Discussion of “A Clarification of Orthogonal Effects in a Three-Dimensional Seismic Analysis” by E. L. Wilson, I. Suharwardy, and A. Habibullah

1996 ◽  
Vol 12 (2) ◽  
pp. 357-361 ◽  
Author(s):  
Oscar A. López ◽  
Ronald Torres
2019 ◽  
Vol 3 (Special Issue on First SACEE'19) ◽  
pp. 207-2016
Author(s):  
Guillermo Martinez ◽  
David Castillo ◽  
José Jara ◽  
Bertha Olmos

This paper presents a first approximation of the seismic vulnerability of a sixteenth century building which is part of the historical center of Morelia, Mexico. The city was declared World Heritage by United Nations Educational, Scientific and Cultural Organization in 1991. The modeling and analysis of the building was carried out using a three-dimensional elastic tetrahedral finite elements model which was subjected to probabilistic seismic demands with recurrences of 500 yrs and 1000 yrs in addition to real seismic records. The model was able to correctly identify cracking pattern in different parts of the temple due to gravitational forces. High seismic vulnerability of the arched window and the walls of the middle part of the bell tower of the temple was indicated by the seismic analysis of the model.


2021 ◽  
Vol 7 ◽  
Author(s):  
Vasiliki Terzi ◽  
Asimina Athanatopoulou

The present study aims to investigate the effects of the seismic vertical component on the pathology of Xana monument which is a typical caravanserai, constructed circa 1375–1385 and is located in the archeological site of the municipality of Trainapoulis, Greece. The monument’s plan is rectangular and the three-leaf masonry circumferential walls support a hemicylindrical dome constructed by bricks and mortar. The structure consisted of two consecutive parts: one for the travelers and one for the animals. Nowadays, the triangular roof, that covered the structure, and the first part of the monument do not exist. Xana suffers tensile cracks along the interior surface of the dome, a vertical fracture located on the northern wall and vertical tensile cracks located at the openings. A three-dimensional finite element model of the initial state of Xana is constructed. Non-linear material behavior is taken into account as well as soil-structure interaction effects. An adequate number of near-field earthquake events has been used, taking into account that they are related to significant vertical components. The structural seismic analysis is conducted for two cases. The first case refers to the action of the two horizontal-component of ground motions while the second one takes into account the three translational seismic components. The pathology estimation reveals important information concerning the structural effects due to vertical accelerations.


2021 ◽  
Vol 25 (1) ◽  
pp. 88-98
Author(s):  
Mokhtar Messaad ◽  
Messoud Bourezane ◽  
Mohamed Latrache ◽  
Amina Tahar Berrabah ◽  
Djamel Ouzendja

Abstract Concrete dams are considered as complex construction systems that play a major role in the context of both economic and strategic utilities. Taking into account reservoir and foundation presence in modeling the dam-reservoir-foundation interaction phenomenon leads to a more realistic evaluation of the total system behavior. The article discusses the dynamic behavior of dam-reservoir-foundation system under seismic loading using Ansys finite element code. Oued Fodda concrete dam, situated at Chlef, in North-West of Algeria, was chosen as a case study. Parametric study was also performed for different ratios between foundation Young's modulus and dam Young's modulus E f /E d (which varies from 0.5 to 4). Added mass approach was used to model the fluid reservoir. The obtained results indicate that when dam Young's modulus and foundation Young's modulus are equal, the foundation soil leads to less displacements in the dam body and decreases the principal stresses as well as shear stresses.


2014 ◽  
Vol 2014 ◽  
pp. 1-10
Author(s):  
Li Tian ◽  
Wenming Wang ◽  
Hui Qian

The effect analysis of strain rate on power transmission tower-line system under seismic excitation is studied in this paper. A three-dimensional finite element model of a transmission tower-line system is created based on a real project. Using theoretical analysis and numerical simulation, incremental dynamic analysis of the power transmission tower-line system is conducted to investigate the effect of strain rate on the nonlinear responses of the transmission tower and line. The results show that the effect of strain rate on the transmission tower generally decreases the maximum top displacements, but it would increase the maximum base shear forces, and thus it is necessary to consider the effect of strain rate on the seismic analysis of the transmission tower. The effect of strain rate could be ignored for the seismic analysis of the conductors and ground lines, but the responses of the ground lines considering strain rate effect are larger than those of the conductors. The results could provide a reference for the seismic design of the transmission tower-line system.


Author(s):  
Naibin Jiang ◽  
Feng-gang Zang ◽  
Li-min Zhang ◽  
Chuan-yong Zhang

The seismic analysis on reactor structure was performed with a new generation of finite element software. The amount of freedom degree of the model was more than twenty millions. The typical responses to operational basis earthquake excitation were given. They are larger than those with two-dimensional simplified finite element method, and the reasons of this phenomenon were analyzed. The feasibility of seismic analysis on large-scale three-dimensional finite element model under existing hardware condition was demonstrated, so some technological reserves for dynamic analysis on complicated equipments or systems in nuclear engineering are provided.


2020 ◽  
Vol 47 (12) ◽  
pp. 1372-1386 ◽  
Author(s):  
Amin Asgarian ◽  
Ghyslaine McClure

In most current building codes, seismic design of non-structural components (NSCs) is addressed through empirical equations that do not capture NSC response amplification due to tuning effects with higher and torsional modes of buildings and that neglect NSC damping. This work addresses these shortcomings and proposes a practical approach to generate acceleration NSC floor design spectra (FDS) in buildings directly from their corresponding uniform hazard spectra (UHS). The study is based on the linear seismic analysis of 27 reinforced concrete buildings located in Montréal, Canada, for which ambient vibration measurements (AVM) are used to determine their in situ three-dimensional dynamic characteristics. Pseudo acceleration floor response spectra (PA-FRS) are derived at every building floor for four different NSCs damping ratios. The calculated roof FRS are compared with the 5% damped UHS and a formulation is proposed to generate roof FDS for NSCs with 5% damping directly from the UHS.


2014 ◽  
Vol 14 (03) ◽  
pp. 1350074 ◽  
Author(s):  
L. J. Leu ◽  
J. T. Chang

A new simple approach is proposed to search for the optimal placement of dampers in nonsymmetrical three-dimensional (3D) structures. Dampers are placed uniformly and initially at each storey of two selected bays of the bare structures and the time-history seismic analysis is performed. The maximal inter-storey drift ratio is chosen as the performance index. Then the inter-storey drift ratio is checked for the locations where dampers were added. The damper in the location with the minimal inter-storey drift ratio is moved to the location having the maximal inter-storey drift ratio. This process is repeated until the prescribed stop criterion is met. Both linear and nonlinear viscous dampers are used in this study. The damping coefficient of added dampers for the initial damper placement is determined by setting the maximal inter-storey drift ratio of the whole structure equal to a certain value when a ground motion is applied. In the proposed relocation process, the maximal inter-storey drift ratio will be reduced significantly. Three examples, including two 10-storey and one 20-storey 3D nonsymmetrical structures, are used to demonstrate the efficiency and accuracy of the proposed approach. The results are compared with those obtained using the simplified sequential search algorithm (SSSA). It is found that the proposed approach requires fewer number of time-history analysis than that using the SSSA while their accuracy is comparable.


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