CEM III/B cement

CEM III/B is a blast-furnace slag cement under EN 197-1 in which ground granulated blast-furnace slag makes up 66 to 80 percent of the binder, with Portland clinker at 20 to 34 percent. The high slag content cuts the heat of hydration and densifies the pore structure, raising resistance to chloride ingress and sulfate attack, which is why it is specified for marine concrete in caissons, breakwaters, and gravity-base structures exposed to seawater. EN 197-1 caps chloride content at 0.1 percent by mass. Low-heat (LH) and sulfate-resisting (SR) variants suit massive marine pours where thermal cracking and seawater durability both govern.