What is its crush strength?
When specifying pipe, the crush strength is a term used for pipes that experience a brittle failure. In other words, the crush strength is the load at which the pipe physically breaks. This is not applicable to a visco-elastic material such as HDPE or an elastic material such as CMP since the material will deflect under load to the point of failure. A HDPE pipe profile can actually deflect until the material is flattened due to reverse curvature. Therefore, an analogous test to crush strength for HDPE pipes would be AASHTO’s pipe flattening test, which requires the pipe be deflected 20% with no signs of wall buckling, cracking, splitting, or delamination at a specified pipe stiffness.
