Investigation of Shear Strength of Subbase-Subgrade Interface with Geosynthetics Reinforcement Utilizing A Large-Scale Direct Shear TestQais S. Banyhussan, Hanan A. hassan and Badr A. HamadE3S Web Conf., 427 (2023) 03007DOI: https://doi.org/10.1051/e3sconf/202342703007