الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
 |  | from | 164 |  |  |
| | | from | 164 | | |
Abstract
The analysis of the field failure of plastic pipes’ shows
that the failure occurs by slow crack growth (SCG) due to the external loads. On the other hand, the standard design 7--ocedures consider the internal pressure only regardless the external loads. so, a new design procedure based on fracture
mechanics is needed.
This thesis describe a method to study the fatigue crack propagation in plastic pipes to generate kinetic parameters suitable to predict the service lifetime of the pipe under _nternal and external loads
Chapter 1 presents a review for the standard design procedure used in pipe design which are ASIM standard, ISO standard and rate process equation.
Chapter 2 is a study for the stresses and the plastic
zone at the crack tip. Also this chapter includes a study for
the requirements of linear elastic fracture mechanics (LEFM) .
In chapter 3 a fatigue machine has been designed to
produce sinusoidal load. This machine was used to study the
fatigue crack growth in PVC pipes at different load ratios
,load ratio= minimum load/maximum load). The fatigue data was
analyzed in terms of Paris equation to determine the crack.