Polypropylene is a thermoplastic with excellent durability, but with time-dependent strength and stiffness properties. Highlights of our evaluation and analyses of the polypropylene chambers include the following:
Adapted AASHTO design procedures for thermoplastic pipe to the evaluate of the chambers
Conducted computer simulations under earth and live loading conditions
Monitored full-scale field tests to evaluate performance under live loads and earth loads in excess of those anticipated during service
Based on our work for this project, SGH authored ASTM F2418 standardizing design criteria and laboratory test methods.