循环形成的裂隙相较于表层浸湿，可使水分更深地渗入土体并提升土体含水率，进而使抗剪强度降至全软化抗剪强度(fully softened strength)。另一方面，干裂裂隙的发育与土体基质吸力的降低最终会导致水力传导系数升高，引发更高的孔隙水压力。随着黏性土含水率升高，土体强度将降至全软化抗剪强度，进而引发频繁发生的、大致平行于路堤坡面的浅层及中层边坡失稳。因此，需量化路易斯安那州与得克萨斯州土体的全软化抗剪强度，以开发用于识别公路路堤高风险区域的预测工具。鉴于得克萨斯州与路易斯安那州已有边坡失稳的记录，本研究项目旨在对既往失稳案例开展调研，总结经验教训并制定可应用于该预测框架的相关指南。