ABSTRACT
This chapter explores the history of how theorists and designers learned how beams work, what factors need to be considered when assessing them, and how the development of new materials and analytical methods led to the ubiquitous and predictable section-resistant beam systems. There are two primary stresses that beams need to resist through their cross-sectional area and their material qualities: Bending and shear. One of the reasons beam theory and bending wasn’t as quickly understood scientifically as cables and arches is related to the difficulty of translating physical experiments to reliable mathematical models. Galilei Galileo distinguished between strength of a material versus strength of object. He also was able to confirm that the depth of a beam’s cross-section mattered in providing resistance to bending. Once cast-in-place concrete was used for beams, it made sense to also use it as the structural material that spanned between beams–eventually morphing together to become a unitary load-collecting structural element called a “slab.”.
