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Underground construction and tunnel excavation are known to redistribute stresses and cause ground displacement. Analytical solutions for stress distribution typically break down at shallow depths or in soil masses that exhibit high spatial variability, making numerical simulations necessary. Seeking to find new geometries and excavation strategies for underground construction, we propose to look to nature for inspiration. We extract 3-D digital twins of Florida Harvester ant (Pogonomyrmex Badius) structures from a nest cast in situ and simulate the stress and displacement fields around that nest with the Finite Element Method (FEM). Stress invariants around the main shaft are compared to those around idealized geometric representations of that shaft, i.e. helixes with a fixed pitch angle and a uniform elliptical cross-section. Helical structures made of circular cross-sections and horizontally oriented elliptical cross-sections interact in a way that reduces the risk of tension failure and distributes the shear stress more evenly. One can show that in addition to the extra stability that they offer and the lower risk of tensile or shear failure that they exhibit, helical shafts have the advantage of requiring less power to excavate than straight sub-vertical shafts.