A Case Study of Sports Hall Foundations in Guinea-Bissau—Architectural Design and Concrete Technology Challenges Under Limited Infrastructure Conditions

The construction of adequate infrastructure in low-resource regions is frequently constrained by limited technical facilities, inadequate supply chains, and the absence of standardized quality control. This study presents a case study of the reinforced concrete foundation system of a multifunctional sports hall constructed in Cacine, Guinea-Bissau, where concrete production was carried out under severe logistical and technological constraints. Following construction, laboratory investigations were performed to evaluate the transported cement sample, locally available aggregates, and concrete specimens collected on site. Cement characterization included particle-size distribution, thermal analysis, and compressive strength testing, while the concrete was assessed through compressive strength and water absorption measurements. The aggregate grading complied with the relevant technical requirements and fell within the recommended grading envelope; however, the cement exhibited lower mechanical performance than expected from its declared class, although the non-standard specimen geometry does not permit formal conformity assessment. The concrete reached an average 28-day compressive strength of 12.9 MPa and exhibited relatively high water absorption, reflecting the combined influence of volumetric batching, high water demand, limited mixing efficiency, and the absence of chemical admixtures. Scenario analyses based on the Bolomey relationship indicated that improved control of the effective water-to-cement ratio could substantially enhance concrete performance. Although the study is limited by retrospective testing and a small number of specimens, it provides practical insight into the adaptation of concrete technology to resource-constrained environments and identifies key technological priorities for future infrastructure projects in Guinea-Bissau and similar regions.