Development of NYSLAB

Abstract

Since the development of ILLI-SLAB software in 1979, researchers have made significant contributions to the capabilities of tools for jointed-pavement analysis. These efforts have culminated in some commercial and noncommercial software packages such as JSLAB and ISLAB2000. Even though JSLAB has undergone several improvements since 1986, the underlying core of the software maintains the characteristics of the initial ILLI-SLAB code. A thorough review of JSLAB2004 revealed that it would be beneficial to redesign the software completely to take advantage of modern computer resources and finite element modeling techniques available today. For this reason, a new analysis tool was developed that significantly improves on the efficiency and capabilities of JSLAB2004. The improvements led to NYSLAB, a tool that (a) has no limitations on the number of jointed slabs and foundation layers analyzed, (b) more accurately models the contact between debonded slabs and between the bottom slab and the top foundation layer, (c) models the foundation layers beyond the edge of the slabs to predict more accurately the edge deflections and stresses, and (d) significantly improves the capabilities for modeling a nonlinear thermal profile on all slab layers to predict more accurately their curling response. A series of parametric studies was conducted to evaluate the performance of NYSLAB and highlight the new and improved capabilities.