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Abstract
A three-dimensional structural health monitoring (SHM) system based on multiscale entropy (MSE) and multiscale cross-sample entropy (MSCE) is proposed in this paper. The damage condition of a structure is rapidly screened through MSE analysis by measuring the ambient vibration signal on the roof of the structure. Subsequently, the vertical damage location is evaluated by analyzing individual signals on different floors through vertical MSCE analysis. The results are quantified using the vertical damage index (DI). Planar MSCE analysis is applied to detect the damage orientation of damaged floors by analyzing the biaxial signals in four directions on each damaged floor. The results are physically quantified using the planar DI. With progressive vertical and planar analysis methods, the damaged floors and damage locations can be accurately and efficiently diagnosed. To demonstrate the performance of the proposed system, performance evaluation was conducted on a three-dimensional seven-story steel structure. According to the results, the damage condition and elevation were reliably detected. Moreover, the damage location was efficiently quantified by the DI. Average accuracy rates of 93% (vertical) and 91% (planar) were achieved through the proposed DI method. A reference measurement of the current stage can initially launch the SHM system; therefore, structural damage can be reliably detected after major earthquakes.

Key Words
three-dimensional; structural health monitoring; vertical; planar; cross-sample entropy; multiscale

Address
Tzu Kang Lin, Tzu Chi Tseng and Ana G. Laínez: Department of Civil Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan 300, ROC

Abstract
Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Beams of the model steel structure are then retrofitted by using CFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of FRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of CFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 34.43% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

Key Words
experimental modal analysis; CFRP; modal parameter; EFDD; shake table

Address
Azer A. Kas

Abstract
This study evaluates the effectiveness of a newly developed retrofitting scheme for masonry-infilled non-ductile RC frames experimentally and by numerical simulation. The technique focuses on modifying the load path and yield mechanism of the infilled frame to enhance the ductility. A vertical gap between the column and the infill panel was strategically introduced so that no shear force is directly transferred to the column. Steel brackets and small vertical steel members were then provided to transfer the interactive forces between the RC frame and the masonry panel. Wire meshes and high-strength mortar were provided in areas with high stress concentration and in the panel to further reduce damage. Cyclic load tests on a large-scale specimen of a single-bay, single-story, masonry-infilled RC frame were carried out. Based on those tests, the retrofitting scheme provided significant improvement, especially in terms of ductility enhancement. All retrofitted specimens clearly exhibited much better performances than those stipulated in building standards for masonry-infilled structures. A macro-scale computer model based on a diagonal-strut concept was also developed for predicting the global behavior of the retrofitted masonry-infilled frames. This proposed model was effectively used to evaluate the global responses of the test specimens with acceptable accuracy, especially in terms of strength, stiffness and damage condition.

Key Words
non-ductile frame; masonry infill; seismic retrofitting; cyclic test; macro model

Address
Jarun Srechai, Arnon Wongkaew: Department of Civil Engineering, Burapha University, 169 Saen-Sook, Chonburi, 20131, Thailand Sutat Leelataviwat: Department of Civil Engineering, King Mongkut\'s University of Technology Thonburi,126 Thung Khru, Bangkok, 10140, Thailand Panitan Lukkunaprasit: Department of Civil Engineering, Chulalongkorn University, 254 Phatumwan, Bangkok, 10330, Thailand

Abstract
Steel plate shear walls (SPSWs) are effective lateral systems which have high initial stiffness, appropriate ductility and energy dissipation capability. Recently, steel plate shear walls with low yield point strength (LYP), were introduced and they attracted the attention of designers. Structures with this new system, besides using less steel, are more stable. In the present study, the effects of plates with low yield strength on the seismic design parameters of steel frames with steel plate shear walls are investigated. For this purpose, a variety of this kind of structures with different heights including the 2, 5, 10, 14 and 18-story buildings are designed based on the AISC seismic provisions. The structures are modeled using ANSYS finite element software and subjected to monotonic lateral loading. Parameters such as ductility (µ), ductility reduction (Rµ), over-strength (

Key Words
steel plate shear wall; low yield strength; ductility factor; over-strength factor; response modification factor; displacement amplification factor

Address
Negin Soltani, Karim Abedi, Mehdi Poursha: Faculty of Civil Engineering, Sahand University of Technology, Tabriz, Iran Hassan Golabi: Department of Structural Engineering, Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran

Abstract
This article is all about using the MR damper with an external lever system for mitigation torsional and transitional lateral displacements by using of PID control algorithm. The torsional modes are so destructive and can be varied during an earthquake therefore, using a semi-active control system mostly recommended for them. In this paper the corner lateral displacement of each floor obtains and then it equivalents in a solid member and it connects to an MR damper, which relies to a rigid structure to reduce the response. An MR damper is a semi-active control system, which can absorb a lot of energy by injecting current to it. This amount of current is very low and needs low power supply, but it increases the amount of damper force, rather than inactive systems like viscous dampers. This paper will show the appropriate algorithm for current injection into MR damper when the eccentricity of the load is changed by using of Bouc-Wen and Bingham´s methods and illustrates the coincidence of them.

Key Words
MR damper; semi-active control system; torsion; Bingham model; Bouc-Wen model

Address
Kambiz Takin: Department of Civil Engineering, Safadasht Branch, Islamic Azad University, Tehran, Iran Behrokh Hosseini Hashemi: Structural Engineering Research Center (SERC), International Institute of Earthquake Engineering & Seismology(IIEES), Tehran, Iran, Member of IEEA Masoud Nekooei: Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

Abstract
In this paper, the influence of the rotational component, about a vertical axis, of earthquake ground motion on the response of building structures subjected to seismic action is considered. The torsional component of ground motion is generated from the records of translational components. Torsional component of ground motion is then, together with translational components, applied in numerical linear dynamic analysis of different reinforced concrete framed structure of three stories buildings. In total, more than 40 numerical models were created and analyzed. The obtained results show clearly the dependence of the effects of the torsional seismic component on structural system and soil properties. Thus, the current approach in seismic codes of accounting for the effects of accidental torsion due to the torsional ground motion, by shifting the center of mass, should be reevaluated.

Key Words
torsional rigidity; translational rigidity; accidental eccentricity; seismic torsional component; torsional coupling

Address
Abderrahmane Ouazir, Asma Hadjadj and Abdelkader Benanane: epartment of Civil Engineering and Architecture, Abdel Hamid Ibn Badis University, Faculty for Sciences and Technology, Av. Hamadou Hossine, Mostaganem 27000, Algeria

Abstract
In this study, the characteristics of site amplification at seismic observation stations in Japan were estimated using the attenuation relationship of each station´s response spectrum. Ground motion records observed after 32 earthquakes were employed to construct the attenuation relationship. The station correction factor at each KiK-net station was compared to the transfer functions between the base rock and the surface. For each station, the plot of the station correction factor versus the period was similar in shape to the graphs of the transfer function (amplitude ratio versus period). Therefore, the station correction factors are effective for evaluating site amplifications considering the period of ground shaking. In addition, the station correction factors were evaluated with respect to the average shear wave velocities using a geographic information system (GIS) dataset. Lastly, the site amplifications for specific periods were estimated throughout Japan.

Key Words
attenuation relationship; station correction factor; average shear wave velocity; site amplification

Address
Yoshihisa Maruyama: Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan Masaki Sakemoto: Nippon Koei Co., Ltd., 1-14-6 Kudankita, Chiyoda-ku, Tokyo 102-8539, Japan

Abstract
Stone masonry is one of the oldest construction types due to the natural and free availability of stones and the relatively easy construction. Since stone masonry is brittle, it is also very vulnerable and in the case of earthquakes damage, collapses and causalities are very likely to occur, as it has been seen during the last Italian earthquake in Amatrice in 2016. In the recent years, some researchers have performed experimental tests to improve the knowledge of the behaviour of stone masonry. Concurrently, there is the need to reproduce the seismic behaviour of these structures by numerical approaches, also in consideration of the high cost of experimental tests. In this work, an alternative simplified procedure to numerically reproduce the diagonal compression and shear compression tests on a rubble stone masonry is proposed within the finite element method. The proposed procedure represents the stone units as rigid bodies and the mortar as a plastic material with compression and tension inelastic behaviour calibrated based on parametric studies. The validation of the proposed model was verified by comparison with experimental data. The advantage of this simplified methodology is the use of a limited number of degrees of freedom which allows the reduction of the computational time, which leaves the possibility to carry out parametric studies that consider different wall configurations.

Key Words
stone masonry; numerical modelling; finite element; experimental tests

Address
Nicola Tarque: Division of Civil Engineering, Pontificia Universidad Catolica del Peru, Av. Universitaria 1801, Lima, Peru Guido Camata, Enrico Spacone: Department of Engineering and Geology, University G. D´Annunzio, Viale Pindaro 42, Pescara, Italy Andrea Benedetti: Department of Civil, Chemical, Environmental, and Materials Engineering, University of Bologna, Via Zamboni 33, Bologna, Italy

Abstract
Displacement response and corresponding maximum response energy of structures are key parameters to assess the dynamic effect or even more destructive structural damage of the structures. By employing them, this research has compared the structural responses of jacket supported offshore wind turbine (OWT) subjected to seismic excitations apprehending earthquake incidence, when (a) soil-structure interaction (SSI) has been ignored and (b) SSI has been considered. The effect of earthquakes under arbitrary angle of excitation on the OWT has been investigated by means of the energy based wavelet transformation method. Displacement based fragility analysis is then utilized to convey the probability of exceedance of the OWT at different soil site conditions. The results show that the uncertainty arises due to multi-component seismic excitations along with the diminution trend of shear wave velocity of soil and it tends to reduce the efficiency of the OWT to stand against the ground motions.

Key Words
offshore wind turbine; soil-structure interaction; incident angle; wavelet transformation; fragility curve

Address
Faria Sharmin, Mosaruf Hussan, Dookie Kim: Department of Civil Engineering, Kunsan National University, 558 Daehak-ro, Kunsan, Jeonbuk 54150, Republic of Korea Sung Gook Cho: Innose Tech Company Limited, Republic of Korea

Abstract
Passive dynamic vibration absorbers (DVAs) are often used to suppress the excessive vibration of a large structure due to their simple construction and low maintenance cost compared to other vibration control techniques. A new type of passive DVA consists of two pendulums connected with spring and dashpot element is investigated. This research evaluated the performance of the DVA in reducing the vibration response of a two degree of freedom shear structure. A model for the two DOF vibration system with the absorber is developed. The nominal absorber parameters are calculated using a Genetic Algorithm(GA) procedure. A parametric study is performed to evaluate the effect of each absorber parameter on performance. The simulation results show that the optimum condition for the absorber frequencies and damping ratios is mainly affected by pendulum length, mass, and the damping coefficient of the pendulum´s hinge joint. An experimental model validates the theoretical results. The simulation and experimental results show that the proposed technique is able be used as an effective alternative solution for reducing the vibration response of a multi degree of freedom vibration system.

Key Words
vibration; structure; damping; building; earthquake

Address
Mulyadi Bur, Lovely Son, Meifal Rusli: Department of Mechanical Engineering, Faculty of Engineering, Andalas University, Kampus Limau Manis 25163, Indonesia Masaaki Okuma: Department of Mechanical and Aerospace Engineering, Tokyo Institute of Technology, 2-12-1-I3-15 Ookayama, Meguro-ku, Tokyo 152-8552, Japan

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