Compressive Strength and Wetting–Drying Cycles of Al-Hofuf "Hamrah" Soil Stabilized with Cement and Lime

The practice of designing load-bearing walls with stabilized earth-based material is currently increasing in most developed countries. Potentialities of earth-based materials have room for more exploration, investigation, and promotion among building industry stakeholders globally. This research aims to analyze the compressive strength and durability of “Hamrah” Soil to assess its fitness in construction. Such a study is intended to get international and local (Saudi Arabia) construction practitioners’ confidence about soil usage in the construction industry. To achieve this goal, sufficient soil material was procured from the Al-Hofuf region in eastern Saudi Arabia. Several geotechnical experiments were carried out to characterize and identify Hamrah Soil properties. The soil samples were classified in adherence to both the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO) system. Stabilizing agents (cement and lime) were added at different percentages (0, 2.5, 5, 7.5, 10, 15% of the dry soil weight) to enhance their structural properties. Based on the acceptance criteria of 2 MPa strength, more than 5% cement maximized the stabilized rammed earth (SRE) sample strength more than 2 MPa (up to 6.3 MPa at 15% cement content), whereas 10% lime reached only1.46 MPa, which proved the efficiency of cement stabilization over lime. Micro-characterization techniques utilizing XRD, SEM, and durability tests also lent credence to the effectiveness of cement in the stabilization regime, giving more fibrous formations and a reduction in weight loss below the acceptable limits compared with the case of lime stabilization.