Abstract
Increasing amount of construction waste and, concrete remnants, in particular pose a serious problem. Concrete waste exist in large amounts, do not decay and need long time for disintegration. Therefore, in this work old demolished concrete is crashed and recycled to produce recycled concrete aggregate which can be reused in new concrete production. The effect of using recycled aggregate on concrete compressive strength has been experimentally investigated; silica fume admixture also is used to improve recycled concrete aggregate compressive strength. The main parameters in this study are recycled aggregate and silica fume admixture. The percent of recycled aggregate ranged from (0-100) %. While the silica fume ranged from (0-10) %. The experimental results show that the average concrete compressive strength decreases from 30.85 MPa to 17.58 MPa when the recycled aggregate percentage increased from 0% to 100%. While, when silica fume is used the concrete compressive strength increase again to 29.2 MPa for samples with 100% of recycled aggregate.
Highlights
Concrete is the premier construction material across the world and the most widely used in all types of civil engineering works, including infra-structure, low and high-rise buildings, defense installations, environment protection and local/domestic developments
Concrete mixes with compressive strength of 30MPa are made using recycled aggregate with percentage (0, 50, and 100) % of the total coarse aggregate with and without adding silica fume
The use recycled aggregate as an aggregate cause a reduction in the compressive strength of concrete in comparison with concrete made with natural aggregate only, these percentages of reduction are (30, and 43) % for (50, and 100)% replacement of natural aggregate
Summary
Concrete is the premier construction material across the world and the most widely used in all types of civil engineering works, including infra-structure, low and high-rise buildings, defense installations, environment protection and local/domestic developments. Concrete is a manufactured product, essentially consisting of cement, aggregates, water and admixture(s). Among these aggregates and, inert granular materials such as sand, crushed stone or gravel form the major part. Aggregates have been readily available at economic prices and of qualities to suit all purposes [1]. In recent years the wisdom of the continued wholesale extraction and use of aggregates from natural resources has been questioned at an international level. This is mainly because of the depletion of quality primary aggregates and greater awareness of environmental protection. Many countries throughout the world have introduced various measures aimed at reducing the use of primary aggregates and increasing the use of recycled aggregates as a partial or full alternative (if any possible) of natural aggregate to produce recycled aggregate concrete, where it is technically, economically, and environmentally acceptable [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
