Shear Behavior of Lightweight Fiber Reinforced Concrete Beams

In this study, fourteen reinforced concrete beams were tested to investigate the shear behavior of lightweight fiber reinforced concrete beams. Lightweight Expanded Clay Aggregate (LECA) was used as a partial and full replacement to the normal weight aggregate. The experimental program included three lightweight concrete beams with partial replacement of aggregate, nine lightweight concrete beams with full replacement of aggregate, and two normal weight control beams. In each group one beam was cast using steel fiber concrete, one with polypropylene fiber concrete, and one without fibers. The effects of parameters such as weight of concrete, type of fibers, area of stirrups, and shear span to depth ratio (a/d) on the beams behavior are presented. The response of the tested beams is analyzed in terms of mode of failure, deflection, strain, cracking load, and ultimate capacity. The test results are compared to those estimated from different design codes for lightweight concrete structures.