Brent Anderson, P.E., is the Moisture Control Solutions Team Leader at Structural Technologies. He serves on ACI 332 Residential Concrete and previously served on ACI 515 Protective Coatings for Concrete. Brent can be reached at banderson@structuraltec.com.
In the design of concrete structures, where concrete slabs and walls are used as the environmental barrier, water leakage is a concern. In well consolidated, normal weight concrete, high pH components within the cement/gel paste react with iron on the steel surface and resist corrosion from actively occurring around the steel. This is called “passivation.” …
Monolithic concrete with a compressive strength in excess of 3500 pounds per square inch (psi) is watertight, except at any irregularities in the structural element. Typical locations where irregularities occur include overhead decks, floors, and walls that have cracks, honeycombs, joints, mechanical/electrical penetrations, and form-tie supports. …