Inspection of Steel Structures

Is independent inspection of steel structures really necessary?

Previously a belief was common that inspection of steel structures is an unnecessary extra cost. Sometimes structural engineers acted as if the drawings are the final product. For structural steel fabricators "inspection and testing" in many cases was equivalent with taking X-ray films of a certain percentage of the welds. Among welders two weld categories were observed: "X-ray welds" and other welds.

We would like to state that a well-planned inspection and testing contributes not only to a correct and safe structure but also to an economic and optimal production.

The issue of quality has come to be of great interest within the building trade in recent years, not least within steel construction. There are several reasons for this:

  • The regulations and rules of today allow a higher utilization of steel, welds and bolted connections than before, which among other things lead to less reserves for erroneous workmanship

  • The regulations and rules of today also lead to a more qualified use of material. The requirements are closely related to the actual conditions through a number of different strength and toughness classes, workmanship classes, weld classes, classes for bolted connections etc. This may increase the risks for erroneous workmanship and with perhaps graver consequencies

  • Today high-strength structural steels are used with higher carbon equivalents and even QT-steels, which may put higher demands for correct treatment in bending, welding etc.

  • New weld processes are used with higher productivity but which may lead to an increased risk for serious weld discontinuities from incorrect application

  • Structural steel design of today is often more advanced, which may lead to increased sensitivity to defects and more serious consequencies of even a minor error

  • The hard competition of today leads to a search for cost reductions, which may not always go hand in hand with the quality requirements

  • Very experienced craftsmen are not so common anymore, risk of failures due to the human factor has increased

  • Demands for long service life and the concept of life cycle costs nowadays catch more attention. The service life with respect to fatigue as well as corrosion is highly dependent upon the workmanship and quality of the execution of steel structures.