Application of Contemporary Structural Building Codes to Antiquated Materials: Fid-Bau Portal

Application of Contemporary Structural Building Codes to Antiquated Materials

Paulson, Conrad

Numerous older buildings are frequently preserved, rejuvenated, or simply re-used for a new occupancy. These processes often include significant modifications to the structural systems, or, as a minimum, a contemporary assessment of the strength of the existing structural system to verify its suitability for the new purpose. For buildings that are in excess of 80 years old, structural elements may include cast iron columns, wrought iron beams, and structural clay tile arches. These structural systems and their materials are unknown entities to the contemporary structural engineer — and also unknown to contemporary structural design codes. As an example, old structural steel manufactured during the 1880s through the 1930s is sufficiently different from contemporary structural steel that it too should be considered obsolete and therefore not fully represented by contemporary materials specifications. This paper reviews selected properties of antiquated and obsolete structural materials in the context of contemporary structural design codes. This includes a contemporary assessment in terms of reliability. The reviews and comparisons are accomplished through the use of case studies, concentrating on buildings from Chicago in the period of the 1880s to the 1910s. Recommendations are made on how to work with antiquated systems and now-obsolete materials while using contemporary structural design codes.