Research Seminar, May 23 2019:
Industrialized construction of multistory reinforced concrete wall buildings has become a common practice in Latin-American countries such a Colombia and Peru. An important feature of this structural system is that architectural spaces are also bounded by the structural walls, which reduces the time of construction and the related cost. Structural engineers have pushed the usable limits of the structural walls by further reducing their thickness over the years. This trend has resulted in large unbraced length, increasing the slenderness ratio of the wall at the critical section. When portions of these thin wall sections area subjected to compressive strains, the risk of concrete crushing and/or lateral instability arises. Additionally, given the reduced amount of reinforcing steel used, and the fact that non-ductile welded wire meshes are the main type of reinforcement used, some walls cross-section geometries might prevent fulfilling some typical design hypothesis. This presentation offers a summary of the findings of two and a half years of research in Colombia and Switzerland regarding the seismic resistant behavior of thin-walled buildings. Mechanical analyses, as well as numerical and laboratory experiments help understand the limits of the system in terms of the number of stories. A discussion on the proposals presented for a building code change in Colombia close the session.
Carlos Arteta is an Assistant Professor at Universidad del Norte in Colombia with a PhD in Structural Engineering from UC Berkeley (2015). He is the co-founder of the recently created CEER - Colombian Earthquake Engineering Research Network, an association between public and private universities to actively reduce the seismic risk in Colombia. His main research interest is focused on the selection and modification of ground motions for performance-based earthquake engineering, as well on the study of the assessment of the seismic vulnerability of reinforced concrete systems.