Composite pipe material from PET and coal combustion products

A pipe specimen was manufactured from a new composite material utilizing postconsumer polyethylene terephthalate (PET) and coal combustion byproducts. The primary objectives of this research were to determine engineering properties and durability of the composite material, and then manufacture a pipe specimen. Engineering properties determined include compressive and splitting tensile strengths, elastic modulus, and ultimate three-edge bearing strength. Tests were conducted to determine the influence of filler type, PET to filler ratio, fiber content, form of PET, and maximum filler particle size. Water absorption and sulfuric acid durability tests were also conducted. Results indicate engineering properties of the composite material engineering properties were greatly affected by the processing technique. The compressive and tensile strengths were slightly greater than ordinary Portland cement concrete, while the elastic modulus was 7 to 10 times lower. Increasing the filler content increased compressive and splitting tensile strengths. Results also showed that fiberglass fibers increased strength and resist the propagation of shrinkage cracks. Twenty-three of the 26 pipe specimens exhibited greater ultimate 3-edge bearing strengths than are required by ASTM for the 200 and 250 mm diameter vitrified extra strength clay pipes and all classes of nonreinforced concrete pipes. Further research should focus on developing better processing techniques to produce composite specimens. Further investigation should also be conducted on the influence that filler chemistry has on the durability of the composite material