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A simplified model reproducing the behaviour of steel plate shear walls was developed and implemented in the numerical model of the R/C frame.
Beams and columns were modelled using one-dimensional elastic elements with inelastic behaviour concentrated at the edges in plastic hinge regions (Giberson model) and defined by appropriate moment-curvature hysteresis rules available in the code Ruaumoko library.
The DCR values reproduced quite well the behaviour observed in terms of inter-story drift, showing values greater than one due to lack of ductility detailing.
Maximum DCR values for the columns of the bare frame for different seismic intensity levels.
The effects of steel plate shear walls on the seismic response of a non-ductile five-story R/C frame were assessed using nonlinear dynamic analyses and two story-wise distributions of the steel panel thickness were examined.

Also parameter e1 is used to study the effect of eccentricity of the middle node on the frame behavior. e1 is introduced by Eq. 4 [2]: (Fig. 2) (4) The frame stiffness is reduced against the lateral loads when the middle node moves to the corner of the frame.
The interesting point about this type of brace is that three members of the left OBS and the right hand side column would be under pressure and three members of the right OBS and left hand side column would be in tension when the lateral load is applied to the side of the frame [2, 4].
Columns section, braces section and beam section in all models are HE120B, 2UPN120/10 and IPE270 respectively.
Columns section, beam section and braces section are HE120B, IPE270 and 2UPN120/10 respectively.
Estekanchi: Seismic Behavior of Off-Centre Bracing Systems, Journal of Constructional Steel Research, v51, n2, p 177-196, 1999 [3] H.

Study on Mechanical Behavior of the Key Components of High-level Transfer Frame-shear Wall Structure with Steel-lead Viscoelastic dampers Ling Yi 1, a, Congxiao Wu 2,b 1 JiangXi University of Science and Technology, GangZhou,341000, P.R.China 2School of Civil Engineering, Guangzhou University, Guangzhou 510006,P.R.China ayiling76326@163.com, bwu-congxiao@163.com Keywords: Energy dissipation, High-level transfer, Transfer beam, Mechanical behavior Abstract.
Based on the limited demand of transfer beam sectional dimension of tall building structure with transfer story in Technical Specification for Concrete Structures of Tall Building, a high-level transfer frame-shear structure with steel-lead viscoelastic dampers is presented for simulating the mechanical behavior of the key components effect with consideration the transfer beam depth with 1/6, 1/8 and 1/10 calculation span.
In order to prove the seismic performance of the new system, Nonlinear time history analysis under frequently occurred earthquake and rarely occurred earthquake of the high-level transfer structure with the steel-lead viscoelastic dampers, buckling-restrained braces, lead-viscoelastic dampers or steel-lead viscoelastic dampers are conducted, and the results show that the proposed structural scheme is feasible, and the original structural seismic behavior could be obviously improved on account of the adoption of the system[4][5].
In the paper, a high-level transfer frame-shear structure with the steel-lead viscoelastic dampers is studied for simulating the mechanical behavior of the key components effect with consideration the different transfer beam depth.
(3) The internal forces of frame-support column are not influenced to change the transfer beam depth

The effect of pre-tension applied to the bracing members is also examined through the brace axial strain and lateral load relationship.
This behavior is based on the characteristics of the quasi-linear motion mechanism.
Therefore, the lateral stiffness of the test specimens is dependent only on the damper system.
Out-of-plane movement of the frame was prevented at the column tops.
Chang: Seismic Demands on Steel Braced Frame Buildings with Buckling-Restrained Braces,” Engineering Structures, 25 (2003), p.655-666

The material is steel, but those using lead or friction pad can exhibit similar behavior.
As depicted by Figure 3(b), the parameters affecting control are the mass, elastic stiffness of the frame and brace, and damping and stiffness of the damper.
The former is a ratio of the dissipater loss stiffness (defined when peak force is below the relief load) to the frame elastic stiffness, and the latter is a ratio of the brace elastic stiffness to the frame elastic stiffness.
The former is a ratio of the dissipater loss stiffness to the frame elastic stiffness, and the latter is a ratio of the brace elastic stiffness to the frame elastic stiffness.
That is, one could size the damper and brace such that the ratios of their stiffnesses to the frame story stiffness satisfy the ratios determined from the SDOF approach explained above.

The seismic behavior of this new structure was analyzed.
Effect of wind turbines to seismic behavior of structure was obtained and the seismic feasibility of the new structure was preliminarily analyzed.
The model is a 20-floor steel braced-frame structure.
(3) The bottom stiffness should be properly strengthened and local part of structure, like wind turbine bracing and so on, should be optimized.
References [1] Xuejun Zhou, Lu Chen, Hui Qu, Effects of layout of braces for multistory and high rise steel structures on lateral stiffness of frames, Steel structure, 66 (2003)51-54.

The yield drift ratio for moment frames (=1%), special truss moment frames (=0.75%), eccentrically braced frames (=0.5%) and concentrically braces frames (0.3%) is assumed to be constant for all practical design purposes [40].
Replaceable links with gusseted brace joints for eccentrically braced frames.
Effect of column stiffness on braced frame seismic behaviour.
[23] Lai, J.W., Mahin, S.A. 2015.Strongback system: A way to reduce damage to construction in steel –braced frames.
Quasi-static cyclic behaviour of controlled rocking steel frames.

Ricles et al. [2] introduced the application of post-tensioned strands in the beam to column connections in which the gap opening in the contact surface of the beam-column connection provides the inelastic behavior and the strands provide the self-centering behavior.
The application of friction-based energy dissipating devices in steel structures dates back to 1982 where Pall et al. [5] used them in the braced frames to absorb the seismic energy.
To study the behavior of the steel MRFs with RSFJs, a prototype frame is considered.
Ricles, “Behavior and design of posttensioned steel frame systems,” J.
Marsh, “Response of friction damped braced frames,” J.

Information about the connections between beams and columns is not available, but it is likely that, because of the construction’s date, they do not have ductile behavior or anyway they do not perform plastic bending moments in the beams or columns in case of earthquake.
The use of bracing structures has been recently studied by authors in other seismic situations [1] [2].
The seismic protection is obtained both for low-intensity earthquakes, for the relevant bracings stiffness, and for high-intensity ones, for the chance to dissipate energy in the connections between bracings and r.c. frames.
Biaxiality effect on the energy dissipated by elastoplastic base-isolators.
Mechanical behavior of full unit masonry panels under fire action.

Steel adding layer technology has the advantages of light self–weight, good seismic behavior, easy construction, etc.
It’s adopting rigid connection between the steel frame column and original structure.
Then get horizontal seismic effect through SRSS method.
This is due to the obvious mutation--the stiffness of the steel frame structure is small, while the stiffness of the masonry structure is relatively large.
Finite element analysis of seismic behavior of RC frame strengthened with carbon fiber sheet [J].