Experimental Study of In-Plane Shear Behavior of Fiber-Reinforced Concrete Composite Slabs

摘要

This study investigates the in-plane shear behavior of composite slabs reinforced with different types of secondary reinforcements. Experimental results of 20 large-scale composite slabs constructed with two different deck profiles (reentrant and trapezoidal) are presented. The slabs were instrumented and tested in a cantilever diaphragm configuration under monotonic in-plane shear to assess and compare the effect of secondary reinforcement on their in-plane shear capacity. Five types of secondary reinforcements were considered: Conventional WWM of sizes A142 and A98, synthetic macrofibers at dosage rates of 3.0 and 5.3 kg/m(3), and hooked-end steel fibers at a dosage rate of 15.0 kg/m(3). Tests were carried out for both strong and weak orientation of decking. The load-deflection and load-strain responses were measured, and the cracking pattern and sequence were observed. The results showed that fibers notably improved the in-plane shear behavior (strength and ductility) of the composite slabs. Steel mesh of size A142, synthetic macrofibers at a dosage rate of 5.3 kg/m(3), and steel fibers at a dosage rate of 15 kg/m(3) all provided comparable in-plane shear capacity and ductility. Therefore, they can be viewed as equivalent secondary reinforcement systems in composite slabs. The results also revealed that the deterioration of the interfacial bond between concrete and steel deck was not influenced by the type of the secondary reinforcement. (C) 2015 American Society of Civil Engineers.