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Flexural Behaviour Of Reinforced Concrete Elements Retrofitted Using External Unbonded Superelastic Shape Memory Alloy Bars, Yamen Ibrahim Elbahy

Electronic Thesis and Dissertation Repository

Steel reinforced concrete (RC) framed structures are seismically designed for safety, where the earthquake energy is dissipated through yielding of the steel bars. During strong earthquakes, high inelastic deformations are allowed to take place. This allowance results in significant residual deformations. Thus, following an earthquake, the structure might be deemed irreparable, requiring its demolishing and replacement. If the frame can be designed to regain its original shape following an earthquake, then the structure will be repairable. This kind of design can be achieved by using smart materials such as Shape Memory Alloys (SMAs).

SMAs have unique properties, which make them …

Seismic Performance Of Modular Steel Frames Equipped With Shape Memory Alloy Braces, Papia Sultana, Maged A. Youssef

Civil and Environmental Engineering Publications

The demand for modular steel buildings (MSBs) has increased because of the improved quality, fast on-site installation, and lower cost of construction. Steel braced frames are usually utilized to form the lateral load resisting system of MSBs. During earthquakes, the seismic energy is dissipated through yielding of the components of the braced frames, which results in residual drifts. Excessive residual drifts complicate the repair of damaged structures or render them irreparable. Researchers have investigated the use of superelastic shape memory alloys (SMAs) in steel structures to reduce the seismic residual deformations. This study explores the potential of using SMA braces …

Enhancing The Seismic Performance Of Steel Structures Utilizing Superelastic Shape Memory Alloys, Papia Sultana

Electronic Thesis and Dissertation Repository

Although conventional earthquake-resisting structural systems provide the life safety level during earthquakes, they experience significant structural damage when exposed to strong ground shaking that render structural retrofitting as uneconomical. Superelastic shape memory alloys (SMAs) can be used in steel structures to reduce the residual deformations due to their recentering capability, which can facilitate post-seismic retrofitting. The primary aim of this thesis is to enhance the seismic performance of both regular and modular steel structures using an optimum amount of superelastic SMAs material in terms of maximum inter-storey drift, residual drift, and damage scheme.

First, a simplified method based on pushover …

Prediction Of Local Seismic Damage In Steel Moment Resisting Frames, Papia Sultana, Maged A. Youssef

Civil and Environmental Engineering Publications

Steel moment resisting frames (SMRFs) are widely utilized as a lateral load resisting system. Their seismic performance is usually assessed by examining the maximum value of inter-storey drift (MID) of all floors. The accuracy of such assessment is debatable given the wide spread of values of MID at collapse that exist in the literature. In this study, a simplified method to define the failure inter-storey drift for each floor of a SMRF is proposed. The method was validated with the experimental and analytical studies by other researchers. Three- and ten-storey SMRFs were considered to further validate the proposed method. The …