What would happen if the silica percentage is higher than 25% of the total weight of the Portland cement?
Allow me to qualify my answer first. When mixing cement water, in the process and as it dries hardens, air pockets tend to form inside the concrete. Air pockets are like those holes that are inside the cheese we see when we cut it. Concretes could also tend to form air pockets as it dries up firms up. Those air pockets could WEAKEN the concrete, because of the spaces inside. Now, the function of silicon dioxide is it minimize those air pockets tends to make concrete stronger.
