@inproceedings{c290b37e53b649aa9edd0c4bf58506c2,
title = "Seismic strengthening of rc t-beams through flange post-tensioning with anchorages by bonding",
abstract = "One of the most common reinforced concrete (RC) structural systems are the ductile moment resisting frame structures. Although this structural system is recommended for buildings in seismic prone regions, some deficiencies have been observed in such buildings subjected to significant seismic events. Hence, the aim of the present study is to present a research study on the development of strengthening solutions in order to reduce the damages in ductile frames. The intervention proposed herein is strengthening through post-tensioning with anchorages by bonding. The performance of a strengthened T-beam, referred as specimen CB4, is discussed in this paper. The length of the beam represented 1/3 of the beam{\textquoteright}s clear span. The specimen aimed to represent the length between the beam-column joint and the contraflexure point of the beam under a combination of cyclic loading with gravity load. Two prestressing steel strands (Y-1860-S7-15.7) were installed in the flange region of beam CB4. Strands were fixed by mechanical anchorages at the end near the column and anchorages by bonding at the beam span. The beam CB4 behaviour, including residual deformations, residual stiffness, cracking pattern and energy dissipation, is compared to the reference beam (i.e., un-strengthened beam with identical cross section and reinforcing details – specimen CB1). Both specimens underwent a loading protocol that considers the presence of gravity load simultaneously with the cyclic loading. The obtained results show that beam CB4 suffered less damages, had lower residual deformations and dissipated more energy than beam CB1. As a result, beam CB4 would need less recovery/repair time after a seismic action when compared to the intervention needed for repairing beam CB1. Application of this strengthening solution increases the resilience of existing ductile moment resisting frame structures for earthquake actions.",
keywords = "Anchorages by bonding, Damage limitation, Post-tensioning, Resilience, Strengthening",
author = "Helisa Muhaj and Carla March{\~a}o and V{\'a}lter L{\'u}cio and Rita Gi{\~a}o",
note = "Publisher Copyright: {\textcopyright} F{\'e}d{\'e}ration Internationale du B{\'e}ton (fib) – International Federation for Structural Concrete.; 2021 fib Symposium of Concrete Structures: New Trends for Eco-Efficiency and Performance ; Conference date: 14-06-2021 Through 16-06-2021",
year = "2021",
month = jun,
language = "English",
series = "fib Symposium",
publisher = "fib. The International Federation for Structural Concrete",
pages = "1259--1268",
editor = "E. Julio and J. Valenca and Louro, {A. S.}",
booktitle = "Concrete Structures",
address = "Switzerland",
}