Nail Forces and Locus of Maximum Tension of Nailed Cut Subjected to Seismic Excitations: A Calculus Approach with Log-Spiral Failure Surface

Abstract

A vertical cut reinforced with inclined nails subjected to seismic loading was analyzed using the modified pseudodynamic approach, assuming a log-spiral failure surface. A novel calculus-based methodology has been devised to obtain the maximum individual nail force demands and locus of maximum tension, which directly affect nail length in the passive and active zone. The influence of depth of cut to wavelength ratio, nail declination, surcharge, wave amplitudes, soil’s shear strength parameters, and damping ratio were reported. The maximum nail forces required to restrict the failure of a cut have been observed to increase nonlinearly with the depth of nails. The lower angle of shearing resistance, stronger horizontal base acceleration, and closeness of frequency level to fundamental shear wave frequency claimed additional nail lengths in both active and passive zones highlighting their significance in the stability of nailed cut. Practicing engineers can use proposed expressions by employing inexpensive spreadsheet software rather than costly finite element or slices-based commercial software.