Concrete is prone to a variety of issues that may arise from poor construction or standard weathering. Many defects can be avoided by proper mixing and placement, but others remain likely to occur within a typical service life. Regular inspections are therefore recommended to detect and document conditions over time. If structural issues arise, a professional engineer should be retained to investigate, diagnose, and specify repairs. Typical problems with concrete are described in more detail in this article but also summarized below.
Typical Concrete Problems and Their Causes
Poor concrete mix design or vibration techniques can result in honeycombing—when coarse aggregate is exposed without sufficient surrounding morta—or bugholes, in which a lean mix displays small holes on the surface. Disintegration and its milder version, scaling, are forms of concrete fragmentation into its constituent parts that can be minimized with proper proportions and placement. These defects promote further infiltration of water and long-term damage from freezing and thawing.
Weathering or alkali-silica reactions can cause hairline surface cracking and may be accompanied by efflorescence (mineral residues from evaporated water). While efflorescence itself is not a structural defect, it is an indicator of water seepage that could lead to further deterioration. Minor cracks can give way to more serious structural fractures, indicating settlement, loss of supporting fill material, and potential for failure. Cracks larger than 0.25” wide should be further investigated and repaired.
Abrasive erosion (rubbing of aggregate on the concrete surface, causing a worn appearance) or cavitation erosion (pitting that results from differential pressure impacts of a fluid onto the surface) can affect the integrity of hydraulic structures over time. Spalling, or flaking of concrete, occurs due to external impacts or internal stresses that can vary in scale. Shallow “popouts” are small conical spalls that may not be serious, but larger spalls indicate structural damage.
Of course, when you use Cor-Tuf UHPC, you avoid these issues.