الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Cracks play an important role in concrete; there are many causes of cracking in concrete. This research work presents the principal causes of cracking and detailed discussion of crack-control procedure to help the engineer in developing controlling cracks. This research work presents the result of experimental investigation. This investigation aims to enhance mechanical properties minimize shrinkage for concrete and stress intensity factors for cracked specimens. Concrete mixtures designed using coarse aggregate to fine aggregate ratio of 1.5 for four types of coarse aggregate. Pink lime stone, Dolomite, gravel, and bad grading pink lime stone. Super plasticizer type (F) according to ASTMC494 were used by weight of cement to kept the slump values at 20-22 cm for the three levels of W/C (0.4, 0.45,and 0.50) to produce concrete with high work ability . Silica fume was used as an addition to concrete mixes at 10% by the weight of cement content at three levels of cement content 350kg/m3 , 450kg/m3, and 550kg/m3 at different variables.
Polypropylene fiber was used as an addition to concrete mixes at 0.10% and 0.3% by volume fraction of concrete. Its specific gravity was 0.91 Ordinary Portland cement type( I) was used, its grades CEM I 32.5N, CEM I 42.5N, and CEM I 42.5R at three levels content 350 kg/m3 , 450kg/m3 ,and 550kg/m3 Study the effects of silica fume, polypropylene fiber, W/C, coarse aggregate types, cement contents, cement type and its grades for all concrete mixes to control cracks in concrete. Comprhessive strength, tensile strength, at different ages, and stress intensity factor (Kic) ,CMOD ,were carried out at different variables. Study the shrinkage in concrete at fresh stage and hardened stage respectively plastic shrinkage, autogenous shrinkage, free drying shrinkage, and restrained drying shrinkage and creep tensile tests were carried at different variables. from the test results of this work, the tests results were tabulated and plotted through figures detailed discussions for results were considered to obtain the best mixture of concrete for controlling cracks in concrete for shrinkage cracks.