Techno Press
Tp_Editing System.E (TES.E)
Login Search
You logged in as...

eas
 
CONTENTS
Volume 29, Number 3, September 2025
 

Abstract
This paper presents a novel parabolic shear deformation plate theory including the stretching effect for free vibration of the simply supported functionally graded plates embedded on the Winkler-Pasternak elastic foundation. The theory accounts for parabolic distribution of the transverse shear strains and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. This theory has only five unknowns, which is even less than the other shear and normal deformation theories. The present one has a new displacement field which introduces undetermined integral variables. Material properties are assumed to be graded in the thickness direction according to a simple power law distribution in terms of the volume power laws of the constituents. The equation of motion of the vibrated plate obtained via the classical Hamilton's principle and solved using Navier's steps. The accuracy of the proposed solution is checked by comparing the present results with those available in existing literature. The effects of the volume fraction index of functionally graded material, side-to-thickness ratio and Winkler-Pasternak elastic foundation on free vibration responses of the functionally graded plates are investigated. It can be concluded that the present theory is not only accurate but also simple in predicting the natural frequencies of functionally graded plates with stretching effect on elastic foundation.

Key Words
analytical modeling; functionally graded (FG) plates; new plate theory; shear and normal deformation; vibration; Winkler-Pasternak elastic foundation

Address
Mohammed Sid Ahmed Houari and Ali Belhocine: Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil, Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, Mascara, Algérie
Ahmed Amine Daikh: 1) Laboratoire d'Etude des Structures et de Mécanique des Matériaux, Département de Génie Civil,
Faculté des Sciences et de la Technologie, Université Mustapha Stambouli, Mascara, Algérie, 2) Artificial Intelligence Laboratory for Mechanical and Civil Structures, and Soil, University Centre of Naama, P.O. Box 66, Naama 45000, Algeria
Mohamed-Ouejdi Belarbi: Laboratoire de Recherche en Génie Civil, LRGC, Université de Biskra, B.P. 145, R.P. 07000, Biskra, Algeria
Tarek Merzouki: LISV, University of Versailles Saint-Quentin, 10-12 avenue de l

Abstract
Electricity transmission systems are crucial for contemporary societies, as they facilitate the use of overhead power lines supported by transmission towers. Due to the prevailing belief that transmission line towers are not highly susceptible to earthquakes, seismic considerations have often been overlooked in their design and analysis. This study addresses this gap by evaluating the seismic performance of Transmission Line (TL) towers. The primary goals are to identify any potential failure modes or structural weaknesses for different conditions accounting for non-uniform span, cable breakage, and cable breakage along with some bracings broken that may compromise its safety and to provide practical recommendations for improving the seismic performance of such power transmission. This study analyses finite element model of a typical TL with recorded earthquake ground movements. A four-legged square transmission line tower, seismic zone five in India at the height of 21 m, was analyzed using finite element (FE) software.

Key Words
linear time history method; power transmission tower; response spectrum method; seismic response; suspended transmission tower

Address
Rahul Kumar: Department of Civil Engineering, Birsa Institute of Technology Sindri, Jharkhand, 828123, India
Sumit Kumar: Department of Civil Engineering, Government Engineering College, Palamu, Jharkhand, 822118, India
Pranoy Debnath: Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Maharastra, 400076, India

Abstract
In order to study the seismic mechanism of masonry walls with intricate openings reinforced by polypropylene mesh-composite cement mortar, three sets of specimens with door-window openings and one set of specimens without openings were designed and manufactured. Cyclic loading tests were conducted to observe the failure phenomena during loading, which to compare and analyse the hysteretic behavior, load-bearing capacity, and stiffness degradation of each specimen. Finally, finite element numerical simulation was also performed, and the calculation results were compared with the experimental results. The results indicate that comparing the walls after single-sided surface reinforcement and double-sided surface reinforcement to unreinforced wall,the ultimate load-load-bearing capacity increases by 28.06% and 95.1%, the initial stiffness increases by 40.92% and 49.70%, and the ductility coefficient increases by 22.87% and 50.98%, respectively. During loading, the wall without openings experienced shear failure along the horizontal joint, while the wall with openings experienced shear-compression failure at the corner of the opening and between the walls of the door-window. Compared with the wall without openings, the seismic performance indicators of the wall with openings are reduced. After using the polypropylene mesh-composite cement mortar surface layer reinforcement, the development of the main cracks in the wall was inhibited, resulting in the wall experienced diagonal shear failure at the opening corner, and the initial stiffness, seismic load-load-bearing capacity, and deformation capacity were increased. The characteristic load errors of finite element analysis and experimental results for each specimen were all less than 15%. In the wall without reinforcement, the damage was most severe in the wall limbs on both sides of the opening. After reinforcement, the wall damage extended from the walls between the door-window to the corners of the opening, and the distribution of damage was consistent with the experimental failure zone.

Key Words
cyclic loading test; finite element analysis; opening masonry wall; polypropylene mesh-composite cement mortar; seismic performance

Address
Xinjie Chen, Haoran Shi, Junlong Lu, Mingdong Li and Zhenshan Wang: School of Civil Engineering And Architecture, Xi'an University of Technology, No. 5, South Jinhua Road, Xi'an, Shaanxi, China
Penggang Tian: Shaanxi Construction Engineering Holding Group Science and Technology Innovation of Future City Co,LTD., Xi'an, Shaanxi, China

Abstract
In this study, the floor acceleration response of non-isolated and isolated steel frame structures to the single rocking component of the ground motion is examined. A shaking table test was conducted, with loading applied to both non-isolated and isolated cases. The results revealed that, under the rocking component, the acceleration of non structural components (NSCs) is related to the floor position. Calculating the response of NSCs with frequencies higher than the primary structure's fundamental frequency based solely on the top floor spectra is not conservative. For NSCs with frequencies above the primary structure's fundamental frequency, it is advisable to increase damping to prevent excessive responses. Additionally, comparisons reveal that seismic isolation technology does not provide effective protection for nonstructural components at all frequencies and may even increase the response of nonstructural components with higher frequencies. Therefore, isolators with higher damping should be chosen to mitigate these effects.

Key Words
frequency; isolation; non structural components; rocking ground motions; wavelet amplitude

Address
School of Civil and Transportation Engineering, Beijing University of Civil Engineering and Architecture, Beijing,100044, China

Abstract
In this paper, extensive laboratory tests were performed to investigate the effect of different parameters such as load vibration mode, vibration frequency, foundation depth and soil relative density on the distribution of contact pressure under shallow foundations in dry sand. A test model box with dimensions (800x800x800) mm was used to perform the laboratory test. Three vibration load modes were applied to a rectangular foundation with dimensions 150x250 mm placed at surface, 75 mm depth and 150 mm depth in sand of 70% or 90% relative density. Vertical settlement and stresses under the foundation were recorded for each loading cycle through each test, five ultra-thin tactile sensors were evenly distributed along the foundation width and in contact with foundations base. It was concluded that contact pressure distribution under a foundation final shape is nearly formed after 5 to 10 minutes after the start of applying dynamic loading by increasing time (number of cycles), the contact pressure may change slightly in its values but the shape of the pressure distribution under the foundation will not be affected for nearly all test models that have been performed. An increase in contact stress under observation in the last quarter section of rectangular footing compared to the first quarter section by 25-100% when applying rocking vibration load and this increase is highly related to the increase in footing depth and lesser to the vibration frequency. This increase becomes greater at edges points to reach 50-200%.

Key Words
contact pressure; dynamic load; frequency; rectangular footing; sand

Address
Civil Engineering Department, University of Technology, Baghdad, Iraq

Abstract
Traditional prefabricated shear walls used in parking structures are typically too heavy, and the central openings for lighting significantly impair their mechanical performance. The exceptional properties of UHPC and steel enable enhanced component performance with reduced cross-sectional areas. This study employs topology optimization in ABAQUS to convert solid shear walls into truss-like configurations. Subsequent steel/UHPC trusses are designed based on the optimized topology. The optimization ensures that daylighting opening are met without compromising structural performance. The optimized truss structures were analyzed using ABAQUS, demonstrating that despite being lighter and having a higher opening ratio, the optimized trusses feature a rational arrangement of tension and compression members, resulting in improved load-bearing capacity and ductility.

Key Words
ABAQUS topology optimization module; cyclic behavior; precast parking structure; shear wall; topology optimization; UHPC and steel truss

Address
Shaoyou Chen, Jinqiao Huang, Yongqin Lu and Qinye Zhu: Ningbo Construction Engineering Group Co., Ltd, Ningbo, Zhejiang Province, China
Hao Li: 1) Ningbo Construction Engineering Group Co., Ltd, Ningbo, Zhejiang Province, China, 2) Zhejiang Key Laboratory of Intelligent Construction and Operation & Maintenance for Deep-Sea Foundations, Ningbo University of Technology, Ningbo, Zhejiang Province, China, 3) School of Architecture and Transportation Engineering, Ningbo University of Technology, Ningbo, Zhejiang Province, China

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2025 Techno-Press ALL RIGHTS RESERVED.
P.O. Box 33, Yuseong, Daejeon 34186 Korea, Email: admin@techno-press.com