Steel Fiber Concrete Slabs on Ground a Structural Matter
Text of Steel Fiber Concrete Slabs on Ground a Structural Matter
ACI STRUCTURAL JOURNALTitle no. 103-S58
Steel Fiber Concrete Slabs on Ground: A Structural Matterby Luca G. Sorelli, Alberto Meda, and Giovanni A. PlizzariAn extensive experimental investigation with the aim of studying the structural behavior of slabs on ground made of steel fiberreinforced concrete (SFRC) is presented in this paper. Several fullscale slabs reinforced with different volume fractions of steel fibers having different geometries were tested under a point load in the slab center. A hybrid combination of short and long fibers was also considered to optimize structural behavior. Experimental results show that steel fibers significantly enhance the bearing capacity and the ductility of slabs on ground. The nonlinear behavior of these SFRC structures is well captured by performing nonlinear fracture mechanics analyses where the constitutive relations of cracked concrete under tension were experimentally determined. Finally, from an extensive parametric study, design abaci and a simplified analytical equation for predicting the minimum thickness of SFRC slabs on ground are proposed.Keywords: pavement; reinforced concrete; slabs on ground.
INTRODUCTION In the last decades, the use of steel fiber-reinforced concrete (SFRC) has significantly increased in industrial pavements, roads, parking areas, and airport runways as an effective alternative to conventional reinforcement (that is, reinforcing bars or welded mesh). Because heavy concentrated loads from industrial machinery and shelves may cause intensive cracking and excessive deformation of pavements, a diffused fiber reinforcement may help the structural behavior. Many of these pavements are slabs on ground that are statically undetermined structures. For this reason, even at relatively low volume fractions (