Chapter 16 - Problem Solving

Abstract

This chapter focuses on how to troubleshoot defects in concrete. When concrete with excessive water in the mixture is installed, it may have to be removed and replaced. A repair may not be feasible. If the damage is shallow, say, less than 1.5 in., a concrete sealer is one repair option. Bad design data can result in a host of concrete problems. This problem can affect any element of an installation or repair. Concrete slabs need to be equipped with expansion and contraction joints. If they are not installed, cracking is likely. Concrete can be damaged from chemical attacks. Sodium, magnesium, calcium sulfates, and salts that can be found in alkali soils and groundwater could cause expensive concrete damage. Moving water channeled by concrete structures can contain destructive elements. Abrasion from waterborne sand and rocks can extensively damage a concrete surface. Generally, the water must be moving quickly for this to be a significant problem. Cavitation can damage concrete when fast-moving water encounters discontinuities on the flow surface. When flowing water is lifted off the concrete surface, bubbling can occur. This creates a negative pressure zone.