Birch, Howarth, Marshall
Testing and Processing # 1979 Brigthon
The paper is a brief resum of a large project which has sought to investigate the use of fracture mechanics in evaluating the failure properties of a number of common thermoplastics pressure pipe materials. In this outline, the results of tests made on uPVC and YDPE pipes are described. Pre-notched pipes have been tested under pressure to assess the variation in failure strength as a function of crack size. Also, samples cut from pressure pipes have been tested in a more conventional manner using tensile and bending tests to assess fracture toughness values. It has been found that the extrapolation of both pipe and sample data to long term loading situations gives good correlation of data.
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