scholarly journals Inelastic Parametric Analysis of Seismic Responses of Multistorey Bidirectional Eccentric Structure

2018 ◽  
Vol 2018 ◽  
pp. 1-20
Author(s):  
Yu-ping Kuang ◽  
Xin-liang Jiang ◽  
Nan Jiang
Keyword(s):  
Seismic Response ◽  
Parametric Analysis ◽  
Coupling Effect ◽  
Parameter Analysis ◽  
Seismic Responses ◽  
Load Direction ◽  
General Law ◽  
Eccentric Structure ◽  
Natural Frequency Variation ◽  
Elastic Stage

This paper conducts a parametric study on the seismic response of multistorey bidirectional eccentric structures from elastic stage to inelastic stage. Based on a simplified multistorey bidirectional eccentric model composed of bidirectional lateral load-resisting members, a general law is proposed for three-stage natural frequency variation behaviour from elastic stage to inelastic stage of eccentric frame structures with different layers. Different simplification treatments are conducted on each stage and the three stable parameter analysis stages are defined. The corresponding dynamic stiffness matrices and motion equations in different loading stages are derived. On this basis, a parametric analysis of seismic response of a three-storey bidirectional regular eccentric structure from elastic stage to inelastic stage is conducted. Effects of the uncoupled torsion to lateral frequency ratios (Ω) and bidirectional eccentricities on the seismic responses are investigated. The results reveal that as Ω increases, translational displacement in the load direction first decreases and then increases; meanwhile, the displacement perpendicular to load direction and torsion displacement first rise and then decrease sharply. When Ω=1.1, the coupling effect between the translation in the load direction and the torsion is at its strongest condition. Increasing the eccentricities leads to a decrease in the displacement in the load direction as well as an increase in the displacement perpendicular to load direction and torsion displacement. Variation regularity of inelastic seismic response is remarkably different from that in elastic stage. The lateral-torsional coupling effect of the bidirectional eccentric structure is closely related to both the period ratio and the bidirectional eccentricities.

Parametric analysis of the seismic response of a 2D sedimentary valley: implications for code implementations of complex site effects

2005 ◽  
Vol 25 (4) ◽  
pp. 303-315 ◽  
Author(s):  
Konstantia Makra ◽  
Francisco J. Chávez-García ◽  
Dimitrios Raptakis ◽  
Kyriazis Pitilakis
Keyword(s):  
Seismic Response ◽  
Parametric Analysis ◽  
Site Effects

Effect of Structure-Soil-Structure Interaction (SSSI) between Three Dissimilar Adjacent Bridges

2021 ◽  
Author(s):  
Mohanad Talal Alfach ◽  
Ashraf Ayoub
Keyword(s):  
Seismic Response ◽  
Seismic Behavior ◽  
Soil Structure ◽  
Soil Structure Interaction ◽  
Numerical Analyses ◽  
Seismic Responses ◽  
Structure Interaction ◽  
Internal Forces ◽  
Isolated Bridge ◽  
Effect Of Structure

Abstract The present study assesses the effect of Structure-Soil-Structure-Interaction (SSSI) on the seismic behavior of three dissimilar adjacent bridges by comparing their seismic responses with the seismic response of the isolated bridge including Soil-Structure-Interaction (SSI). To this end, an extensive series of numerical analyses have been carried out to elicit the effects of Structure-Soil-Structure-Interaction (SSSI) on the seismic behavior of three dissimilar bridges with different superstructure masses. The studied bridges are based on groups of piles founded in nonlinear clay. A parametric study has been performed for configurations of three dissimilar bridges with superstructure masses ratios of 200% and 300%, concentrating on the influence of the inter-bridge spacing, and the geometrical position of the bridges towards each other and towards the seismic excitation direction. The numerical analyses have been conducted using a three-dimensional finite difference modeling software FLAC 3D (Fast Lagrangian analysis of continua in 3 dimensions). The results of the numerical simulations clearly show that the seismic responses of the dissimilar grouped bridges were strongly influenced by the neighboring bridges. In particular, the results reveal a salient positive impact on the acceleration of the superstructure by a considerable drop (up to 90.63%) and by (up to 91.27%) for the internal forces induced in the piles. Comparably, the influence of bridge arrangement towards the seismic loading were prominent on both of superstructure acceleration and the internal forces in the piles. The responses were as much as 27 times lesser for the acceleration and 11 times smaller for the internal forces than the response of the isolated bridge. Contrarily, the inter-bridge spacing has a limited effect on the seismic response of the grouped bridges.

A Weibull Stress Approach Incorporating the Coupling Effect of Constraint and Plastic Strain in Cleavage Fracture Toughness Predictions

2014 ◽  
Author(s):  
Claudio Ruggieri ◽  
Robert H. Dodds
Keyword(s):  
Fracture Toughness ◽  
Plastic Strain ◽  
Cleavage Fracture ◽  
Coupling Effect ◽  
Crack Size ◽  
Parameter Analysis ◽  
Pressure Vessel Steel ◽  
Fracture Parameter ◽  
Vessel Steel ◽  
Weibull Stress

This work describes a micromechanics methodology based upon a local failure criterion incorporating the strong effects of plastic strain on cleavage fracture coupled with statistics of microcracks. A central objective is to gain some understanding on the role of plastic strain on cleavage fracture by means of a probabilistic fracture parameter and how it contributes to the cleavage failure probability. A parameter analysis is conducted to assess the general effects of plastic strain on fracture toughness correlations for conventional SE(B) specimens with varying crack size over specimen width ratios. Another objetive is to evaluate the effectiveness of the modified Weibull stress (σ̃w) model to correct effects of constraint loss in PCVN specimens which serve to determine the indexing temperature, T0, based on the Master Curve methodology. Fracture toughness testing conducted on an A285 Grade C pressure vessel steel provides the cleavage fracture resistance (Jc) data needed to estimate T0. Very detailed non-linear finite element analyses for 3-D models of plane-sided SE(B) and PCVN specimens provide the evolution of near-tip stress field with increased macroscopic load (in terms of the J-integral) to define the relationship between σ̃w and J. For the tested material, the Weibull stress methodology yields estimates for the reference temperature, T0, from small fracture specimens which are in good agreement with the corresponding estimates derived from testing of much larger crack configurations.

scholarly journals On Predicting the Seismic Response of Acceleration-Sensitive Non-Structural Components in Buildings

2018 ◽  
Author(s):  
Carmine Lima ◽  
Enzo Martinelli
Keyword(s):  
Dynamic Response ◽  
Seismic Response ◽  
Parametric Analysis ◽  
Short Review ◽  
Structural Components ◽  
Main Structure ◽  
Current State ◽  
Critical Issues ◽  
Key Features ◽  
Two Degree Of Freedom

This paper is intended at highlighting the main mechanical parameters controlling the behavior of the so-called "acceleration-sensitive" Non-Structural Components (NSCs). In the first part a short review of the current state of knowledge and the critical issues related to the prediction of the seismic response of NSCs is reported. Then, the paper presents the results of a numerical parametric analysis intended to capture the key features of the dynamic response of a two-degree-of-freedom (2DOF) system which is supposed to be representative of both the main structure and the "non-structural" component (NSC). Particularly, it allows to simulate the coupled behaviour of both main structure and NSC and evaluating their response. The main parameters controlling the dynamic response of NSCs emerge from this study, which could pave the way towards formulating more mechanically consistent relationships for evaluating the maximum accelerations induced by seismic shakings on NSCs.

Elasto-Plastic Analysis of Seismic Response of Valve-Hall Structure with Suspension Valves of Large-Scale Converter Station

2011 ◽  
Vol 94-96 ◽  
pp. 1941-1945
Author(s):  
Yi Wu ◽  
Chun Yang ◽  
Jian Cai ◽  
Jian Ming Pan
Keyword(s):  
Seismic Response ◽  
Large Scale ◽  
Seismic Waves ◽  
Tensile Force ◽  
Response Analysis ◽  
Vertical Acceleration ◽  
Seismic Responses ◽  
Seismic Response Analysis ◽  
Finite Element Software ◽  
Plastic Analysis

Elasto-plastic analysis of seismic responses of valve hall structures were carried out by using finite element software, and the effect of seismic waves on the seismic responses of the valve hall structures and suspension equipments were studied. Results show that significant torsional responses of the structure can be found under longitudinal and 3D earthquake actions. Under 3D earthquake actions, the seismic responses of the suspension valves are much more significant than those under 1D earthquake actions, the maximum tensile force of the suspenders is about twice of that under 1D action. The seismic responses of the suspension valves under vertical earthquake actions are much stronger than those under horizontal earthquake actions, when suffering strong earthquake actions; the maximum vertical acceleration of the suspension valves is about 4 times of that under horizontal earthquake actions. It is recommended that the effects of 3D earthquake actions on the structure should be considered in seismic response analysis of the valve hall structure.

scholarly journals Seismic Response of Prestressed Anchors with Frame Structure

2020 ◽  
Vol 2020 ◽  
pp. 1-15 ◽  
Author(s):  
Shuaihua Ye ◽  
Zhuangfu Zhao
Keyword(s):  
Seismic Response ◽  
Shaking Table Test ◽  
Coupling Effect ◽  
Soil Mass ◽  
Calculation Model ◽  
Shaking Table ◽  
Frame Structure ◽  
Dynamic Calculation ◽  
Concentrated Mass ◽  
Linear Spring

Based on the equivalent mass-spring model and considering the coupling effect between creep soil and prestressed anchors, the dynamic calculation model of prestressed anchors with frame structure is established. The soil mass is expressed in the form of concentrated mass. The action of the frame structure on the soil is treated as a parallel coupling of a linear spring and a linear damper, and the free section of the anchor is treated as a linear spring. Considering the creep characteristics, the soil is regarded as a Generalized Kelvin body and the anchoring section of the anchor is regarded as an equivalent spring body, which are coupled in parallel. Considering the effect of slope height, the dynamic calculation model is solved and the seismic response is analyzed. Finally, an engineering example is used to verify the calculation method in this paper, and the results are compared with the shaking table test and numerical simulation. It shows that the calculation model proposed in this paper is safe and reasonable for the seismic design and analysis of the slope supported by prestressed anchors with frame structure.

Seismic Isolation Response and Parameter Influence Analysis of Nuclear Power Plant during Great Earthquake

2012 ◽  
Vol 166-169 ◽  
pp. 2275-2282 ◽  
Author(s):  
Wen Guang Liu ◽  
Rui Dong Wang ◽  
Lei Hua ◽  
Wen Fu He
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Seismic Response ◽  
Energy Absorption ◽  
Nuclear Power ◽  
Parameter Analysis ◽  
Great Earthquake ◽  
Lumped Mass ◽  
Earthquake Energy ◽  
Reactor Structure

In this paper, the behavior of the structure of a pressurized water reactor (PWR) nuclear power plant (NPP) in China, is taken into consideration during a great earthquake especially beyond the design benchmark. The effects of earthquake energy absorption are analyzed using simplified multi-lumped mass system. The effects of site conditions, post yield stiffness, yield force on isolated reactor structure (IRS) are also discussed. The results show that isolation technology can significantly reduce seismic response of the reactor structure and achieve preferable earthquake energy absorption of the IRS beyond the design benchmark during a great earthquake. Earthquake wave characteristics and isolation layer parameters have direct effects on seismic response and the results of parameter analysis can provide reference for a correct and logical design of IRS.

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