Development and Performance Evaluation of a Soil Testing Device for Prototype Foundation Investigation

Abstract

Foundation investigation is a critical prerequisite for safe and economical civil engineering construction, yet conventional field testing methods such as the plate load test are often costly, laborious, and inaccessible for small to medium-scale projects. This research focused on the performance evaluation of a fabricated soil testing device designed for prototype foundation investigation. The study involved the design analysis, fabrication, and comprehensive performance evaluation of the device, followed by correlation and validation of results with conventional plate load tests. Steel materials were selected based on mechanical properties testing, with the chosen specimen exhibiting an ultimate tensile strength of 433 N/mm² and yield strength of 277 N/mm². Laboratory testing was conducted on soil samples from three pits at depths of 0.5 m and 1.0 m, encompassing physical and mechanical properties tests. The fabricated device was evaluated using square, rectangular, and circular prototype foundations, with load-settlement responses recorded and analyzed. Results demonstrated that the device provides reliable estimates of bearing capacity ranging from 570 kN/m² to 620 kN/m², with settlements at failure between 1.75 mm and 3.90 mm, all well below the 25 mm allowable limit. Correlation analysis revealed a strong positive relationship with conventional plate load test results (R² = 0.932), validating the device's reliability. The fabricated testing device offers a portable, cost-effective, and practical alternative for foundation investigation, particularly suitable for small to medium-scale civil engineering projects where conventional testing may be prohibitive.