Viscoelastic behavior and durability of steel wire - reinforced polyethylene pipes under a high internal pressure \ud

The strength tests of steel-wire-reinforced polyethylene pipe specimens showed that, under a constant internal pressure exceeding 80% of their short-term ultimate pressure, the fracture of the specimens occurred in less than 24 hours. At pressures slightly lower than this level, some specimens did not fail in a year and a half. The analytical model developed for describing the mechanical behavior of such pipes considers that polyethylene is viscoelastic and steel is elastoplastic. This allows one to evaluate their short-term strength as well as their durability under a high internal pressure. The experimental results obtained in strength tests are explained by the redistribution of stresses between the two materials of the reinforced pipe. Calculations were carried out using the MathCAD softwar