Tensile Strengths of Concrete Containing Sawdust Ash from Different Calcination Methods

Ettu, L. O. and Ezenkwa, C. S. and Awodiji, C. T. G. and Njoku, F. C. and Opara, H. E. (2016) Tensile Strengths of Concrete Containing Sawdust Ash from Different Calcination Methods. IJSRSET, 2 (4). pp. 349-355. ISSN 2395-1990 | Online ISSN : 2394-4099

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Abstract

This work investigated the tensile strengths of concrete containing sawdust ash from different calcination methods. SawDust Ash (SDA) was produced using three different calcination methods namely: Open Air Calcination (OAC), Stove Calcination (SC), and Furnace Calcination (FC). OPC was partially replaced with SDA from each of the three calcination methods at 5%, 10%, and 15%. Nine concrete cylinders of 150mm x 300mm were produced for each of the three percentage replacement levels of OPC with SDA and for each of the three calcination methods, making a total of eighty one concrete cylinders with OPC-SDA binary blended cement for the three different calcination methods. Nine control concrete cylinders, with same dimensions of 150mm x 300mm, were also produced using 100% OPC. This gives a grand total of 90 concrete cylinders. A mix ratio of 1: 2: 3.5 (blended cement: sand: local stone) was used for the concrete. Batching was by weight and a constant water/cement ratio of 0.6 was used. All the concrete cylinders were cured in water by immersion. Three concrete cylinders from each of the three SDA calcination methods and for each of the three percentage replacement levels of OPC with pozzolan, as well as three control concrete cylinders were tested for saturated surface dry bulk density and crushed to obtain their split tensile strengths at 28, 90, and 150 days of curing. Excel Spreadsheet Regression Analysis was used to develop empirical models for predicting the split tensile strengths of OPC-SDA concrete for each of the three calcination methods. It was found that Split tensile strength values for FC were much greater than those for OAC and SC for all the days of curing and all percentages of replacement of OPC with SDA. The control split tensile strength value rose to 1.34N/mm2 at 90 days and 1.61N/mm2 at 150 days whereas the greatest 90 and 150-day values were 1.10N/mm2 and 1.51N/mm2 respectively for OAC and 1.29N/mm2 and 1.70N/mm2 respectively for SC. The 28-day values for FC were comparable to the control values for 5% and 10% replacement and increased rapidly to exceed the control values at 90 and 150 days. Therefore, OPC-SDA blended cement concrete with SDA obtained from FC could be used for all civil engineering works at 5-10% OPC replacement while OPC-SDA blended cement concrete with SDA obtained from FC at 15% OPC replacement and with SDA obtained from OAC and SC at 5-10% OPC replacement could be used for low strength civil engineering works where early loading of the structural members are not required. The models developed for FC, OAC, and SC methods were tested using t-test analysis and found to be adequate for predicting the split tensile strength values of OPC- SDA binary blended cement concrete at 28-150 days of curing and for 5-15% replacement of OPC with SDA, using SDA obtained from any of the three calcination methods.

Item Type:	Article
Uncontrolled Keywords:	Concrete, Split Tensile Strength, Rice Husk Ash, Furnace Calcination, Open Air Calcination, Stove Calcination.
Subjects:	T Technology > TA Engineering (General). Civil engineering (General) T Technology > TD Environmental technology. Sanitary engineering
Divisions:	Faculty of Engineering, Science and Mathematics > School of Civil Engineering and the Environment
Depositing User:	nwokealisi
Date Deposited:	18 Oct 2024 13:01
Last Modified:	18 Oct 2024 13:01
URI:	http://eprints.covenantuniversity.edu.ng/id/eprint/18525

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