GEOTECHNICAL ASSESSMENT OF SOIL CONDITIONS FOR A PROPOSED MEGA STOREY HOTEL: (CASE STUDY OF THE SITE OPPOSITE WAZIRI UMARU FEDERAL POLYTECHNIC BIRNIN KEBBI, KEBBI STATE)

ABSTRACT The stability and performance of any high-rise structure depend greatly on the geotechnical characteristics of the underlying soil. This research assessed the soil conditions of the site opposite Waziri Umaru Federal Polytechnic, Birnin Kebbi, Kebbi State, in order to determine its suitability for the construction of a proposed mega-storey hotel. The aim was to evaluate the soil’s physical and engineering properties, classify the soil, determine its bearing capacity, and recommend an appropriate foundation system. The methodology involved site reconnaissance, sampling of disturbed and undisturbed soils, and comprehensive laboratory tests, including grain size distribution, Atterberg limits, and compaction tests. The results revealed that the soil is a well-graded sandy-clayey laterite, classified mainly as A-2-4 under the AASHTO system, which is generally rated as good for foundation support. The Atterberg limits indicated low to medium plasticity, with liquid limits ranging from 20–26% and plasticity indices between 9.7–11.4%, suggesting low swelling and shrinkage potential. Compaction test results showed maximum dry densities (MDD) between 1.678 g/cc and 2.05 g/cc at optimum moisture contents (OMC) of 8.1–11.5%, confirming the soil’s ability to achieve high density and strength under controlled compaction. The findings demonstrate that the soil possesses favorable engineering characteristics for supporting multi-storey structures, with minimal risk of excessive settlement or moisture-induced failure. It was concluded that the proposed site is suitable for the construction of the mega-storey hotel provided that proper foundation measures are adopted. A raft foundation is recommended for uniform load distribution; however, pile foundations may be considered for zones with variable subsoil conditions or heavy load concentrations. Additional investigations such as plate load tests and cone penetration tests (CPT) are advised to complement the present study. Adequate site drainage and removal of topsoil before foundation work are also recommended to ensure long-term structural stability. This study underscores the importance of thorough geotechnical assessment in high-rise construction projects, as it provides critical data for safe, economical, and sustainable foundation design.