Proc. of International Conference on Environmental Aspects of Bangladesh (ICEAB10), Japan, Sept. 2010 - 215 - WM04 Minimizing the stone dust through a sustainable way: a case study of stone crushing industry of Sylhet A. A. Masrur Ahmed 1 , H. M. A. Mahzuz 2 , M. A. Yusuf 3 1 Department of Civil Engineering, Leading University, Sylhet, Bangladesh 2 Department of Civil and Environmental Engineering, Shahjalal University of science and Technology 3 Civil Engineering Department, University of Information Technology and Sciences, Chittagong Abstract— this study concentrates on the fine aggregate that is an important factor for strength development in concreting. Generally sand is used as a fine aggregate in Bangladesh. Stone dust produced from stone crushing is the main concern to establish it as an appropriate alternative of sand and to minimize pressure on the sand as natural resources. Huge amounts of stone dust that originated from stone crusher as rubbish is going unused except for the purpose of land filling. From the study it is clear that the stone dust can be used for concreting and by substituting it to normal sand will serve huge solid waste minimization along with considerable waste recovery. It revealed that, stone dust and crushed stone concrete gained about 15% higher strength than that of normal sand. INTRODUCTION Concrete is a stone like material obtained by designing a carefully proportioned mixture of cement, sand and gravel or other aggregates and water to harden in forms of the shape and dimensions of the desired structure [7]. The economy, efficiency, durability, moldability and rigidity of reinforced concrete make it an attractive material for a wide range of structural applications [4]. Aggregate is one of the important constituents which has effect in strength development in the theory that the gaps of coarse aggregate is filled by the fine aggregate and the gapes of fine aggregate is filled by the binding materials [2]. In addition the strength of concrete mainly depends on water/concrete ratio, aggregate gradation, and aggregate size and shape, cement quality, mixing time, mixing ratios, curing etc [5]. Concrete must be both strong and workable, a careful balance of the cement to water ratio is required when making concrete [3]. Fine aggregate are basically sands won from the land or the marine environment. Fine aggregates generally consist of natural sand or crushed stone with most particles passing through a 9.5mm sieve. For concrete sand FM range is 2.3-3.1[6]. The main constituents of concrete such as sand, stone and water are mainly natural resources. They are not produced in laboratory or in any industry; they are obtained from the nature and processed to make it perfect for aggregate. For example, sand is carried by river water and then collected, and Stones are obtained by crushing of bolder using stone crusher. These resources of engineering materials (sand, stone) are limited and day by day the dependency on them must be minimized. So some other options should be introduced to replace instead of sand and stone. Stone dust is one of such alternative of Sand can fulfill the demand of fine aggregate. In Jaflong and Vulagong a huge numbers of Stone crushers are available, as a result of these extensively labor oriented economic activities, a large number of low income workers live in Jaflong [1] and Vulagong. A huge amount of Dust produced during stone crushing. They are often considered as a waste in the locality. They are not given any interest and thrown here and there. Sometime these stone powders are used for land filling and hence the lands are losing their fertility to produce crops. The main objective of the study is the evaluate relative performance of the concrete made by normal sand and stone dust where the coarse aggregate is crushed stone, in the same way the test is performed using Brick chip as a Coarse aggregate. This study ensures the stone powder or as an appropriate alternative of sand (fine aggregate) in concrete manufacturing as a building materials. As a low cost coarse aggregate Brick Chip is considered to ensure the acceptance and adequacy in construction purposes. Fig. 1: Stone dust thrown as waste METHODOLOGY In order to conduct this study steps like field observation, data collection, analysis, laboratory test, economic consideration, waste minimization practices etc measures are measured. For field observation extensive site visit is conducted including identification of the position of past, present and future condition of the area, extraction of an overall view on the life of labors, their economic status, employment opportunity, number of labors working, economic value of sand and stone dust. Data is actually collected based on survey, interviewing, case studies etc. Location is visited several times to know the existing condition. Different laboratory tests such as grain size analysis, normal Consistency, Fineness, and initial Setting time, Final Setting time etc. for different concrete and mortar materials heve been conducted, which were used in the study. These tests were performed to determine their characteristics. Standard test method ASTM C136 was used for sieve analysis of fine aggregates. The standard