Some Recent Developments in Structures Fitted with Buckling Restrained Braces (brbs)

Resumen El presente trabajo muestra los resultados de varios estudios numéricos y experimentales que han realizado los autores con la finalidad de cuantificar los beneficios de los Contraventeos Restringidos al Pandeo (crp) al ser introducidos en estructuras de edificios. Los estudios experimentales más relevantes incluyen pruebas, en mesa vibradora, de modelos de acero y concreto reforzado. Dentro de los estudios numéricos, se incluye: 1) la propuesta de un método de diseño, 2) una evaluación de los benefiHéctor Guerrero Bobadilla Engineering Institute National Autonomous University of Mexico hguerrerob@ii.unam.mx

Introduction s) are typically and an unbonding material to prevent direct interaction between the where fi is the frequency after the ith test and fini s) has a higher level of stiff s) has s help prevent s help control lateral    Shaking table test of one-story one-bay frames working in parallel duced by the unam First, the frames were tested alone, that is, without any In the third test, the conventional brace was replaced by a fourth test, two s, respective s) had s had higher damping level goes down as the number of conclusion is attributed to the fact that the axial deformations of s are reduced as the number of model was proposed allowing designers to estimate the damping level

Numeral studies
A method for the seismic design of structures with BRBs First, a method for the seismic design of structures equipped with s and a braced pinned connected frame; and 2) the dynamic behavior of

Residual displacement on structures equipped with BRBs
) on structures tends To understand the residual displacement demands on structures equipped with s, dual oscillators were therefore primary) structure without s plus the capacity curve provided by the placement in structures equipped with s is closely connected to the I, s is theo s have enough s because the s may be higher, as both the main

Conclusion
The main advantages of

Figure 1 :Figure 2 Figure 3 :
Figure 1: Components of a typical BRB.Image taken from: Héctor Guerrero Bobadilla and others, "Response to Seismic Sequences of Short-Period Structures Equipped with Buckling-Restrained Braces located on the Lakebed Zone of Mexico City."Journal of Constructional Steel Research 137, (2017): 37-51.

Figure 4 :Figure 5 :
Figure 4: Roof displacement in the model with BRBs when subjected to the SCT2-EW ground motion seen in the April 25, 1989 Mexico earthquake.Image taken from: Héctor Guerrero Bobadilla, and others, "Experimental studies of a steel frame model with and without buckling-restrained braces."

Figure. 6 :
Figure.6: Héctor Guerrero Bobadilla, Reinforced concrete model tested on a shaking table at the unam.Image taken from: Héctor Guerrero Bobadilla, Seismic Design and Performance of Hospital Structures Equipped with Buckling-Restrained Braces in the Lakebed Zone of Mexico City.PHD Thesis Dissertation, University of Manchester, UK, 2016.

Figure 7 :
Figure 7: Damping estimate for the reinforced concrete models.Image taken from: Guerrero Bobadilla, Seismic Design and Performance of Hospital Structures Equipped with Buckling-Restrained Braces in the Lakebed Zone of Mexico City.

Figure 8 :
Figure 8: Stiffness degradation estimates for the reinforced concrete models.Image taken from: Guerrero, Seismic Design and Performance of Hospital Structures Equipped with Buckling-Restrained Braces in the Lakebed Zone of Mexico City.

Figure 9 :
Figure 9: Maximum dynamic response for the model with SCT 100%.Image taken from: Guerrero Bobadilla, Seismic Design and Performance of Hospital Structures Equipped with Buckling-Restrained Braces in the Lakebed Zone of Mexico City.

Figure 10 :
Figure 10: Héctor Guerrero Bobadilla, Five one-storey one-bay frames tested on a shaking table.

Figure 11 :
Figure 11: Damping ratio for the tests on the one-storey one-bay frames working in parallel.

Figure 12 :
Figure 12: The dual structure subdivided into a moment-resisting frame and a braced pinned connected frame.Image taken from: Héctor Guerrero Bobadilla and others, "A Method for Preliminary Seismic Design and Assessment of Low-Rise Structures Protected with Buckling-Restrained Braces", Engineering Structures 123, (2016): 141-84.

Figure 13 :
Figure 13: The dual structure represented by a dual SDOF oscillator.Image taken from: Guerrero Bobadilla and others, "A Method for Preliminary Seismic Design and Assessment of Low-Rise Structures Protected with Buckling-Restrained Braces."

Figure 16 :
Figure 16: Cost evaluation of the six-story structure: (a) initial costs and (b) life cycle costs.Image taken from: Guerrero Bobadilla and others, "Evaluation of the economic benefits of using Buckling-Restrained Braces in hospital structures located in very soft soils."

Figure 17 :
Figure17: Mean maximum interstory drift ratios for the six-story frame subjected to the set 1 seismic sequences.Image taken from: Guerrero, and others, "Response to seismic sequences of short-period structures equipped with Buckling-Restrained Braces located on the lakebed zone of Mexico City."

Figure 18 :
Figure18: Mean maximum interstory drift ratios by case for the six-story frame subjected to set 1 seismic sequences.Image taken from: Guerrero Bobadilla, and others, "Response to seismic sequences of short-period structures equipped with Buckling-Restrained Braces located on the lakebed zone of Mexico City."

Figure 19 :
Figure 19: Simplified capacity curve for structures equipped with BRBs.Image taken from: Héctor Guerrero Bobadilla and others, "Residual displacement demands of conventional and dual oscillators subjected to earthquake ground motions characteristic of the soft soils of Mexico City, " Soil Dynamics and Earthquake Engineering 98, (2017): 206-21.

Figure 20 :Figure 21 :
Figure 20: Normalized residual displacement on structures equipped with BRBs.Image taken from: Guerrero Bobadilla and others, "Residual displacement demands of conventional and dual oscillators subjected to earthquake ground motions characteristic of the soft soils of Mexico City."

Figure 22 :
Figure22: Normalized residual displacement for positive post-yielding stiffness ratios.Image taken from: Guerrero Bobadilla and others, "Residual displacement demands of conventional and dual oscillators subjected to earthquake ground motions characteristic of the soft soils of Mexico City."

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tecture and a Master's and Doctorate from the National University of unam ly the lead researcher at the unam he has also served as interim director, academic secretary and repre and undergraduate programs at the unam orable mentions and one an award for best Master's thesis from the lines of investigation include the seismic torsion of buildings, the de tection of structural damage, passive and active control of structures, n tural en la unam unam, en donde ha ocupado cargos como Director posgrado de la unam

Recent Developments in Structures Fitted with Buckling Restrained Braces (brbs)
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