Abstract
This research investigates the seismic characteristics of steel moment frames, when parabolic shape slit shear wall is
added as infill to the frame. For this purposes, the stiffness, strength, energy dissipation and ductility capacity of the proposed
combined system, which work in parallel, are studied. The proposed system is considered as a new seismic force resisting
system. The force distribution mechanism in the slit web and boundary elements subjected to lateral force are investigated. The
design criteria and equations required for design use are developed. Results of the experiments on a steel moment frame
specimen and two frame specimens with slit shear plates, as well as finite element analysis of the specimens are used to validate
the results of analytical equations. Desirable performance of proposed system is also verified by nonlinear static and time-history
analyses of a four story structure. The results show that the proposed slit shear walls, in addition to increasing the stiffness,
strength, ductility, and energy dissipation capacity, reduce the inter-story drift ratios and also actions on the boundary elements of
moment frames, when subjected to strong ground motions, and prevent damage to other structural elements by absorbing the
plastic deformations.
Key Words
energy dissipation; mechanical characteristics; seismic performance; slit shear wall; steel moment frame
Address
Zahra Ahmadi:Faculty of Civil and Environmental Engineering, Tarbiat Modares University, Jalal Ale Ahmad Highway, Tehran, Iran
Ali Akbar Aghakouchak:Faculty of Civil and Environmental Engineering, Tarbiat Modares University, Jalal Ale Ahmad Highway, Tehran, Iran
Seyed Rasoul Mirghaderi:School of Civil Engineering, Faculty of Engineering, University of Tehran, Enghelab Square, Tehran, Iran
Abstract
This research assesses various machine learning (ML) algorithms for predicting steel frame safety during seismic
events. The study employs time-history dynamic analysis with plastic-hinge beam-column elements to form a training dataset,
consisting of W-steel section properties for input variables and the safety labels based on maximum seismic interstory drift for
output. Nine ML algorithms are tested on three different steel frames under earthquake conditions, including Naïve_Bayes,
gaussian process, k-nearest neighbors (kNN), support vector machines (SVM), deep learning (DL), random forest (RF), gradient
tree boosting (GTB), extreme gradient boosting (XGBoost), and light gradient boosting machines (LightGBM). Findings
indicate that in view of accuracy, Naïve_Bayes, SVM, and kNN perform weaker compared to tree-based methods like RF, GTB,
XGBoost, and LightGBM, with XGBoost and LightGBM outperforming. Regarding training time, Naïve_Bayes and kNN show
the shortest times, whereas Gaussian, GTB, and DL experience substantial increases as the training dataset grows. RF and
XGBoost have moderate times, but LightGBM is notably efficient. Overall, LightGBM demonstrates superior performance,
followed by XGBoost and RF in predicting steel frame safety during seismic events.
Address
Viet-Hung Truong:1)Faculty of Civil Engineering, Thuyloi University, 175 Tay Son, Dong Da, Hanoi 100000, Vietnam
2)Center of Excellence in Applied Mechanics and Structures, Department of Civil Engineering, Faculty of Engineering,
Chulalongkorn University, Bangkok 10330, Thailand
Sawekchai Tangaramvong:Center of Excellence in Applied Mechanics and Structures, Department of Civil Engineering, Faculty of Engineering,
Chulalongkorn University, Bangkok 10330, Thailand
Manh-Cuong Nguyen:Faculty of Civil Engineering, Thuyloi University, 175 Tay Son, Dong Da, Hanoi 100000, Vietnam
Hoang-Anh Pham:1)Department of Structural Mechanics, Hanoi University of Civil Engineering, 55 Giai Phong Road, Hanoi 100000, Vietnam
2)Frontier Research Group of Mechanics of Advanced Materials and Structures (MAMS), Hanoi University of Civil Engineering,
55 Giai Phong Road, Hanoi 100000, Vietnam
Abstract
This study aims to investigate the bond-slip behaviour between shaped steel and polyvinyl alcohol (PVA) fibrereinforced concrete, a critical aspect affecting the structural performance of steel-concrete composite structures. The experiment
on 14 specimens, considering various parameters such as concrete strength, cover thickness, anchorage length, PVA fibre
volume, and the presence of shear studs were conducted. A novel experimental method was devised to analyse the bond-slip
characteristics between shaped steel and PVA fibre concrete. All specimens exhibited failure due to the bond between shaped
steel and concrete. The load-slip curve exhibited four distinct stages: the initial stage, slip stage, descending stage, and horizontal
residual stage. Notably, the addition of PVA fibre significantly enhanced the load-bearing capacity, with optimal performance
observed at a fibre volume of 8 kg/m3, surpassing conventional concrete bond strength. Moreover, increasing PVA concrete
strength, anchorage length, and the use of shear studs were found to augment the bond strength. To further understand this bondslip behaviour, a constitutive model correlating bond strength with characteristic slip values was developed, and it aligns well
with experimental results, validating its accuracy and applicability.
Key Words
bond-slip constitutive model; bond strength; push-out test; PVA fiber concrete; shape steel
Address
Qinglin Tao:Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
Xuyun Chen:Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
Weiping Pei:Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
Xi Jia:Dept. of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, China
Rencai Jin:Technology Center, China MCC17 Group Co, LTD, Ma'anshan 243000, China
Haikun Zhang:Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
Zhengyi Kong:1)Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
2)Institute for Sustainable Built Environment, Heriot-Watt University, United Kingdom
George Vasdravellis:Institute for Sustainable Built Environment, Heriot-Watt University, United Kingdom
Song Jin:Dept. of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243032, China
Abstract
In this experimental study, cyclic loading tests were conducted to evaluate the seismic performance of concretefilled hollow precast concrete (PC) columns (HPCC) manufactured using an inner mold composed of shear studs and louver
plates. Both shear studs and louver plates were employed to ensure the structural integrity between the old concrete (outer shell)
and new concrete (cast-in-place concrete). The hollow ratio of the test specimens fabricated using the inner mold was 22%. Up
to a drift ratio of 3.0%, the hysteresis loops, yielding stiffnesses, and dissipated energies of the hollow column specimens were
nearly identical to those of the monolithic columns. Beyond the peak strength, the hollow specimens—monolithically connected
to the foundation—exhibited a lower hysteresis loop, dissipated energy, and displacement ductility ratio than the monolithic
column specimens; this trend was more pronounced in the PC specimens with sleeve connections. The strain histories of the
longitudinal bars of all the specimens were nearly identical, regardless of the presence of a hollow section. All the column
specimens exhibited a measured peak moment exceeding the nominal peak moment in accordance with the ACI 318 standard.
Overall, the HPCC specimens fabricated using the proposed prefabricated inner mold exhibited structural behavior similar to
that of conventional RC columns.
Key Words
hollow PC column; precast concrete column; reinforced concrete column; seismic performance; steel stud
Address
Chae-Rim Im:Department of Architectural Engineering, Kyonggi University, Graduate School, Suwon, Republic of Korea
Sanghee Kim:Department of Architectural Engineering, Kyonggi University, Suwon, Republic of Korea
Ju-Hyun Mun:Department of Architectural Engineering, Kyonggi University, Suwon, Republic of Korea
Keun-Hyeok Yang:Department of Architectural Engineering, Kyonggi University, Suwon, Republic of Korea
Jae-Il Sim:Korea Disaster Prevention Safety Technology Co. Ltd, Gwangju, Republic of Korea
Abstract
In this paper, the static mechanical properties of lithium slag concrete filled steel tube (LSCFST) short columns
strengthened by CFRP strips are investigated, including experimental study and theoretical analysis. Through the experimental
phenomena and data analysis of 17 columns with different parameters, it can be concluded that CFRP strips can effectively
delay the buckling of square steel tubes; Contrary to increasing the spacing of CFRP strips, increasing the lithium slag
replacement rate and the number of CFRP strips can improve the bearing capacity and ductility of the specimen; The existing
methods for calculating the ultimate strength of CFRP strengthened LSCFST columns are compared and suggestions are given;
The finite element model of CFRP strengthened square LSCFST short column is established and verified.
Key Words
axial compression capacity; axial pressure; CFRP; lithium slag; short column
Address
Jiongfeng Liang:Faculty of Civil & Architecture Engineering, East China University of Technology, Nanchang, China
Liuhaoxiang Wang:Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, China
Wanjie Zou:College of Civil and Architecture Engineering, Guangxi University of Science and Technology, Liuzhou, China
Wei Li:College of Civil and Architecture Engineering, Wenzhou University, Wenzhou, China
Abstract
A longitudinal push-out test of the prototype full-size rail-WJ-8B fastener system was carried out, and eight various
torque of bolts were considered. Through the whole process analysis of rail push-out test, key indicators such as nominal yield
force, nominal yield displacement, peak resistance and stiffness of rail-fastener system were obtained, the results show that in the
push-out process, no obvious damages were occur to each component of the fastener system, and the worst damage was only
manifested in the surface scratches of the insulated gauge block; the resistance-displacement of the rail-fastener system
presented three obvious stages, namely, the elastic stage, the nominal damage stage, and the nominal failure stage. Under
different torques, the nominal yield displacement was basically kept around 1.5 mm to 2.5 mm. When the torque of fastener was
110N m (small resistance), the nominal yield force was 4.20kN and the peak resistance was 5.05kN; when the torque was
160N m (the constant resistance), the nominal yield force was 5.52kN and the peak resistance was 7.48kN, and the nominal
yield force increased by 1.32kN, an increase of 31%, and peak resistance increased by 2.43kN, an increase of about 48%. When
the longitudinal displacement of the rail reached to 20mm, the longitudinal resistance of the fastener system under different
cases decreased with the increase of the displacement of the rail, and the rail-fastener system was considered to enter the
nominal failure stage. Finally, the resistance- displacement mechanical model of WJ-8B fastener system was deduced.
Address
Xiang Liu:1)School of Civil Engineering, Fujian University of Technology, Fuzhou 350118, China
2)Power China Chizhou Changzhi Prefabricated Construction Co., LTD., Chizhou 247100, China
Tianqi He:School of Civil Engineering, Fujian University of Technology, Fuzhou 350118, China
Lizhong Jiang:1)National Engineering Research Center for High-speed Railway Construction Technology, Changsha 410075, China
2)School of Civil Engineering, Central South University, Changsha 410075, China
Zhipeng Lai:1)National Engineering Research Center for High-speed Railway Construction Technology, Changsha 410075, China
2)School of Civil Engineering, Central South University, Changsha 410075, China
Lin Pang:China Railway Eryuan Engineering Group Co.,LTD. Chengdu 610031, China
Xiangqian Bao:Highway Vehicle Toll Collection Service Center of Xilingol League, Xilingol League 026000, China
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