Chamila Sampath Sirimanna

Temperature Effects on Full Scale FRP Bridge Using Innovative Composite Components

Numerous large-scale demonstrator projects around the world have shown the viability of composite materials for bridge applications. Most of the projects have been directed towards the better understanding of bridge behaviour in strength and serviceability. However, the behaviour under different environmental conditions and longer term effects on durability are yet to be fully understood. This paper presents the results of an investigation on effects of temperature change into the structural behaviour of a FRP demonstrator trial bridge. It was installed at the University of Southern Queensland, Toowoomba Campus using innovative sandwich composites. It has been found that temperatures in different locations of the bridge vary for different locations within the bridge. The variation is found to reverse during day and night time. Based on the meas-ured temperature variation, some important recommendations are provided on the effects of temperature for innovative fibre composite bridge.

Compressive strength characterization of polyester based fillers

This paper investigates the compressive properties of polyester based fillers with different proportions of resin, sand and fly ash. The research program aims at developing a polymer based filler for a glass fibre reinforced polymer (GFRP) tube to be used as a structural rehabilitation system. It has been initiated to improve fundamental understanding of this material and to provide the knowledge required for its broad utilization. In this development, sample trial mixes were considered based on several weight percentages of polyester resin, fly ash and sand. These weight percentages were selected after analyzing volumetric properties of sand. The effect of resin (binder), sand and fly ash contents on the compressive strength of polyester based fillers with respect to age is reported. It has been found that at the age of 7 days all the batches reached about 90% of the compressive modulus. The experimental compressive stress-strain curves reported here were compared with established analytical models for normal strength concrete.

Fiber-reinforced polymer (FRP) repair systems for corroded steel pipelines

This chapter explores an internal FRP repair system for corroded pipelines. A review of internal corrosion defects, internal composite repair technologies, installation methods, advantages and disadvantages is presented. Subsequently, the performance of the available composite technologies for internal repair is evaluated in terms of their maximum allowable working pressure, pipe diameter and service temperature. Solutions for internal repair systems are then suggested. Finally, novel analytical methods and the results of experimental studies highlighting the potential of composite materials for internal repair of corroded steel pipelines are presented. This chapter discusses both the state of the art on the subject matter and the most recent advances in the field.

Polymer based filler materials as infill for GFRP pile connector

Recently glass fibre reinforced polymer (GFRP) tubular piles have been developed for civil engineering applications instead of conventional concrete piles. Considering their suitable applications, the new polymer based filling materials are being developed at the University of Southern Queensland as a part of work done for timber pile rehabilitation. This ongoing project aims to replace portion of the deteriorated timber pile by using GFRP piles. Due to good compressive strength, pumpability and workability, the new polymer base materials are to be filled in between GFRP pile and existing timber pile base. An ongoing research program has been initiated to improve fundamental understanding of these materials and to provide the knowledge required for their broad utilization. In this development, sample trial mixes were considered based on several weight percentages of polymer resin, fly ash and sand. Material parameters such as compressive strength, stiffness, shrinkage and gel time were achieved from the experimental investigation. It has been found that most polymer based trial mixed fillers have high compressive strength and considerable plastic region with more than 10% strain. These results imply that the polymer based filling materials are suitable for both compression and tensile loading situations. However, the behaviour of fillers with GFRP pile connector under different loading conditions is yet to be fully understood.

Analysis of retrofitted corroded steel pipes using internally bonded FRP composite repair systems

Abstract Steel pipelines play an important role in the oil and gas industry. Hence, corrosion of the steel pipe systems during its service life is a critical issue for the industry. Fibre-reinforced composites offer solutions with broad applicability and efficiency for the internal repair of these corroded pipelines. Understanding the behaviour of internal composite repair systems against different internal pressure regimes is an important aspect in the development of a repair system. This study develops the analyses of internal composite bonded repair systems for long steel pipes with an axisymmetric defect, based on Lame’s equation. Various levels of bonding between the steel and composite are studied. Fully bonded optimum internal composite repair thicknesses are determined using biaxial carbon and glass fibre composites for different levels of corrosions, using the von Mises yielding and Tsai–Hill failure criterion approaches. Two case studies are illustrated using the design nomographs. The analysis technique used was found to be accurate when compared with finite element modelling results.