الفهرس 
Introduction
Fracture testsOnly 14 pages are availabe for public view
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Abstract
This study reports and discusses the results of an experimental investigation on fracture properties of high strength concrete. The investigation used three levels of concrete grades (30, 50, 70 MPa ), five coarse aggregate proportions of total aggregate, two coarse aggregate sizes (10, 20 mm), two coarse aggregate types (dolomite, gravel), effect of elevated temperatures four ratios of Initial crack depth according to specimen depth (0.2, 0.3, 0.4, 0.5 ). fracture properties (KI, KII ) were determined. A comparison study was performed. It was found that: (a) The fracture properties (KI , KII) increase as the maximum size of coarse aggregate and compressive strength of concrete increase; (c) KI and KII are observed to be higher in gravel than in dolomite by 10%; (d) Generally, the values obtained for KI and KII showed a significant trend to decrease with increasing temperatures; (e) At temperatures more than 200°C, using dolomite aggregate with 10 mm maximum nominal size leads to higher values of stress intensity factors compared with 20 mm .