What is required to measure upward deformation on crossmember web top corners?

The requirement to measure upward deformation on crossmember web top corners involves taking measurements directly from the top corners themselves. This is important because the top corners are the points where deformation can be most accurately assessed, allowing for a clear understanding of any structural changes that may have occurred. By measuring from the top corners, the measurement captures the exact degree of upward deformation at those critical stress points.

Measuring from other locations, such as the base, side, or center, would not provide accurate data relevant to the deformation at the top corners, as these areas may behave differently under load or impact. Therefore, direct measurements from the top corners ensure that the assessment reflects the actual condition of the crossmember web at the points of concern.