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Volume Title: ICASGE2023

DOI: ICASGE-STA

¹Nour Mohamed El-Heweity ; ²Hesham ZeinElDin; ²Hamdy AbouElfath; ³Mostafa Shawky Ramadan; Nour Mohamed El-Heweity; Mostafa Shawky Ramadan

¹Structural Department, Faculty of Engineering, Alexandria University

²Structural Eng. Department, Faculty of Engineering, Alexandria University

³Structural Eng. Department, Faculty of Engineering, Alexandria University.

There are many existing RC buildings that have been designed according to earlier versions of code provisions or subjected to damage caused by earthquakes. These buildings might be in need of seismic strengthening by adding buckling-restrained braces (BRBs). Steel BRBs have good capability of improving the strength, the stiffness and the energy absorbing capacity of structures. However, they are prone to producing high levels of residual lateral drifts after strong earthquakes and this may make buildings appear unsafe to residents and can need costly repairs or complete demolition of the structure.
Recently, shape memory alloy (SMA) BRBs have received substantial interest because of their promising potential in controlling the residual lateral drifts after earthquake events. This study evaluates the seismic strengthening of a 6-story RC-building using hybrid SMA-steel BRBs. Seismic evaluation in this study has been carried out by static pushover analysis and time history earthquake analysis. Ten ground motions with different PGA levels are used in the analysis. The roof-drift, the story drifts amd the residual drifts along with the brace ductility ratios are used as the basis for the seismic performance evaluations. The results obtained in this study indicate the effectiveness of the proposed hybrid bracing system in improving the seismic performance of the strengthened RC frames.

Roof drift; Story drift; Buckling Restrained Brace; steel; SMA; Earthquake; pushover; dynamic analysis; Strength

Structural Analysis (STA)