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CONTENTS | |
Volume 23, Number 3, September 2022 |
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- Evaluating performance of the post-tensioned tapered steel beams with shape memory alloy tendons Hossein Hosseinnejad, Mohammad Ali Lotfollahi-Yaghin, Yousef Hosseinzadeh and Ahmad Maleki
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Abstract; Full Text (1804K) . | pages 221-229. | DOI: 10.12989/eas.2022.23.3.221 |
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
- Damages to Rubble Stone Masonry Structures during the January 24, 2020, Sivrice (Elazig) Earthquake in Turkey Ali Ural, Fatih K. Firat, Mehmet E. Kara, Tulin Celik and Sukran Tanriverdi
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Abstract; Full Text (2967K) . | pages 231-243. | DOI: 10.12989/eas.2022.23.3.231 |
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
- Evaluation of vibration characteristics according to changes in the fixing conditions of the electrical cabinet in power plants under an earthquake Sang-Moon Lee, Bub-Gyu Jeon and Woo-Young Jung
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Abstract; Full Text (2619K) . | pages 245-257. | DOI: 10.12989/eas.2022.23.3.245 |
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
- Assessment of tunnel damage potential by ground motion using canonical correlation analysis Changjian Chen, Ping Geng, Wenqi Gu, Zhikai Lu and Bainan Ren
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Abstract; Full Text (2411K) . | pages 259-269. | DOI: 10.12989/eas.2022.23.3.259 |
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
- Seismic behavior and design method of socket self-centering bridge pier with hybrid energy dissipation system Mengqiang Guo, Jinjie Men, Dongxin Fan and Yanli Shen
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Abstract; Full Text (2363K) . | pages 271-282. | DOI: 10.12989/eas.2022.23.3.271 |
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
- Identifying torsional eccentricity in buildings without performing detailed structural analysis G. Tamizharasi and C.V.R. Murty
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Abstract; Full Text (1781K) . | pages 283-295. | DOI: 10.12989/eas.2022.23.3.283 |
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
- Assessment of the performance of composite steel shear walls with T-shaped stiffeners Hadi Zarrintala, Ahmad Maleki and Mohammad Ali Lotfollahi Yaghin
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Abstract; Full Text (3561K) . | pages 297-313. | DOI: 10.12989/eas.2022.23.3.297 |
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
- Machine learning tool to assess the earthquake structural safety of systems designed for wind: In application of noise barriers Tabish Ali, Jehyeong Lee and Robin Eunju Kim
open access | ||
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Abstract; Full Text (2686K) . | pages 315-328. | DOI: 10.12989/eas.2022.23.3.315 |
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