Applying Mathcad to the Highway Capacity Manual

Abstract

The objective of this study was to develop a tool for engineers and researchers to understand the underlying logic of the Highway Capacity Manual (HCM) procedures. The HCM offers a collection of methodologies and techniques for estimating the capacity and evaluation of the level of service for highway, street and transit facilities (HCM 2000). Mathcad worksheets were developed to replicate the computational procedures of five chapters of the HCM. The principal topics addressed are advantages of the Mathcad worksheets over existing implementations of the HCM, challenges associated with the implementation, and changes and additions made to the format of the HCM worksheets reflecting capabilities and limitations of Mathcad. These dynamic documents allow the user to easily explore the sensitivity of the procedures to varying equations, relationships and input parameters. Because the Mathcad worksheets display information in a manner similar to the HCM, most users will find the worksheets straightforward to use and interpret. As such the Mathcad worksheets offer better transparency than other implementations of the HCM procedures.