Re: I can do tube bending analysis.

HOFFMAN@wmich.edu
Fri, 21 Apr 1995 22:34:04 -0400 (EDT)

IMHO -- Since an index of refraction is specified, that sounds like the properties are for the pure resin, which must be transparent. However, the PVC compound used for making pipe is full of fillers to extend the resin and much modify the mechanical properties. Maybe a way to find out is to "run it backwards". Take a 10' length of 4" pipe, put a short piece of steel pipe crossways under each end on a concrete floor. Rig up a dial indicator on a stand so as to measure the height above the floor of the top (or better, the bottom) of the center of the PVC pipe. Then apply a "concentrated load" (a bag of sand or concrete mix, etc.) of known weight to the middle of the PVC pipe, and measure the deflection with the dial indicator. Knowing the span of the PVC pipe between the steel pipe supports, the ID and OD of the PVC pipe, the weight of the load, and the deflection, the program can be run so as to figure out Young's modulus for the PVC. Maybe an easy experiment for someone with a dial indicator on an adjustable stand. Any volunteers? Richard Hoffman