A novel method of using prefabricated weld mesh as longitudinal core reinforcement for resisting the shear in reinforced concrete beams

Abstract

Reinforced Concrete (RC) Structures occupies significant place in the development of infrastructure due to its inherent advantages. Further the development of different design theories has advanced the use of Reinforced concrete. The primary objective of the design of RC structures is the safety avoiding the occurrence of sudden failures. The RC beams must have adequate safety margin against different types of failures. The reinforced concrete beams are designed primarily for flexural and shear. In the design of a reinforced concrete member, flexure is usually considered first, leading to the size of the section and the arrangement of reinforcement to provide the necessary resistance for moments. Beams are then designed for shear. The shear failure mechanism varies depending upon the cross-sectional dimensions, the geometry, the types of loading, and the properties of the member1,2. Since shear failure is frequently sudden with little or no advanced warning, the design for shear must ensure that the shear strength for every member in the structure exceeds the flexural strength. The main mode of shear failure in reinforced concrete beams is characterized by the formation of diagonal cracks near the support regions. Normally, the inclined shear cracks forms near support and extend toward the compression zone. It is understood that any form of effectively anchored reinforcement that intersects these diagonal cracks will be able to resist the shear forces to a certain extent3-5. In general, the Steel reinforcement is used in the tension zone of concrete elements since the concrete is weak in tension. Different types and strengths of steel reinforcements are used with cement concrete of different grades. In addition to its use to resist tension in structural members, reinforcement is used in concrete construction for other reasons, such as: i) to resist a portion of the compression force in a member, ii) to resist diagonal tension due to shear in beams, walls, and columns6,7. Further the prefabricated reinforcement such as welded wire mesh also has been used as main reinforcement in RC slabs and as shear reinforcement in thin webbed concrete beams8,9