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CONTENTS
Volume 23, Number 3, September 2022
 


Abstract
The external post-tension technique is one of the best strengthening methods for reinforcement and improvement of the various steel structures and substructure components such as beams. In the present work, the load carrying capacity of the post-tensioned tapered steel beams with external shape memory alloy (SMA) tendons are studied. 3D nonlinear finite element method with ABAQUS software is used to determine the effects of the increase in the flexural strength, and the improvement of the load carrying capacity. The effect of the different parameters, such as geometrical characteristics and the post-tension force applied to the tendons are also studied in this research. The results reveal that the external post-tension with SMA tendons in comparison with the steel tendons causes a significant improvement of the loading capacity. According to this, using SMA tendon for the reinforcement of the tapered beams causes a decrease in weight of these structures and as a consequence causes economic benefits for their application. This method can be used extensively for steel beams due to low executive costs and simplicity of the operation for post-tension.

Key Words
external post-tension; finite element analysis; load carrying capacity; SMA tendons; tapered steel beams

Address
Hossein Hosseinnejad and Ahmad Maleki:Department of Civil Engineering, Maragheh Branch, Islamic Azad University, Maragheh, Iran

Mohammad Ali Lotfollahi-Yaghin and Yousef Hosseinzadeh:Civil Engineering Faculty, University of Tabriz, Tabriz 51664, Iran

Abstract
The earthquake with a magnitude of Mw 6.8, which occurred on January 24, 2020, hit Sivrice (Elazig) province of Turkey. The earthquake area takes place on the East Anatolian Fault Zone (EAFZ) located between the Arabian and Turkish plates, one of the most active seismic regions in Turkey. According to the Disaster and Emergency Management Presidency of Turkey (AFAD), 584 buildings collapsed, 6845 were heavily damaged, 1207 were moderately damaged, and 14389 were slightly damaged. The authors went to the region of earthquake after the mainshock to investigate the earthquake performances of masonry buildings. This paper presents the seismological aspects of the earthquake, acceleration records, and response spectra with different damping ratios. Furthermore, some typical damages and failure mechanisms on masonry buildings like rubble stone dwellings and minarets are discussed with illustrative photos. Although many major earthquakes have occurred in the region, similar mistakes are still being made in masonry building construction. In consequence, some suggestions viewpoint of the wooden tie beams, the corner details of masonry walls, the door and window openings, the metal fasteners and the earthquake codes are made to be more careful in masonry constructions at the end of the article.

Key Words
adobe structures; masonry structures; Sivrice earthquake; strong ground motions

Address
Ali Ural, Fatih K. Firat, Mehmet E. Kara, Tulin Çelik and Sukran Tanriverdi: Aksarav University, Department of Civil Engineering, 68100, Aksarav, Turkey

Abstract
This study is a basic study on the seismic reinforcement method of anchors of fixed parts in order to reduce the effect of seismic motion that affects the facilities in the event of an earthquake. By applying the test method of ICC ES AC 156, a seismic simulation experiment was performed on the vibration table with three axes simultaneously using the number of connecting bolts between cabinets and channels as a parameter. In addition, the reliability of the experiment was verified using numerical analysis, and the part about the dynamic characteristics that could not be performed according to the experimental limit was investigated through numerical analysis. As a result of the experiment, it was confirmed that the natural frequency of the main body was increased due to the increase in the number of connecting bolts between the cabinet-channel. Accordingly, it was judged that the rigidity of the lower part of the cabinet was increased due to seismic reinforcement. It was analyzed that the impact delivered to the body was effectively reduced. In the future, if the reinforcement of the connection parts mentioned in this study is added to the existing seismic reinforcement of the electrical cabinets, it is expected that the damage to the electrical cabinets of the power plant equipment caused by an earthquake will be effectively reduced.

Key Words
connecting bolt; electrical cabinet; fixing condition; power plant; rocking response; shaking table test

Address
Sang-Moon Lee:Department of Civil Engineering, Gangneung-Wonju National University, 7 Jukheon-gil, Gangneung-si, Gangwon-Do, Republic of Korea

Bub-Gyu Jeon:Seismic Research and Test Center, Pusan National University,
49, Busandaehak-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, Republic of Korea

Woo-Young Jung:Department of Civil Engineering, Gangneung-Wonju National University, 7 Jukheon-gil, Gangneung-si, Gangwon-Do, Republic of Korea

Abstract
In this study, we introduce a canonical correlation analysis method to accurately assess the tunnel damage potential of ground motion. The proposed method can retain information relating to the initial variables. A total of 100 ground motion records are used as seismic inputs to analyze the dynamic response of three different profiles of tunnels under deep and shallow burial conditions. Nine commonly used ground motion parameters were selected to form the canonical variables of ground motion parameters (GMPCCA). Five structural dynamic response parameters were selected to form canonical variables of structural dynamic response parameters (DRPCCA). Canonical correlation analysis is used to maximize the correlation coefficients between GMPCCA and DRPCCA to obtain multivariate ground motion parameters that can be used to comprehensively assess the tunnel damage potential. The results indicate that the multivariate ground motion parameters used in this study exhibit good stability, making them suitable for evaluating the tunnel damage potential induced by ground motion. Among the nine selected ground motion parameters, peck ground acceleration (PGA), peck ground velocity (PGV), root-mean-square acceleration (RMSA), and spectral acceleration (Sa) have the highest contribution rates to GMPCCA and DRPCCA and the highest importance in assessing the tunnel damage potential. In contrast to univariate ground motion parameters, multivariate ground motion parameters exhibit a higher correlation with tunnel dynamic response parameters and enable accurate assessment of tunnel damage potential.

Key Words
canonical correlation analysis, damage potential, structural dynamic response, tunnel

Address
Changjian Chen, Ping Geng and Wenqi Gu:Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Southwest Jiaotong University,
Chengdu, Sichuan 610031, China

Zhikai Lu: CCCC Highway Consultants Co., Ltd., Beijing 100088, China

Bainan Ren:China Railway Construction Kunlun Metro Investment and Construction Management Co., Ltd., Chengdu 610040, China

Abstract
Seismic resisting self-centering bridge piers with high energy dissipation and negligible residual displacement after an earthquake event are focus topics of current structural engineering. The energy dissipation components of typical bridge piers are often relatively single; and exhibit a certain level of damage under earthquakes, leading to large residual displacements and low cumulative energy dissipation. In this paper, a novel socket self-centering bridge pier with a hybrid energy dissipation system is proposed. The seismic resilience of bridge piers can be improved through the rational design of annular grooves and rubber cushions. The seismic response was evaluated through the finite element method. The effects of rubber cushion thickness, annular groove depth, axial compression ratio, and lateral strength contribution ratio of rubber cushion on the seismic behavior of bridge piers are systematically studied. The results show that the annular groove depth has the greatest influence on the seismic performance of the bridge pier. Especially, the lateral strength contribution ratio of the rubber cushion mainly depends on the depth of the annular groove. The axial compression ratio has a significant effect on the ultimate bearing capacity. Finally, the seismic design method is proposed according to the influence of the above research parameters on the seismic performance of bridge piers, and the method is validated by an example. It is suggested that the range of lateral strength contribution ratio of rubber cushion is 0.028 ~ 0.053.

Key Words
design method; finite element; hybrid energy dissipation system; seismic performance; self-centering pier

Address
Mengqiang Guo:School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China

Jinjie Men:1)School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
2)Key Lab of Structural Engineering and Earthquake Resistance of the Ministry of Education,
Xi'an University of Architecture and Technology, Xi'an 710055, China

Dongxin Fan:School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China

Yanli Shen:School of Civil Engineering, Hebei University of Engineering, Handan 056038, China

Abstract
Seismic design codes permit the use of Equivalent Static Analysis of buildings considering torsional eccentricity e with dynamic amplification factors on structural eccentricity and some accidental eccentricity. Estimation of e in buildings is not addressed in codes. This paper presents a simple approximate method to estimate e in RC Moment Frame and RC Structural Wall buildings, which required no detailed structural analysis. The method is validated by 3D analysis (using commercial structural analysis software) of a spectrum of building. Results show that dynamic amplification factor should be applied on torsional eccentricity when performing Response Spectrum Analysis also. Also, irregular or mixed modes of oscillation arise in torsionally unsymmetrical buildings owing to poor geometric distribution of mass and stiffness in plan, which is captured by the mass participation ratio. These irregular modes can be avoided in buildings of any plan geometry by limiting the two critical parameters (normalised torsional eccentricity e/B and Natural Period Ratio τ=Tθ/T, where B is building lateral dimension, Tθ uncoupled torsional natural period and T uncoupled translational natural period). Suggestions are made for new building code provisions.

Key Words
irregular modes of oscillation; mass participation ratio; natural period ratio; torsional eccentricity

Address
G. Tamizharasi:Department of Civil Engineering, Sardar Vallabhbhai National Institute of Technology, Surat 395 007, India

C.V.R. Murty:Department of Civil Engineering, Indian Institute of Technology Madras, Chennai 600036, India

Abstract
Composite steel plate shear wall (CSPSW) is a relatively novel structural system proposed to improve the performance of steel plate shear walls by adding one or two layers of concrete walls to the infill plate. In addition, the buckling of the infill steel plate has a significant negative effect on the shear strength and energy dissipation capacity of the overall systems. Accordingly, in this study, using the finite element (FE) method, the performance and behavior of composite steel shear walls using T-shaped stiffeners to prevent buckling of the infill steel plate and increase the capacity of CSPSW systems have been investigated. In this paper, after modeling composite steel plate shear walls with and without steel plates with finite element methods and calibration the models with experimental results, effects of parameters such as several stiffeners, vertical, horizontal, diagonal, and a combination of T-shaped stiffeners located in the composite wall have been investigated on the ultimate capacity, web-plate buckling, von-Mises stress, and failure modes. The results showed that the arrangement of stiffeners has no significant effect on the capacity and performance of the CSPSW so that the use of vertical or horizontal stiffeners did not have a significant effect on the capacity and performance of the CSPSW. On the other hand, the use of diagonal hardeners has potentially affected the performance of CSPSWs, increasing the capacity of steel shear walls by up to 25%.

Key Words
composite steel plate shear wall (CSPSW); FE method; performance; T-shaped stiffener; ultimate capacity

Address
Hadi Zarrintala, Ahmad Maleki:1Department of Civil Engineering, Maragheh Branch, Islamic Azad University, Maragheh, Iran

Mohammad Ali Lotfollahi Yaghin:Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran

Abstract
Structures designed for wind have an opposite design approach to those designed for earthquakes. These structures are usually reliable if they are constructed in an area where there is almost no or less severe earthquake. However, as seismic activity is unpredictable and it can occur anytime and anywhere, the seismic safety of structures designed for wind must be assessed. Moreover, the design approaches of wind and earthquake systems are opposite where wind design considers higher stiffness but earthquake designs demand a more flexible structure. For this reason, a novel Machine learning framework is proposed that is used to assess and classify the seismic safety of the structures designed for wind load. Moreover, suitable criteria is defined for the design of wind resistance structures considering seismic behavior. Furthermore, the structural behavior as a result of dynamic interaction between superstructure and substructure during seismic events is also studied. The proposed framework achieved an accuracy of more than 90% for classification and prediction as well, when applied to new structures and unknown ground motions.

Key Words
AI, coupled analysis, ground motions, noise barriers, seismic safety, sensitivity

Address
Tabish Ali, Jehyeong Lee and Robin Eunju Kim:Department of Civil & Environmental Engineering, Hanyang University,
222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea


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