Engineering tests of aggregate from Lightweight Expanded Slate of Manki Formation
Keywords:
Slate; bloating; lightweight; aggregateAbstract
Bloatable (expandable) argillaceous raw materials suitable for use in making lightweight aggregate exist in large quantities in Pakistan. In this paper Precambrian slate from the Attock-Cherat Ranges has been used to study its engineering properties for use as a lightweight aggregate concrete. Chemical analyses of the samples showed that loss on Ignition varies from 3.45 to 4.56 %. The high contents of iron in the form of pyrite and hematite (5.23 %) and the content of alkalies (6.6 %) are indicative of better bloating properties in slate. The samples were fired in a rotary furnace at temperature ranging from 10501150° C to achieve maximum bloating. After bloating physical tests were carried out according to the American Standards for Testing Materials (ASTM) specifications. The results of various tests like water absorption, bulk density, chloride content, and soundness properties meets the specifications of concrete and show their suitability for use as a light weight aggregate for structural purposes.
References
Asrarullah, 1972. Economic resources of North West Frontier Province. Geological Survey of Pakistan Unpublished Report, 59.
Euro Light Con, 1998. LWAC material properties, state-of-the-Art Economic Design and Construction with Light Weight Aggregate Concrete, European Union- Brite EuRam III.
Hassan, A., 1970. Crushing strength of concrete made from locally expanded clay aggregate. West Pakistan. Engineering Congress, Lahore, 15, 39-49.
Hassan, A., 1972. Pilot plant for expanded clay aggregate. Engineering News, 17, 43-51.
Hussain, A., 1981. An introductory note on prospects and potential for lightweight aggregates in Pakistan. Geological Survey of Pakistan Unpublished Report, 4.
Hussain, A., Chaudhry, M. A., Siddiqi, F. A., Zubair, M., 1983. Lightweight aggregate; A study of raw material in Pakistan, IslamabadPeshawar region. Geological Survey of Pakistan Records, 66.
Khan, M., Parker, N. A., 1970. Claystone and shale of Chittagong region (Bangladesh) for lightweight aggregate production. Geological Survey of Pakistan Records, 20, 2-17.
Kinniburgh, W., 1969. Technical Feasibility of producing lightweight aggregate from clay of West Pakistan. Building Research Station, London, 4, 1-9.
Klinifelter, T. A., 1960. Lightweight aggregates. In: Gillson, J.L. et al., Eds., Industrial Minerals and Rocks (Nonmetallic other than Fuels) (3rd ed.), AIME, New York, 487–495.
Tahirkheli, R. A. K., 1970. The geology of AttockCherat Range, West Pakistan. Geological Bulletin University of Peshawar, 5, 26. www.bst-betostyrene.com/handbook www.escsi.org/ContentPage.aspx?id=525
