Chapter 5: Flexible Pavement Design
Anchor: #CACHDHGESection 1: Overview
TxDOT’s flexible pavement design procedure uses a systems approach. The design system is centered upon deflection measurements from the Falling Weight Deflectometer (FWD). These measurements are then used by a computer program to determine the material properties of the pavement layers (MODULUS) which are then used to compute alternative structural designs (FPS-19W). Designs derived by the FPS design process are always checked for shear strength adequacy using the Modified Texas Triaxial Class (TTC) design method. There are currently two alternative design procedures allowed by the department for flexible design:
- FPS-11, and
- AASHTO (1993).
This chapter discusses the following topics:
- types of flexible pavements
- design parameters (FPS-19W)
- pavement detours and widening
- design of perpetual pavements.