Structure-form, as matrix of tectonic expression, is a concept formulated in this research from a transdisciplinary perspective. By means of association between architectural and structural engineering knowledges, the study was undertaken with the purpose of formulating analytical propositions that could reveal the design precepts that, in certain buildings, highlight the structure in their architecture. The first part of the research consists of a theoretical approach to the structure-form concept, contextualized by Architecture and Structural Engineering historical development, as of the rupture between their application fields from the eighteenth century onwards. The Museum of Modern Art of Rio de Janeiro (MAM-Rio), the Faculty of Architecture and Urbanism of the University of São Paulo (FAU-USP) and the Brasília Cathedral, were analysed according to the transdisciplinary categories proposed, in coherence to the approach of this research. Througout the work it was possible to confirm that the conceptual investigation, proposed in the first part of the research, turned out to be consistent as a theoretical basis to the analysis developed in the second part, in which the structure-form concept, deployed as a tenet in the design process, showed up not only evident but as their tectonic expression matrix as well. In addition to confirming expectations, the research broadened the field of investigation concerning Modern Architecture, and, possibly, Contemporary Architecture as well.