ANALYSIS OF HORIZONTAL SHEAR STRENGTH OF PRECAST PRESTRESSED CONCRETE SLAB AND CONCRETE TOPPING COMPOSITES

This study aims to compare the horizontal shear strength at the interface between precast prestressed concrete slabs and concrete toppings under three different slab surface conditions: smooth or unintentionally roughened (Type 1), intentionally roughened by 3mm latitudinal indentations (Type 2), and intentionally roughened by 6mm latitudinal indentations (Type 3). The theoretical values for shear strengths for all types of the concrete slab-topping composites were compared to the experimental values calculated from vertical deflection and strain values which were obtained using the Three-Point Bending Test. The characteristics of the failures were also examined. The study shows that the horizontal shear strength and the deflection depend on the roughness of the surface of the concrete slabs. When compared to Type 1 concrete slabs under the load of 1,300kg, the concrete slabs with roughened surfaces showed stronger horizontal shear stress (by the factor of 0.898 for Type 3 and 0.953 for Type 2) and less deflection (by the factor of 1.113 for Type 3 and 1.053 for Type 2). The results highlight the importance of the roughened surface of the concrete slabs in enhancing the horizontal shear strength in the concrete slab-topping composites which could be of great benefit to engineering applications. (C) 2019 INT TRANS J ENG MANAG SCI TECH.