FEASIBILITY OF COMPOSITE STRUCTURES IN SL ATS OF REINFORCED-CONCRETE

Agricultural concrete structures are reinforced by means of steel rods . Because steel is corrosive, its life in reinforced structures is red uced when exposed to manure gases or liquids. Research has been conduc ted to develop a new reinforcing rod made of glass fiber and plastic a s well as of high resistance to corrosion. Although the material offer s improvements, its structural behaviour is still unknown. The model d eveloped in this study compares steel rods and the new glassfiber rein forced plastic rods as reinforcement in slats for beef floor. Since pl astic rods are non-corrosive, the thickness of concrete protection has been reduced as compared to that required by the Canadian Building Co de, cracking can be neglected in the concrete, and more important defl ection can be tolerated by the plastic. Being brittle but possessing a high tensile resistance (690 MPa), its allowable stress must be reduc ed adequately. The theoretical results show that the appropriate steel section in a slat can be replaced by an identical section of fiber-gl ass reinforced plastic rod. The deflection, however, will be twice the expected deflection with steel rods. For typical slats, the design is controlled by the deflection. As fiber-glass stirrups are not availab le, the shear stress has to be carefully considered. The cost of fiber -glass reinforced slats is higher than the conventional steel reinforc ed slats.