الفهرس 
Ch. 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Curing is the process of controlling the rate and extent of moisture loss from concrete during cement hydration. It may be either after it has been placed in position or during the manufacture of concrete products, thereby providing moisture and time for the hydration of the cement to occur. Since the hydration of cement does take time (days, and even weeks rather than hours), curing must be undertaken for a reasonable period of time to achieve potential strength and durability. The object of the present research is to use available self-curing agents in Egypt to produce self-curing self-compacting concrete. These materials can absorb water from the mixture and then release the moisture into concrete. Self-curing agents added into concrete during the mixing process. Self-Compacting Concrete incorporating two different fine materials (Fly Ash and Cement Kiln Dust) as a partial replacement of Portland cement were used to produce selfcuring self-compacting concrete (SCSCC) mixes. Polyethylene glycol, wood powder and lightweight aggregates were used as self-curing agents in different mixes. The present work aims also at improving and amplifying the knowledge of the time-dependent behaviour of SCSCC as well as its pore structure properties. The effects of many factors that would affect the time-dependent behaviour of SCSCC were investigated. Timedependent behaviour of SCSCC was investigated in terms of its mechanical properties and time-dependent deformations. Mechanical properties were determined in terms of compressive strength, tensile strength and modulus of elasticity tests, which were carried out at different ages. Time-dependent deformations were expressed in terms of shrinkage. In this research, the main parameters included the materials used to produce SCC, types of self-curing agents, self-curing agents ratio, The dimensions of concrete specimens used for measuring shrinkage strains were (1 00x 100x500) mm. Compressive strength and modulus of elasticity were measured on cubes (150~150x150m m). Pore structure of SCSC mortar was investigated in terms of total pore volume, total pore area, porosity, pores shape and pore size distribution. The results show that it is possible to produce SCSCC using cheap materials from nature. The compressive strength of the self- curing self-compacting concrete ranged from 65% to 90% of the compressive strength of the corresponding SCC mixes that were subjected to water curing. The best curing agent was Poly ethylene glycol with a content of 2% by weight of cement and Fly ash and 4% by weight of cement and Cement Kiln Dust.