Failure mechanism of concrete with partial replacement of incinerator bottom ash to cement

Abstract

Cement was a binder material that used in concrete industry. The cost production was very expensive due to the high global demand. Therefore, a new alternative was used to replace the cement in concrete which was bottom ash. The objectives of this study were to investigate failure mechanism and the fracture surface on concrete containing bottom ash, to observe the ability of bottom ash as a binder and properties of the concrete mix with partial replacement of bottom ash. Bottom ash shown some similar characteristic with the Ordinary Portland Cement based on the result of XRF bottom ash which was nearly similar compounds of Calcium and Silica. The control sample of 0 % was the best slump test with 45 mm for the true slump compare with 10 % of bottom ash which was 55 mm. Water absorption test was carried out to determine the capability and strength of concrete. From the results shows the percentage of water absorbed increases with increasingly of proportion bottom ash. The strength of concrete for compression test was done where the highest strength of concrete was control sample with 35.6 MPa and 27.5 MPa for 10 % of bottom ash that achieved the targeted. From scanning electron microscope image shows the failure of the 30 % bottom ash concrete with bond matrix C-S-H (calcium silicate-hydrate) particles lowest. 30 % of the bottom ash concrete was the largest crack compared with the other percentage caused by factors that were not sufficiently strong bind between the matrix causes a failure occurs.