الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In recent years, the demand for structural lightweight concrete increased in many applications of modern constructions. This type owns many advantages such as lower density results in a significant benefit in terms of load-bearing elements of smaller cross-sections and reduction in the size of the foundations. The aggregates considered the former of concrete, which is, actuates about 75% of concrete volume. Using lightweight aggregate (LWA) in the concrete industry contributes to producing lightweight aggregate concrete (LWAC). Lightweight aggregate (LWA) is broadly classified into two types; natural (such as Pumice, Diatomite, volcanic, cinders, etc.) and artificial (perlite, expanded shale, clay, slate, sintered PFA, etc.
Lightweight concrete (LWC) has been successfully used since ancient Roman times. It has gained popularity due to its lower density and superior thermal insulation properties. LWC can significantly reduce a dead load of structural concrete elements compared to normal weight concrete. Concrete casts using recycled aggregates are considered green concretes as their positive impact on the environment. This research was conducted to study the efficiency of obtaining structural LWC cast using recycled aggregates as coarse aggregates. In this research, the main variables are; type of coarse aggregates used ( light brick, dolomite), used (30% ADDIPOR-55” as a replacement of coarse aggregate volume). The investigated physical properties included the unit weight and slump values as well as the main mechanical properties of hardened concrete in terms of compressive, tensile, flexural., and bond strengths.
The durability of this type was studied. The experimental program is divided into three parts. The first part studied the mechanical properties of LW-SC and how to enhance these properties using PEG. The second part studied the effect of chemical curing agents on the fresh and hardened concrete properties of LW-SC concrete. The third part aimed to study the durability of this type of concrete under the chloride and sulfate attack.
The fresh properties of LW-SC concrete were illustrated in the term of slump test. The hardened properties of LW-SC concrete were introduced in terms of compressive strength, splitting tensile, flexure, and bond tests.
Based on this study, we can obtain recycled-aggregate self-curing concrete using a suitable dosage of curing agent. Also, LW-SC concrete performed well under the attack of chloride and sulfate (in the range of this study).