Simulation of GRP Pipes Materials and Installations Parameters Expermentally and Using FEA

Abstract

In many applications flexible pipes have to be buried at different depths whereby they are subjected to soil and traffic loads. Design and installation codes and procedures for such pipes are limiting the pipe diameter deformation to certain specific values. In some instances manufacturers and installers don't take into consideration conditions such as variation of soil stiffness, pipe bedding angle, and traffic loads. The individual behavior of the composite pipe wall was never modeled in any of the calculations performed by the manufacturers. Further more, the effect of soil-pipeline interaction was never properly addressed in the design procedures used.

In this work, an analysis of GRP pipe installation is developed to study the interaction between a buried flexible pipe and surrounding supported soil. The results of the analysis are applied to computational model using FEA (Finite Element Analysis) to determine the pipe deformations at variable soil stiffness around the pipe. Then, testing is done to compare FEA results with laboratory testing

Finite element analysis method is implemented and used to simulate GRP pipes subjected to various conditions of soil pressure distribution and develop a What.if analysis for different soil, and pipes manufactures. The results obtained from simulation of deflection pattern for two different manufacturers are compared with ASTM 3839 D-88 for underground installation of flexible reinforced thermosetting resin pipes. The simulated model used two major manufacturers of GRP pipes, allowing variation of soil stiffness and simulating realistic boundary conditions so in order that reliable deformations can be predicted. The results available from one of the GRP_ manufacturer's didn't comply with the ASTM 3839-D 88 for 5% pipe deflection. This simulation procedure proved to be an efficient methodology for pipe analysis.

A semiemperical methodology for the relationship for pipe in soil system for predication of the pipe and pipeline performance was developed in this work. The work developed a •unified integrated approach for composite soil structure, which may be used by the designer, manufacturer and installers of GRP pipe.