The Plastic Pipe Profile Predicament
AASHTO’s Load & Resistance Factor Design (LRFD) for thermoplastic pipe requires many inputs from the design engineer ranging from a Deflection Lag Factor to an Installation Factor. Most of the input decisions must be made by the engineer on a project by project basis. One very important design variable, however, has to be provided by the plastic pipe manufacturer; the idealized pipe wall profile for each size of pipe. Pipe wall profiles vary from manufacturer to manufacturer, and potentially region to region from a given manufacturer. This ePipe explains why the idealized pipe wall profile for each size of pipe is critical to the project design calculations and what should be done to obtain correct values.