Abstract:
Numerical lateral load analysis based on the beam on Winkler foundation (BNWF) model (i.e., the p-y method) is a simple, and widely accepted tool to predict lateral responses of drilled shafts from field load tests. The lack of a site-specific p-y model for cemented soil layers such as caliche is one of the major limitations of simulating lateral load tests conducted in Las Vegas Valley. In this study, some of the existing p-y models widely used for rock materials, such as Florida Limestone and Vuggy Limestone have been evaluated to simulate lateral resistance of caliche. This has been done in the context of four lateral load tests in caliche-dominant sites from the recently constructed Raiders Stadium project. The uncertainty in characterizing material properties of caliche based on limited data from the boring logs has been addressed. The p-y analyses were performed using NVShaft, a MATLAB-based, comprehensive load analysis program. The applicability of the considered p-y models for caliche material was evaluated by quantifying the error margins between measured and predicted lateral responses from the simulations of the mentioned load tests. Correlations between such errors and the percentage of caliche in soil layers affecting numerical predictions were established, for both up to and beyond design load levels.