Flexural and Tensile Performance of Laminated GFRP as Suitable Alternative to Hydraulic Steel Gates

Abstract

Hydraulic steel gates are commonly used for their superior characteristics in carrying both tensile and compressive stresses. Corrosion, operation, and maintenance costs make it essential to search for suitable alternatives. In this research, Glass Fiber Reinforced Polymers (GFRP) were investigated as a promising choice that can be used to resist flexure stresses as in case of hydraulic gates. Firstly, typical mechanical tests were conducted on nine specimens made of pure steel beams, four ribbed steel beams, twenty-four specimens of pure GFRP beams, along with four combined specimens from both materials. GFRP beams were also used in cooperation with polyester cemented sand to form a sandwich like beam. It was concluded that beams from GFRP achieved similar flexural capacity of steel beams of slimmer thickness. Combinations of steel and GFRP show satisfactory results while maintaining member ductility. The load capacity of the strengthened steel beams increased by 80% to 97% compared to specimens made from steel only. Failure modes for all specimens were introduced and compared. Moreover, numerical investigation was conducted using ABAQUS nonlinear module. Finite element models for three small gates of dimensions (1.0 x 1.0 m). A steel gate of thickness 14mm, Pure GFRP gates of thicknesses 29mm and 45mm were simulated. The 29mm GFRP gate was able to bear almost the same loads of the steel gate with equivalent deflection. Finally, it can be concluded that for small-scale hydraulic gates, GFRP can effectively be used as a suitable alternative for steel gates after setting limitations for failure strains.

Keywords

• steel
• gfrp
• flexure strength
• tensile strength
• f.e. modelling