Investigation on pile foundation bearing capacity using 1:20 laboratory model

This study aims to analyze the axial compressive bearing capacity of pile foundations through a 1:20 scale laboratory model test and to compare the results with the analytical methods proposed by Terzaghi and Meyerhof. The pile model was made of mortar concrete with a diameter of 40 mm and a length of 400 mm, reinforced with plain steel bars of Ø16 mm, and embedded in layered sand with varying densities. The testing was carried out using the displacement control method, recording the load for every 0.1 mm of settlement, and the ultimate bearing capacity (Qu) was determined at a settlement of 1.3 mm (equivalent to 1 inch in the field). The single pile SP1 test results showed an average bearing capacity of 73.073 kg in the model, which, after being correlated with the Wood’s scale effect, was equivalent to 584.587 tons in the field. A comparison with the analytical methods showed that Terzaghi’s method yielded 423.901 tons (27.49% deviation), while Meyerhof’s method produced 214.490 tons (63.31% deviation). These findings indicate that the Terzaghi method is closer to the experimental results for these conditions, whereas the Meyerhof method tends to be more conservative. This study emphasizes the importance of validating theoretical calculations with experimental test data, particularly in studies involving scale effects and layered soil conditions.