Describe what beneficial effects will occur for including SC

Describe what beneficial effects will occur for including SCM flyash or SCM slag (ggbs) in the concrete used for a thick mat slab (8 ft thick) that is placed for a building foundation 7.17 articular the heat generated and the subsequent strength of the concrete

Solution

Ans. Mixing of SCM certainly has many benefits such as increased strength, reduced permeabiltity , low heat of hydration , better sulphate resistance etc.
- during hydration C3S and C2S reacts with water which leads to the production of C-S-H gel and CaOH2. This CaOH2 causes many problems. The SCM reacts with this CaOH2 and produces cementitious gel and hence due to this we have more strength , less sulphate attacks. But remember this that rate of hydration with SCM is less and hence the increase in strength is seen only after 2-3 months. hydration reaction of water with SCM produces less heat of hydration as well. And hence we use many a time PPC or PSC in mass construction works.