Environmentally and Economically Efficient Use of Coal Ash in Mortars with Thermal Conductivity Performance for Buildings | Chapter 5 | Engineering Research: Perspectives on Recent Advances Vol. 11

A research work was carried out to study the effect of the substitution of sand by coalash in masonry mortar from an energy efficiency point of view. Sand, a natural mineral, is rapidly depleting due to the developmental boom in India, causing a wider demand-supply gap. On the other side, a huge accumulation of legacy ash in Indian thermal power plants is causing serious environmental threats. To address these issues together, two types of conventional mortar grades, marked as MM-3 and MM-5 as per IS 2250, were studied, and the effect of stage-wise replacement by different substitution ratios (SR) of sand by coalash ( flyash and bottomash separately) on physical parameters as well as thermal parameters were recorded. Fly ash and bottom ash with lime dust and marble dust combinations were also tested as 100% sand-free mortars. Besides satisfying permissible strength criteria as per the Indian Code provision, the thermal conductivity value was found considerably lower than that in the conventional mortar mix. From the experimental results, it was observed that both the MM3 and MM5 grade mortars could be produced at 60% SR by fly ash and bottom ash separately, and corresponding reductions in thermal conductivity values were 69% and 54% respectively, compared to conventional mortar. As regards sand-less mortar for both the grades reduction to the tune of 57% was observed in the corresponding thermal conductivity value. Overall heat transfer co-efficient (U-value) for both side plastered and rendered brick masonry wall panel was found to be reduced by 15.58%, while a comparison was made between the conventional mix of MM5 grade and the corresponding 50% fly ash substituted mix. Thus, such ash blended mortar mix appears to be quite beneficial in building envelope application for lowering the overall cooling demand in building, besides utilizing the coal ash to the largest extent and saving natural mineral sand from rapid depletion. The proposed substitution of sand by coalash in building envelope construction application is also economically and environmentally advantageous.

 

Author(s) Details

Avijit Ghosh
CSIR-Central Glass & Ceramic Research Institute, 196, Raja S.C. Mallick Road, Kolkata-32, West Bengal, India.

 

Please see the book here :- https://doi.org/10.9734/bpi/erpra/v11/6283