Abstract:
This research work reports the results of self-compacting paste (SCP) systems using SRMs like ASTM class F fly ash and powdered silica fume as 10% by mass replacement of cement. The role of hemi-hydrate and anhydrite in such systems was also explored. In modern concretes including HPC and SCC all of cement is not intended to get hydrated which encourages use of SRMs. Replacement of cement due to SRM presence indirectly encourages friendly environment by reducing the cement content which is a major cause of air pollution in the form of CO2 emissions.
The parameters studied included Particle Characterization, Water Demand, Setting time, Flow Response using mini-slump Hagerman’s cone, Flexural and Compressive Strength response, Micro-structural Studies, Calorimetric studies and slump retention issues of SCP systems.
The maximum strength at 28 days is obtained for the formulation containing 10% replacement of silica fume. The SP demand to achieve the target spread was least for SCP formulation containing HH (hemi-hydrate). The flow of the formulations with incorporation of FA as 10% replacement of cement shows an increase in spread with increasing mixing time. If the paste system is allowed to rest for prolonged time, flow decreases. Moreover, the compressive strength of self-compacting paste systems at 28 days of the paste systems increases with an increase in the mixing time.