Latin American and Caribbean Consortium of Engineering Institutions
Conference Track: Sustainable
Engineering
Keywords:
Wood Ash, Coal Fly Ash, partial replacement, mechanical properties,
optimum mix, cost savings
Contact Title:
Dr.
Contact First Name: D. V.
Contact Last Name: Reddy
University:
Florida Atlantic University
Web:
http://www.civil.fau.edu/faculty_staff.htm
Position:
Professor of Civil and Ocean Engineering
Country:
USA
Email:
dvreddy@oe.fau.edu
Paper Title:
Use of Fly Ash and Municipal Ash in Cost-Effective Structural
Concrete for a Sustainable Environment
Abstract:
Coal fly ash and wood ash, two waste materials, were added singly
to concrete mixes as partial replacement of the cement contents.
Mechanical property testing and cost analysis were carried out with
varying ash incorporation amounts. The objective of the investigation was
to determine the changes in mechanical properties and cost-effectiveness
of ash modification.
The mechanical tests carried out were as follows: Compressive
Strength Tests, Split-Cylinder Tensile Strength Testing, and Slab Testing.
The cost analysis comprised the determination of the cost of material for
each mix, with different percentages of the ash content.
The test results indicated that MSW bottom ash does not possess the
high-strength characteristics found in coal fly ash-modified concrete.
The cement altered municipal ash-modified concrete was relatively
weak, compared to the coal fly ash-modified concrete. When MSW bottom ash
is added as a 10-25% replacement of the total aggregate, the strength
values are comparable to those of unmodified concrete. This is a notably
important observation because it promotes the utilization of MSW ash in
applications where extremely high strengths are not needed.
However, the slab test results show that the strains experienced by
the MSW bottom ash-modified pavement are comparable to those that occurred
in the coal fly ash-modified slab. The results from the finite element
analysis compared well with and validated the experimental data, thus
proposing that both fly ash and municipal ash are effective in concrete.
This realization suggests that the both ash-modified mixes are reasonable
designs for highway pavement applications. Furthermore, by using the ash
as opposed to stockpiling it, environmentally sound disposal of the waste
can be achieved while providing a cost-effective material to the
construction industry.
Mailing Address:
Department of Civil Engineering
Bldg. 36, Rm. 216
Florida Atlantic University
777 Glades Road,
Boca Raton, FL 33431
Phone:
Authors:
Dr. D. V. Reddy