Performance appraisal of RC beams using welded wire fabrics as lateral reinforcement in seismic zones

Abstract

Ductility is the key to design earthquake resistant structures. More rigid the structure or the element, more it attracts inertia forces. Structures and elements of infinite rigidity are out of question. Codes of practice also advocate design philosophies wherein effects of small earthquakes are to be absorbed with little or no damage, medium with damage to such extents that rehabilitation is possible and large earthquake effects to be catered without collapse. To absorb the tremendous energies that are input to structures and elements unless ductility is ensured, performance levels proposed by codes and standard practices cannot be attained. Lateral ties hold longitudinal reinforcement of R.C.elements in place and also confine the concrete. The basis of the present work is the usage of welded wire fabrics as lateral reinforcement in RC beams. A series of beams were tested with lateral ties and welded wire fabric at discrete locations and welded wire fabric alone throughout the beam with different mesh opening sizes. This paper presents the encouraging results with marginal increase in strength and considerable improvement in ductility in addition to reduced crack widths as observed for specimens having welded wire fabric with smaller mesh openings as lateral reinforcement by confining concrete. 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.