1. What is the difference between a pozzolanic and a cementitious material? How does an admixture reduce soil plasticity index? What is happening to the clay particle so that the

plasticity index of the clay is reduced? Why are blast furnace slag and fly ash typically used as co-admixtures? Why is Class C fly ash generally a better admixture than a Class F fly ash? Would a Class F fly ash be effective for reducing clay plasticity? Why or why not? Remember than a clay is an aluminosilicate material.