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ackolay@iitk.ac.in, bjmr5@lehigh.edu, ctmm3@lehigh.edu, dswa313@lehigh.edu, eseq213@lehigh.edu Keywords: real-time hybrid simulation, large analytical substructure, computational simulation, nonlinear damper, seismic, braced frame.
Introduction Real-time hybrid simulation (RTHS) is a reliable and affordable alternative to more expensive shake table testing for simulation of seismic effects in civil infrastructure systems with loading rate dependent behaviour.
The buckling restrained diagonal braces were modelled using a nonlinear truss element with isotropic and kinematic hardening in order to capture the proper hysteretic behaviour of the braces.
The seismic masses based on the dead load within the tributary seismic area were lumped at the columns of the braced bay perimeter frame.
Case study of A 40-Storey buckling-restrained braced frame building located in Los Angeles.

The article presents partial results of a theoretical and experimental analysis of the behaviour of a frame span with a diaphragm discretely connected by means of rubber bearings and cross bars.
A-shaped), or by special stiffening structures (steel ropes or pipes diagonally bracing articulated joints of columns and girders) embedded in some “frame” spans to provide the required stiffness of the load-bearing structure.
The stiffness, static and dynamic characteristics of a frame structure with articulated “column-girder” joints: in the case of reinforcement by means of embedded thin-wall reinforced concrete diaphragms, the columns and girders with diaphragms are mutually discretely interconnected by means of contact rubber bearings.
The issues of seismic loads and the response of buildings to the effects of natural, technical and induced seismicity are presently subject to intensive research worldwide, not only in buildings situated in areas of increased natural seismic activity, but mainly exposed to the growing traffic and building activity volumes, both overground and underground, and in buildings suffering from technical and induced seismicity [2].
The displacements of the diaphragm in the transverse direction will more likely be applied in the horizontal seismic excitation of buildings or in the case of wind effects in tall structures.

Especially on the steel concentrically braced frame(CBF), the viscoelastic energy dissipation brace that as first seismic fortification lines can bearing more earthquake force and protect the buildings effectively.
According to specific stipulations of displacement limit in related code, quantization of aseismic behavior targets in this paper is shown in Tab 2.
Aseismic behavior targets of steel frame structure seismic fortification level performance level of structural Fully working basic working endanger life the first level(frequent earthquakes) A the second level(design earthquakes) B A the third level (rare earthquake) C B A Performance objective A: the basic seismic fortification target is the same with "Code for seismic design of buildings", that is,"no damage under frequent earthquakes,repairable under design earthquakes and no collapse under rare earthquakes".
The material of beam and column is steel(NO.Q235) ,and floor is reinforced concrete of C30.
Analyse results we can find, the control effect of method 3 is the most uniform, each layer stiffness arranrement of structure is the most reasonable.

Previous researched were studied methods to efficiently secure stiffness of vertical elements (column, wall) for efficient vertical displacement control in super tall buildings[1,2].
All external columns densely positioned or external wall with minimal opening resists all lateral loads, creating behavior of empty tube[8,9].
Design Model[mm] System Behavior Comparison of Lateral Displacement.
But Floor brace system shows gradual distribution because there is no concentration of story stiffness.
The brace effect on capacity of controlling lateral displacement was analyzed.

Experimental Study of Reinforcement Effect of Injured Frame Joints Under Different Axial Compression Ratio Mingxin Fang 1a, Zhiyong Yang 1, Zhengfei Chang 1,2, Shunhui Liu 1, Gang Wang 1,2 1School of Civil Engineering and Architecture, Wuhan University of Technology, 122 # Luoshi Road, Wuhan, Hubei, R.P.China, 430070 2ShenZhen YJY Building Technology Co., Ltd, Houhai Building, Houhai Road, Nanshan District, R.P.China, 518054 aE-mail: fmx126@163.com Keywords: Frame joint, Axial compression ratio,Carbon fiber reinforcement, Seismic behaviour Abstract: In this paper, reinforcement effect of the seismic performance of injured flat cross-shaped reinforced concrete frame joints under different axial compression ratio are analysed systematically through experiment.The research focuses on the relationship between the effect of reinforcement with carbon fiber and axial compression ratio.
The reinforcement by CFRP doesn't have significant effect on its ductility and stiffness degradation.
Seismic Behavior of As-Built, ACI-Complying, and CFRP-Repaired Exterior RC Beam-Column Joints.Journal of Composites for Construction, Vol. 15, No. 4, July/August 2011, pp. 522-534
Seismic response of RC frames retrofitted with steel braces or walls.
Seismic behaviour of non-seismically detailed interior beam-wide column joints – Part I: Experimental results.

Significant number of reinforced concrete building frames executed in the ‘50’s-60’s in Europe need seismic upgrading.
Buildings are in the 2-4 floors height range and depend on moment-resisting behavior for earthquake resistance.
Seismic performance of the r.c. frame The floor diaphragms have been modeled using equivalent cross-bracing.
The pushover results of the 3D model revealed very different behavior of the two principle directions (Fig. 2).
This is a general problem with bracing system added to r.c. frames, and solutions for the interface have been developed [13, 14, 15].

To ensure the seismic safety of hybrid structures, model tests or computation simulations are indispensable to acquire the knowledge and predict the behavior under earthquakes.
The bilinear kinematic model is used to simulate the hysteretic behavior, which is the default setting in PERFORM-3D.
It is widely acknowledged that the confining effect on the compressive behavior of core concrete in circular CFST columns is very significant.
For the coupling beams with the span-to-depth ratio less than 2.5, shear hinges are added to simulate the behavior after shear yielding.
The modified Takeda model [4], accurately reflecting the main characteristics of shear behavior, is used for shear material.

- The behavior of composite joint is strongly different with respect to the all steel solution; it can be observed a large increase of both stiffness and resistance.
Dubina, Seismic response of composite structures including actual behaviour of beam-to-column joints, Composite Construction Steel Concrete. (2006)V:708–17
Doneux, Seismic design and performance of composite frames, J.
Simões, L. da Silva, Cyclic behaviour of end-plate beam-to-column composite joints.
Castiglioni, Behavior of exterior partial-strength composite beam-to-column connections: experimental study and numerical simulations, J.

The Finite Element Analysis of Effect Factor about the Shear Behavior of Cold-formed Steel Composite Wall Xu Chao, An yuhua, Bai Aihua Jilin Institute of Architectural and Civil Engineering ,Changchun china ,130118 Keyword: cold-formed steel composite wall,parametric analysis,nonlinear finite element analysis Abstract: This paper adopts the finite element method to study the shear resistance of the first floor cold-formed steel composite walls in six stories residential structures, plastic shell element is used, materials nonlinearity and geometric large deformation are considered.
The screws connecting sheathing and frame are modeled through coupling methods.
Analyzing the influence of factors such as stud spacing，Brace and rigid bracing's establishment，component wall thickness to the shear behavior of cold-formed steel composite wall， these dates can provide certain theory for the actual project.
This paper mainly researches the shear behavior of cold-formed steel stud composed wall basing on Code for seismic design of buildings（GB50011-2001）and technical requirement for low-rise buildings with light-weight steel framing（JG/T182-2005）. the shear behavior of it can be affected by the martial of panel、stud spacing, brace and rigid bracing's establishment、component wall thickness and so on.
Study on the Shear Resistance of Light-Close Steel Column Wall.

This paper studies seismic behavior of concrete-filled square steel tubular column-to-beam connection with through diaphragm, which is popular in Japan, but rarely used in China.
Experimental studies on seismic behavior of concrete-filled steel square tubular column and steel beam joints under cyclic loading[J].
Experimental study on seismic behavior of connections composed of concrete-filled square steel tubular columns and steel-concrete composite beams with interior diaphragms [J].
Seismic behavior of composite concrete filled steel tube column-wide flange beam moment connections[J].Journal of Structural Engineering,2004,130(2):223~232
Strength and Behavior of Frames with Concrete Filled Square Steel Tubular Columns Under Earthquake Loading [C].