NUMERICAL MODELLING OF GLASS FIBER REINFORCED POLYMER (GFRP) CROSSARM IN TRANSMISSION TOWER SUBJECTED TO STATIC LOADING

Abstract

Nowadays, the utilization of glass fiber reinforced polymer (GFRP) composite is being largely used in different structures. The knowledge to understand the mechanical behavior of fiberglass are extremely essential in the design and analysis of composite fiberglass. Composite materials have the ability to reduce cost especially in construction and maintenance. In Malaysia, glass fiber reinforced polymer (GFRP) was utilized as composite material in crossarm of transmission tower. However, due to some failure of GFRP crossarm, an investigation was carried out to analyze the behaviour of GFRP crossarm. Experimental testing was conducted to find out the physical and mechanical properties of existing crossarm. The results indicated that Brand A crossarm has display a superior performance in terms of physical and mechanical properties if compared with the other brands of crossarm. Maximum load capacity of GFRP was investigated by using full scale testing and numerical modelling. Numerical modelling using ANSYS software was used throughout this study to analyze the behavior of GFRP crossarm subjected to static loading. The numerical analysis then was compared with experimental testing as to validate the experimental results. It was discovered that percentage difference between experimental and numerical analysis results for all brands of GFRP crossarm falls below 5%. During the experimental testing, the Brand A sample was not failed even the load has been exceed until 80 kN which proves that Brand A sample has the ability to withstand highest working load. Parametric study for determining Factor of Safety (FOS) of GFRP crossarm for normal and broken wire condition were investigated. Strength over stress calculation was used to calculate the FOS. The result indicated that the Brand A crossarm was able to support up to 5 times Working Load (WL) for normal condition with minimum FOS of 1.08 for normal condition. Meanwhile, Brand A crossarm also able to support up to 3 times Working Load (WL) with minimum FOS of 1.10 in broken wire condition. Brand A have the highest factor of safety among all brand of crossarm. Based on depth understanding of the behaviour of GFRP crossarm, Brand A crossarm showed a high potential to utilize as composite material in crossarm of transmission tower that have a high mechanical and physical properties, high maximum load capacity and high factor of safety.