Concrete is the second most utilized substance around the world behind the water. The aim of this paper is to review the environmental effect of concrete industry. It has been found that the environmental impact of concrete industry is severe in various environmental categories as global warming, depletion of ozone layer, and acidification of soil and water bodies. Moreover, concrete industry affects ecosystems and alters hydrogeological and hydrological systems. Green concrete has become increasingly popular among researchers and academics in recent years, although it is still in its infancy. This article examines the environmental impact of waste materials such as fly ash, silica fume, and slag as partial or complete replacements for cement, and of waste and recycled material as aggregates. It shows that the negative environmental effect of the concrete industry can be minimized by using these waste materials in the concrete production.

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River sand, one of the ingredients for concrete when harvested uncontrollably from the river would cause destruction to the river environment. At the same time, the increasing concrete waste disposed at dumpsite after generated from construction and demolition activity causes environmental pollution. The approach of recycling concrete waste for use as a mixing component in concrete production would lessen the heavy reliance on natural sand supplies and lower the amount of concrete waste disposed. The current study investigates the effect of recycled fine aggregate obtained from concrete waste as sand replacement on concrete's workability, compressive strength, and water absorption. Five mixtures were made using varying amounts of recycled fine aggregate (0, 10, 20, 30 and 40% by weight of sand). All specimens were subjected to water curing. Three types test were conducted namely slump test, compressive strength test and water absorption test. Findings show that the integration of recycled fine aggregate up to 20% produces concrete with the targeted strength of 40MPa. Furthermore, the water absorption of the mixes is less than 3%, allowing it to be classified as good quality. Success in blending recycled fine aggregate in concrete production would contribute to saving river sand consumption and lesser concrete waste for a cleaner environment.

The continuous construction activity increases the demand for concrete production. At the same time, the construction and demolition activity also generate solid waste which is disposed of at landfills. The approach of discarding waste such as concrete waste, brick waste, and timber waste pollutes the environment. Thus, the present research investigates the effect of integrating local clay brick waste as a partial fine aggregate replacement on the properties of concrete. Several concrete mixes were prepared by integrating various percentages of crushed clay brick ranging from 0%, 5%, 10%, 15% and 20% as partial sand replacement in concrete. All specimens were subjected to continuous water curing until the testing date which is 7 days and 28 days. The finding shows that the use of up to 10% crushed clay brick successfully enhances the compressive strength of concrete. The water absorption of concrete increase as larger content of crushed clay brick waste is integrated in the mix. Basically, the use of clay brick waste in concrete would help to reduce dependency on river sand supply for concrete manufacturing and promote a cleaner environment.