effect of waste glass as partial replacement of coarse aggregate for the production of solid blocks

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Effect of waste glass as partial replacement of coarse aggregate for the production of solid blocks

 

INTRODUCTION

Concrete is a composite material composed of coarse aggregate bonded together with a fluid cement which hardens over time. Most concretes used are lime-based concretes such as Portland cement concrete or concretes made with other hydraulic cements. However, road surfaces are also a type of concrete, asphalt concrete, where the cement material is bitumen, and polymer concretes are sometimes used where the cementing material is a polymer.

 

In Portland cement concrete (and other hydraulic cement concretes), when the aggregate is mixed together with the dry cement and water, they form a fluid mass that is easily molded into shape. The cement reacts chemically with the water and other ingredients to form a hard matrix which binds all the materials together into a durable stone-like material that has many uses. Often, additives are included in the mixture to improve the physical properties of the wet mix or the finished material. Most concrete is poured with reinforcing materials (such as rebar) embedded to provide tensile strength, yielding reinforced concrete.

 

After the Roman Empire collapsed, use of concrete became rare until the technology was redeveloped in the mid-18th century. Today, concrete is the most widely used man-made material (measured by tonnage).

Concrete is world’s most widely used construction material. The utilization of concrete is increasing at a higher rate due to development in infrastructure and construction activities all around the world.

GLASS: The amount of waste glass has gradually increased over the recent years due  to  urbanization  and industrialization where most of the waste glass end up in landfill  while only small  fraction  can be recycled  because  of the high cost of cleaning and colour sorting . Since glass is not biodegradable, landfill is not an environmentally friendly solution. Recent studies have shown that the waste glass can be effectively used in concrete either as aggregate (fine or coarse aggregate) or as cement replacement. Being amorphous and containing relatively large quantities of silicon and calcium , glass is in theory pozzolanic or even cementitious in nature when the particle size is less than 75 micron. Finely ground glass as oppose to coarse waste glass does not contribute to alkali-silica reaction.

The idea is that the glass can be used as an aggregate in the concrete mix by replacing some of the natural aggregates such as gravel and sand. Then, there is possibility of benefits such as follows: a minor amount of the glass is thrown away which saves the good decent landfill space, also with the use of less natural aggregates as the main components with the concrete mixes also help in the saving of time and overall cost. Therefore the experimental program of the current research was done and carried out to monitor the effect of using crushed waste glass as an aggregate component in the fresh concrete mixes on the compressive properties of the hardened concrete. All materials used in this study are locally available.

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