Investigating the influence of the radius and the thickness in impact behaviour of GFRP pipes used in oil and gas industry

Abstract

Nowadays, composite materials have replaced conventional materials due to their high strength to weight ratio. Currently, their use is expanding in offshore structures, where minimising the total weight of the structure is critical, especially for pipes with a few thousand meters length. Composite materials have been extensively studied in flat geometries, however the literature around curved structures is very limited. The purpose of this investigation is to study the response of gas and oil pipes that are made of glass fibre reinforced polymer (GFRP), under impact loading. More specifically, it has been experimentally examined how the pipe diameter and its thickness affect the impact response. It is known that layered composite structures are susceptible to delamination (ply separation), an imminent phenomenon that could be caused from impact events. These events may be frequent in a hostile environment, like deep water, where those pipes are installed. A parametric non-linear finite element investigation has been conducted in Abaqus and results will be validated by observations of damage evolution and force-displacement measurements. All models took account for the shear stresses between plies and the Hashin failure criterion will be employed in the ply-by-ply failure analysis. The value of the fracture toughness in mode I and mode II of the composite that is required in the analysis and has been experimentally measured. The work is aiming to improve pipe design and prolong its life when operating in demanding environments.

Date of Award	3 Jan 2020
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Constantinos Soutis (Supervisor)