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Analysis of Seismic Vibration Reduction of Latticed Shell with Bucking-Restrained Braces Zhan Zhong Yina, Xiu Li Wangb School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, P.R.
An Idea of Seismic Vibration Reduction of Latticed Shell Given the multi degree of freedom and intensified natural vibration frequency of lattice shell, it is inapplicable to directly employ Kobori’s way of controlling frame construction.
Fig. 4 The Maximum Axial Force of Time-histories Under El Centro Wave the analysis of hysteresis behavior of BRBs under three-dimensional earthquake ground motion.
Hysteresis behavior is the major index indicating the capability of energy dissipation of the member or structure.
The members of the lattice shell employ column elements and the lattice shell is a statistically indeterminate structural system.

Introduction Double-tube BRBs with contact rings is a displacement-related damping with dissipative behavior.
Its dynamical behavior is related to many factors such as the restraint stiffness of the outer-tube, the space between outer-tube and inner-tube, the properties of the materials and so on[1-4].
Therefore, the paper designs the models of double-tube BRBs with contact rings by employing the general materials, experimental equipments and conditions in existence and carry out an experimental research on the dynamical behavior of these models.
The rigid frame and base are made of welded steel with high stiffness so as to ensure that much more accurate data can be collected.
References [1] Yamaguchi M., Yamada, and Matsumoto Y. et al: Full-Scale Shaking Table Test of Damage Tolerant Structure with a Buckling Restrained Brace, edtied by Journal of structural and construction engineering. 558: 189-196. (2002) [2] Kim J and Seo Y: Seismic Struchires design of loin-rise steel frames unth buckling-restrained braces, edtied by Engineering Structures, 26:5, 543-551. (2004) (in Chinese) [3] Uang Chia-ming, NAKASHI MAM asayoshi: The Practice and Research Development of Buckling Restrained Braced Frames(Ⅱ), edtied by Progress in Steel Building Structures. 7:2, 1-11. (2005) (in Chinese) [4] Tsai Keh-Chyuan, Hwang Yean-chih, Weng Chung-shing.

Gotthardt, Elastic Behavior: Superelasticity, In: K.H.J.
Andrawes, Experimental Flexural Behavior of SMA-FRP Reinforced Concrete Beam, Front.
Moradi, Seismic Response of Steel Braced Frames with Shape Memory Alloy Braces, Journal of Constructional Steel Research 67 (2011) 65–74. https://Doi.Org/10.1016/J.Jcsr.2010.06.006
Alam, Comparative Seismic Fragility Assessment of Buckling Restrained and Self-Centering (Friction Spring and SMA) Braced Frames, Smart Mater.
Khan, Seismic Performance of Deficient RC Frames Retrofitted with Sma-Reinforced ECC Column Jacketing, Innov.

This building, completed in 1930s, was designed without considering the effect of possible earthquakes which cannot meet the current seismic criteria.
Safety and seismic behavior are analyzed.
To obtain satisfactory behavior, it has to be retrofitted.
Analysis shows that the new shear walls are designed to improve the seismic performance of the frame by increasing its lateral stiffness and capacity.
Through addition of the shear walls, load can be transferred out of the frame and into the shear walls, bypassing the weak columns while increasing strength.

Device constitutive behavior was represented by a velocity-dependent law and model verification included explicit link spring/area settings to prevent silent unit-scaling of damper properties.
Beams and columns were modelled as frame elements, shear walls as shell elements, and slabs as membrane shells.
Chevron braces offer lateral stiffness but add bulk, so wall-mounted units were preferred for integration.
Effects of brace-viscous damper system on the dynamic response of steel frames
Effects of using different arrangements and types of viscous dampers on the seismic performance of intermediate steel moment frames.

Huge frame suspended structure lateral rigidity is worse，if adopt RC frame，it have lots of wet operation，long construction period，need a lot of formwork and scaffold；if adopt steel frame with brace，its have weak lateral rigidity，steel usage increased in order to guarantee structure stiffness[6][7].
Suspended structure system with huge concrete-filled tubular steel lattice column can overcome shortcomings of center tube suspended on one point and reliability of anti-seismic，huge concrete-filled tubular steel lattice column is axis force member, it no obvious shear lag effect which relative to bending members is center tube, it has more anti-side stiffness relative to shear structure is frame, it has more higher bearing capacity relative to RC frame，and lattice column has no stability problem as which has large section relative to steel frame column，so its can use properties of materials mechanical character more conducive.
Atudies on Seismic Properties of Mega-Truss-Suspended Steel Structures
A Study of Seismic Properties of Huge Frame Suspended Structure in Tall Buildings.
China civil engineering journal, 2007，40（3）:40-45 [7]Wang Chunlin,Lv Zhitao.Dynamic Behavior and Parameter Optimization of Core-Tube Suspension Structures.

To examine the effect of the sub-structural stiffness ratio changes on the effectiveness of the overall structure system, the ratio RD is defined and expressed as follow: (1) Where in Kmega is the mega-structure stiffness and is expressed as: (2) E is the elastic modulus of steel and I the moment of inertia of the mega-column.
For RD < 0.05, the structure exhibits “random or disorderly” response behaviors.
The relative mass ratio (RM) between the mega frame and sub-structures is also examined and defined as follow by Eq. (4): (4) Where Msub is the total mass of the sub-structures and Mmega is the total mass of the mega-frame.
Conclusion Through this study the seismic responses of MSCSS have been investigated.
[3] Li Tao, Zhang X.A, Wang Q.Q., (2011), “Control Characteristics of mega-sub controlled structure system with Friction Damper under Rare Earthquake”, Proceedings of the International Multiconference of Engineering and Computers Scientists 2011, vol II, IMECS 2011, March 16 – 18, 2011, Hong Kong [4] Lian Y D, Zhang X A, Cherry S. (2007), “Damping characteristics of friction damped braced frame and its effectiveness in the mega-sub controlled structure system”.

Multi-story buildings often use steel moment frames as lateral force resisting systems, because such systems would allow architectural flexibility, while providing the strength, stiffness, and ductility required to resist the gravity, wind, and seismic loads.
Experimental and Numerical Investigation of Beam-to-Column Connections in Steel Moment Frames Prone to Column Loss Scenarios 2D frame tested for column removal.
The results of the numerical analysis indicate that the model can be used to accurately replicate the behavior of the specimen and the failure mode in case of column removal.
Two-way frame system investigated for internal column loss [6] Influence of Beam-to-Column Connection Properties on Robust Response of Steel Moment Resisting Frames: Seismic Based Design and Robustness Strengthening Design of beam-to-column connections.
Fig.6 shows a very good correlation between the response of the FEM and AEM models, with the same initial stiffness, yield force, post-elastic behavior, and ultimate force and displacement.

The elastic effects of supporting structure and BRB were two key factors.
Buckling Restrained Brace (BRB) has good capacity of damping of vibration and absorption of energy in frame structure, but the application of BRB in reticulated shell is not widely at present.
The stiffness and natural frequencies of overall structure increase with lesser increment after setting BRB in upper reticulated shell and under detached columns.
An Analysis of Seismic Vibration Reduction of K6 Reticulated Latticed Shell by Means of Buckling-Restrained Braces [J].
Analysis of mechanical behavior and high-order mode of buckling-restrained bracing [J].

The results show that: with the stirrup ratios increasing, the short column with rectangle hoop, rectangle cross brace hoop and tic tac toe stirrups appear successively few inclined cracks and more vertical cracks; with the axial compression ratio increasing, more length of horizontal cracks extend to natural axis, more vertical cracks appear and appeared cracks are higher along the column height direction for middle length HSC frame columns; the length of OSC frame columns is not so long than that of HSC frame columns, and the crack distribution is dense and crack forms mesh, which show better ductility.
The virtual springs have no geometric dimension, but they can reflect the mechanical effect of bond slip.
In the rectangle cross brace hoop short column in Fig. 5(b), the crack distribution is similar compared with HC1.
With the increasing of stirrup ratios, the short column with rectangle hoop, rectangle cross brace hoop and tic tac toe stirrups appear successively few inclined cracks and more vertical cracks; With the increase of axial compression ratio, more length of horizontal cracks extended to natural axis, more vertical crack appear and appeared cracks are higher along the column height direction for middle length HSC frame columns; the crack distribution of reinforced concrete long OSC frame columns is similar with that of middle length HSC frame columns, distinguishes between them are the following: and the length of OSC frame columns is not so long than that of HSC frame columns, and the crack distribution is dense and crack forms mesh, which show better ductility.
Research on seismic behavior of high strength reinforced concrete frame columns in large-scale thermal powerplants [D].