الفهرس 
Chapter 1 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Hollow-core slab is one of the most widely precast flooring system used in industrial, parking and residential buildings due to its fast construction, easy erection, high quality control and its light self-weight relative to the long spans it serves.
The common fabrication of Hollow-Core Slabs (HCS) in precast factories relying on a conventional roughening methodology during casting of concrete using steel fork, the induced roughened surface is not sufficient to create a proper composite action between the precast HCS and the in-situ concrete overlay.
This thesis presents experimental studies on shear-flexure capacity of composite HCS and concrete overlay. Ten full-scale HCS (265 mm height, 1200 mm width, 3000 mm long) were tested under shear loading, where one specimen as control slab and nine specimens have been strengthened with concrete overlay of 70 cm thickness using different interface bonding techniques. All slabs have been tested on the shear-span-to-effective depth ratio (a/d=2.6).
The experimental results are also compared with predicted values using the available equation in ACI 318-19, providing the required modification to create equations more simulating to the experimental results, the control specimen was following the PCI design handbook reinforcement arrangement.
The results of the experiments show the interface bond strength of each interface bond technique and conclude which technique is capable to make the concrete overlay works with its full shear capacity with the HCS in an excellent composite action. Useful information for the designers, researchers are provided in the field of rehabilitation of hollow core slabs.
The parameters were investigated: HCS web-shear strength, HCS flexure shear strength, overlay strengthening efficiency, interface sliding and peeling, horizontal shear strength of shear dowels and shear keys.
The results were presented on charts so as tables and discussed. During the thesis study, conclusions were drawn, and recommendations for future research and Engineering practice were suggested to improve the dapped end reinforcement scheme practices were recommended.