In this on-site video, Concrete Science investigates three dramatically different structures affected by fire—a basement with exposed rebar, a slab under collapsed apartments, and a shallow residential foundation. Learn how forensic testing, petrography, and expert judgment guide decisions on what can be repaired and what must be rebuilt.

Concrete structures often survive fires better than steel or timber but can still suffer spalling, cracking, and strength loss from prolonged heat exposure. This paper examines fire-induced concrete damage and highlights assessment methods like pulse velocity testing, rebound hammer tests, and petrographic analysis. A case study of a fire-exposed residential foundation demonstrates that with proper evaluation, targeted repairs can restore structural integrity without full demolition, offering a cost-effective rehabilitation approach.

The definition of petrography is the branch of science concerned with the description of rocks especially by microscopic study. We, at Concrete Science, use petrography as a baseline for examining the concrete or construction material and/or the sand and gravel.