PITA Fiscal Year 2008 Projects - Innovative Infrastructure System
   Assessment Technology

Horizontal Shear Stress Limits For Composite Precast/Prestressed Beam Construction-Extension

Precast prestressed concrete is a popular means of fabricating both buildings and bridges in Pennsylvania. In addition, the Pennsylvania precast industry supplies a large amount of product both locally and to a number of states in the region. The research project will examine the viability of eliminating horizontal shear ties between precast elements and field cast concrete toppings. The outcome of the research has the potential of benefiting local industry by reducing fabrication costs for precast beams and floor panels, improving construction safety through the elimination of trip hazards, and providing initial and long-term economic benefits. The research proposed represents an ongoing research project that will provide support for experimental verification of horizontal shear capacity. Additional funding from the Precast/Prestressed Concrete Institute has been awarded to support a graduate student researcher. In addition, the donation of specimens has been provided by New Enterprise Stone and Lime Company. The project will consist of fabricating and testing 32 composite concrete beams without shear ties in order to determine the horizontal shear capacity of the concrete. The beams will consist of a prestressed web fabricated by New Enterprise Stone & Lime Co., Inc and a cast-in-place slab fabricated in-house at ATLSS. Two different slab compressive strengths are being tested along with four different surface finishes for the interface between the concretes. These different parameters will help in understanding the horizontal shear capacity a concrete member under different conditions