A study on the Performance of Concrete prepared from Recycled Aggregates using Pullout Force Test

The rationale behind undertaking this project is to come up with a sustainable substitute for conventional normal aggregate material for the purpose of construction. In this case recycled concrete aggregate is used.
With the current levels of construction and demolished in Kenya there is increased availability of demolished concrete from construction.
This study seeks to determine how RCA can be used in concrete production and how they compare with normal aggregate in concrete. Using the waste concrete as RCA will conserves virgin aggregate, reduces the impact on landfills, decreases energy consumption and can provide cost savings; for sustainable development.
Also in this study seeks to evaluate how bond strength varies between RCA and normal aggregates.
A mix design for class 25 concrete was done. The aggregates both RCA and normal were assorted identically. Comparison on workability showed reduced workability in mixes containing RCA. However, compressive strength tests done for on all the RCA mixes showed little variation from the control mix.
The pullout force in normal aggregate samples was slightly higher than that in RCA samples. Also to note, larger bars offered more bond strength than smaller bars. Therefore, larger bar of more resistance to pullout force per unit circumferential area compared to smaller bars.
It is the analysis and discussion following these tests that form the basis upon which several conclusions and recommendations were made to wrap up the research.

Arthur Kamau Irungu.pdf2.45 MB