Seismic Assessment of Existing Structures: The Influence of Joints on the Earthquake Resistance of Buildings
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
A study on the influence of joints in the context of seismic design on existing structures is performed based on the seismic retrofitting of an office building in Zurich. Joints separate the building into nine sections. It is assumed that these sections cannot be retrofitted as single sections and thus have to be connected to enable a sufficient retrofitting of the building by further measures.
The building is modelled and analysed with the FEM software package SOFiSTiK. Earthquake action is considered in the model using the response spectrum analysis method. Results are obtained for two versions of the model, one representing the current state with open joints and one reflecting the possible future state of a connected structure.
A comparison of the eigenfrequencies and displacements of the whole structure as well as of the principal stresses, the membrane forces in a section and the required amount of reinforcement in four exemplarily chosen core walls is performed. The displacements occurring at the edge of the joints in the topmost level of the model with open joints are larger than the existing joint width for most of the joints. Forces in the joints of the connected structure are used for the design of retrofit solutions. Strengthening of the core walls is necessary both in the current state with open joints as well as for the connected structure.
Retrofitting measures are inevitable for the building as the separated parts in the current state do not provide sufficient resistance and would collide under earthquake action. Without the basic measure of closing the joints, especially the sections with few and very eccentric core walls cannot be retrofitted with reasonable effort.
Place, publisher, year, edition, pages
Trita-BKN-Examensarbete, ISSN 1103-4297 ; 365
earthquake engineering, existing structure, finite element method, joint, reinforced concrete wall, response spectrum analysis, retrofitting measures, seismic design, seismic retrofit, SOFiSTiK, structural dynamics
IdentifiersURN: urn:nbn:se:kth:diva-125331OAI: oai:DiVA.org:kth-125331DiVA: diva2:639628
Subject / course
Structural Design and Bridges
Master of Science in Engineering - Urban Management
Karoumi, RaidPacoste, Costin