Latest results from the seismic category I structures program

With the use of scale and different size models, the Seismic Category I Structures Program has demonstrated consistent results for measured values of stiffness at working loads. Furthermore, the values are well below the theoretical stiffnesses calculated from an uncracked strength-of-materials approach. The scale-model structures, which are also models of each other, have demonstrated scalability between models. The current effort is to demonstrate that the use of microconcrete and other modeling effects does not introduce significant distortions that could drastically change conclusions regarding prototype behavior for these very stiff, shear-dominated structures. (orig.)