What happens to concrete, brick, and masonry items when heated?

When concrete, brick, and masonry items are subjected to heat, they do indeed expand, but this expansion occurs at different rates. This is primarily due to the composition of the materials; for instance, concrete may contain aggregates that have different thermal expansion coefficients compared to the cement matrix, and bricks can vary significantly in moisture content and mineral composition. This differential expansion can lead to stresses within the material, potentially resulting in cracking or other forms of damage under extreme heat conditions.

Understanding this behavior is crucial during fire investigations, as it helps in assessing the effects of heat on structural components. When evaluating a fire scene, investigators must recognize that the structural integrity of these materials can be compromised, but the answer focuses specifically on the expansion behavior rather than immediate failure or disintegration.