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Description
This thesis examines the possibility of mitigating structural damage due to expansive soil swell via redirecting the vertical swell horizontally using low stiffness intruders that are laterally-compressible. The logic follows that upon increase in moisture content of an expansive soil mass improved with compressible intruders, the swelling soil squeezes the compressible soil (radially or laterally), effectively reducing the vertical swell. As the soil mass dries (i.e., decreases in moisture content), the soil mass shrinks, and the intruder restitutes to its original shape so that the formation of soil cracks is hindered. Numerical simulations and laboratory experiments were performed to evaluate the interaction of expansive materials and buried compressible structures (i.e., intruders), with the goal of evaluating the intruder’s performance with respect to reducing swell-induced axial stresses and axial deformations. Results indicate that (1) axial swell strain is effectively reduced by lateral squeezing of a compressible intruder (i.e., a portion of the axial swell is redirected laterally) and, (2) swell-induced axial stress adjacent to the intruder is significantly reduced in inverse proportion to the intruder’s stiffness. Key findings of this study indicate that (1) the swell redirection effect increases with increasing axial stress, (2) larger intruders result in more significant swell redirection, and (3) the effectiveness of the intruder in reducing axial stress diminishes as the distance from the intruder increases. This study serves as a fundamental baseline for further studies on mitigating expansive soil swell related damage by redirecting swell strains with compressible intruders.