<p>This study evaluates the response of a single pile embedded in sand to blast-induced loads resulting from an internal explosion in an adjacent tunnel. A three-dimensional finite element model was developed to simulate the interaction between the tunnel, soil, and pile foundation system. The model employed the concrete damage plasticity (CDP) model for the reinforced tunnel and pile, the Drucker-Prager model for the soil, and the Johnson–Cook (J-C) model for the reinforcements embedded in the tunnel lining and the pile. The blast event was simulated using the conventional weapons (ConWep) method. The response of the pile was assessed in terms of the lateral deflections and the damage sustained. A parametric study examined the effect of soil properties, angle of internal friction, Young’s modulus, and density on the blast response of the pile. Results indicate that lateral pile deflection increases with a higher angle of internal friction of the soil but decreases with greater soil density and Young’s modulus. The study’s findings offer insights into the blast-induced susceptibility of piles located near tunnels and emphasize the critical soil characteristics that influence their interaction.</p>