Abstract

Various types of recyclable materials are currently used in civil engineering applications. These include tire shreds, ground tire rubber, fly and bottom ash, blast-furnace slag, steel slag, cement kiln dust, silica fume, crushed glass, reclaimed asphalt pavement (RAP),timber waste, thermocol waste and rice husk ash. Reutilization of these recyclable materials is especially beneficial in civil engineering applications that require large volumes of materials. When these waste products are used in place of other conventional materials, natural resources and energy are preserved and expensive and/or potentially harmful waste disposal is avoided. This special issue deals with the use of recyclable materials in diverse civil engineering applications focusing on sustainable development. The papers in this special issue present results of laboratory tests and important research findings for these materials, recommendations for debris recycling practices, and documented field applications of several waste or recyclable materials.In the present scenario, several buildings are being constructed ranging from ordinary residential buildings to sky-scrap structures. Invariably in all the structures, concrete plays a vital role in construction. Generally concrete is a mixture of cement, fine aggregate (River sand), coarse aggregate, water and type of admixtures used depends upon the situations. Now-a-days good sand is extracted and transported from river bed being in a long distance. The extraction of sand has become a serious issue, posing environmental degradation, thereby causing serious threats of flood or diversion of water flow. Nevertheless the resources are also exhausting very rapidly. As a result, Government imposed a state-wide ban on sand extraction from river-beds resulted rampant demand for river sand and all the civil engineering construction had become stand still. So it is a need of the time to find some partial substitute to natural river sand. By and large plain concrete is a brittle material. It is strong in compression and weak in tension due to some micro cracks formed at the mortar-aggregate interface during drying shrinkage at hardening stage. Thermocol has high thermal insulation makes it a n excellent material to use in the construction of walls and ceilings and it has high sound absorption makes it the ideal choice for sound proofing. Keeping all this in mind, an attempt was made to conduct experimental works in concrete by using thermocol. This experimental work was divided into two phases. In the first phase, workability test was conducted for reference concrete and other mixes. In the second phase strength test was conducted for reference and other mixes after 21 days curing. Cost analysis was also made for various mixes to assess economic mix. From the experimental test results, it was found that concrete mix with 0.3% of thermocol yielded better workability and higher compressive strength. Apparently such study and experimental test results will be useful to the Civil Engineering profession and society.