Seismic Performance of a Deficient Reinforced Concrete Test Frame with Infill Walls

2011 ◽  
Vol 27 (3) ◽  
pp. 817-834 ◽  
Author(s):  
Efe G. Kurt ◽  
Barış Binici ◽  
Özgür Kurç ◽  
Erdem Canbay ◽  
Akpınar ◽  
...  
Keyword(s):  
Ground Motion ◽  
Time History ◽  
Test Method ◽  
Damage State ◽  
Infill Wall ◽  
Damage States ◽  
Scale Levels ◽  
Observed Damage ◽  
Nonlinear Time History ◽  
Element Removal

A two-story, three-bay RC frame with code incompliant seismic design and detailing is tested using continuous pseudodynamic test method for three scale levels of Düzce ground motion. The ground motion produced minimum, significant, and severe damage states on the test structure. Diagonal cracking of the infill wall, column damage in the form of cover spalling and rebar buckling, and complete disintegration of the infill wall were the important observed damage events for the three scale levels, respectively. Nonlinear time history analyses were able to estimate the story displacement response with reasonable accuracy. The importance of element removal for near collapse damage state is unfolded. Tracing the local engineering demand parameters such as strains and curvature was found to be extremely difficult.

Probabilistic Performance Assessment of Retrofitted Horizontally Curved Multi-Frame RC Box-Girder Bridges

2017 ◽  
Vol 11 (04) ◽  
pp. 1750010 ◽  
Author(s):  
Hossein Pahlavan ◽  
Behzad Zakeri ◽  
Gholamreza Ghodrati Amiri
Keyword(s):  
Bridge Deck ◽  
Fragility Curves ◽  
Time History ◽  
Damage State ◽  
Box Girder Bridges ◽  
Box Girder ◽  
Horizontally Curved ◽  
Girder Bridges ◽  
Damage States ◽  
Nonlinear Time History

Bridge horizontal deck curvature and the prevalence of in-span hinges in multi-frame RC box-girder bridges have reinforced this class of bridge to response with unique dynamic behavior during seismic excitations. This paper assesses the impacts of 10 different retrofit strategies on the vulnerability of curved multi-frame RC box-girder bridges with multi-column bents based on nonlinear time history analyses in OpenSEES. Consistent with HAZUS-MH definitions, fragility curves corresponding to four damage states at the component and system levels are developed for various bridge deck radii. The results indicate that combinations of retrofit strategies should be used to enhance the desirable level of bridge performance. Moreover, the most effective retrofit strategy in reducing probable damage for a given intensity is dependent on the bridge deck radius and is a function of the damage state of interest.

scholarly journals FRP Composite in Mitigating Seismic Risk of RC Structures in Near-Fault Regions with/without Aftershocks

2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Vui Van Cao ◽  
Son Quang Pham
Keyword(s):  
Plastic Hinge ◽  
Time History ◽  
Damage State ◽  
Rc Structures ◽  
Seismic Sequences ◽  
Near Fault ◽  
Damage Indices ◽  
Aftershock Sequences ◽  
Nonlinear Time History ◽  
Original Frame

The literature related to earthquakes and fibre reinforced polymer (FRP) retrofitting can be divided into two main categories: (1) the applications of FRP to retrofit structures subjected to single traditional earthquakes and (2) the effects of mainshock-aftershock sequences on original structures (without FRP retrofitting). Research on using FRP to mitigate the risk of pulse-type mainshock-aftershock sequences for reinforced concrete (RC) structures located in near-fault regions is hardly found in the literature and is thus the aim of this study. To achieve this aim, a four-storey RC frame, near-fault mainshocks, and seismic sequences were selected. The frame was retrofitted using FRP wraps at plastic hinge locations. Nonlinear time history and damage analyses of the original and FRP-retrofitted frames subjected to these near-fault mainshocks and seismic sequences were conducted. The results showed that aftershocks significantly increase the damage indices of the frames, shifting the damage state of the original frame from severe damage to collapse and the damage state of the FRP-retrofitted frame from light damage to moderate damage. FRP retrofitting successfully reduced the risk of seismic sequences by reducing the damage two levels, shifting the damage state of the original frame from collapse to moderate damage.

Seismic Performance Analysis of the Special-Shaped Frame Column Structure on Multi-Dimensional Seismic

2011 ◽  
Vol 90-93 ◽  
pp. 1644-1648
Author(s):  
Dong Qiang Xu ◽  
Mei Mei He
Keyword(s):  
Ground Motion ◽  
Time History ◽  
Regular Structure ◽  
Frame Structure ◽  
Nonlinear Time History Analysis ◽  
Weak Links ◽  
Column Structure ◽  
Structure Torsion ◽  
Torsional Component ◽  
Nonlinear Time History

The article considers the two horizontal components of ground motion and torsional component, to do nonlinear time history analysis both on regular and irregular shaped column frame structure models. The results show that torsional component of ground motion haves some impact on torsion reaction of structures, stiffness of irregular shaped column frame structure is uneven, and angle of columns are greater than that of the regular structure; torsion haves some impact on the torque of structure, the torque increases of corner columns is maximum, so corner columns are weak links in shaped column structure, considered fully during the seismic design.

Response of Transmission Lines under Three-Dimensional Seismic Excitations

2012 ◽  
Vol 166-169 ◽  
pp. 2259-2264
Author(s):  
Li Tian ◽  
Hong Nan Li ◽  
Wen Ming Wang
Keyword(s):  
Transmission Line ◽  
Ground Motion ◽  
Transmission Lines ◽  
Three Dimensional ◽  
Time History ◽  
Maximum Response ◽  
Nonlinear Time History Analysis ◽  
Seismic Excitations ◽  
Practical Engineering ◽  
Nonlinear Time History

The behavior of transmission line under three-dimensional seismic excitations is studied by numerical simulation. According to a practical engineering, the transmission towers are modeled by frame elements and the transmission lines are modeled by cable element account for the nonlinearity of the cable. The effects of single-dimensional, two-dimensional and three-dimensional ground motions on the responses of transmission line are investigated using nonlinear time history analysis method, respectively. The results indicate that the longitudinal maximum response of transmission lines can be obtained considering longitudinal ground motion excitation only. The transverse maximum response of transmission lines can be obtained considering transverse ground motion excitation only. Neglecting multiple nature of ground motion in analysis will significantly underestimate the vertical responses of the transmission lines. To obtain an accurate seismic response of transmission lines, three-dimensional ground motion inputs are required.

scholarly journals A Wavelet-based Approach for Truncating Pulse-like Records

2021 ◽  
Author(s):  
Vicky Dimakopoulou ◽  
Michalis Fragiadakis ◽  
Ioannis Taflampas
Keyword(s):  
Ground Motion ◽  
Near Field ◽  
Time History ◽  
Response Spectra ◽  
Degree Of Freedom ◽  
Seismic Performance Assessment ◽  
Analysis And Design ◽  
Nonlinear Time History Analyses ◽  
Ground Motion Records ◽  
Nonlinear Time History

Abstract The seismic performance assessment of structures using truncated pulse-like ground motion records is discussed. It is shown that it is possible to truncate pulse-like signals using a novel wavelet-based definition that identifies the duration of the predominant velocity pulse. The truncated time history can efficiently reproduce the increased seismic demand that near-field records typically produce. Substituting the original ground motion with the truncated signal, significantly accelerates structural analysis and design. The truncated signal is the part of the original accelerogram that coincides with the duration of the predominant pulse, which is identified using a wavelet-based procedure, previously proposed by the authors. Elastic and inelastic response spectra and nonlinear time history analyses for SDOF (single-degree-of-freedom) systems are first studied. Subsequently a nine-storey steel frame is examined in order to demonstrate the performance of the proposed approach on a multiple-degree-of-freedom system. The proposed approach is found very efficient for pulse-like ground motions, while it is also sufficient for many records that are not characterized as such.

scholarly journals Effect of Ground Motion Directionality on Fragility Characteristics of a Highway Bridge

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Swagata Banerjee Basu ◽  
Masanobu Shinozuka
Keyword(s):  
Ground Motion ◽  
Dimensional Space ◽  
Fragility Curves ◽  
Time History ◽  
Transportation Systems ◽  
Nonlinear Time History Analysis ◽  
Response Analysis ◽  
Seismic Fault ◽  
Principal Axes ◽  
Nonlinear Time History

It is difficult to incorporate multidimensional effect of the ground motion in the design and response analysis of structures. The motion trajectory in the corresponding multi-dimensional space results in time variant principal axes of the motion and defies any meaningful definition of directionality of the motion. However, it is desirable to consider the directionality of the ground motion in assessing the seismic damageability of bridges which are one of the most vulnerable components of highway transportation systems. This paper presents a practice-oriented procedure in which the structure can be designed to ensure the safety under single or a pair of independent orthogonal ground motions traveling horizontally with an arbitrary direction to structural axis. This procedure uses nonlinear time history analysis and accounts for the effect of directionality in the form of fragility curves. The word directionality used here is different from “directivity” used in seismology to mean a specific characteristic of seismic fault movement.

scholarly journals Evaluation of seismic performance measures for MDOF RC structures subjected to simulated and real ground motions

2020 ◽  
Vol 323 ◽  
pp. 02003
Author(s):  
Shaghayegh Karimzadeh ◽  
Aysegul Askan ◽  
Ahmet Yakut
Keyword(s):  
Ground Motion ◽  
Seismic Performance ◽  
Performance Measures ◽  
Ground Motions ◽  
Time History ◽  
Motion Simulation ◽  
Ground Motion Simulation ◽  
Nonlinear Time History Analyses ◽  
Nonlinear Time History ◽  
Simulated Ground Motions

Nonlinear time history analyses of structures require full time series of ground motion records. For regions with sparse seismic networks or potential large earthquakes, ground motion simulation has gained more attention in recent years. Simulated records are required to be generated using regional input dataset and then verified against existing recorded ground motions of past events. To use simulated ground motions in engineering applications, estimation of reliable seismic demand parameters is essential. In this study, the real and simulated records of the 2009 L’Aquila, Italy earthquake with (Mw=6.3) are investigated for their use in engineering practice. In the first step, misfits are evaluated for alternative seismological measures (peak values, duration and frequency as well as energy content of the time histories). Next, varying multi-degree-of-freedom reinforced concrete structures with different number of stories are selected. Numerical models of the structures are performed in the OpenSees platform. Seismic performance measures in terms of inter-story drift ratio for the selected structures are assessed through nonlinear time history analyses for both the real and simulated ground motions. Then, the misfits are estimated in terms of structural demand parameters. Results reveal a good fit between the seismological and engineering demand misfits for the selected ground motion simulation approaches.

Failure Mechanism Study of Bridge Retainer in Earthquake

2013 ◽  
Vol 295-298 ◽  
pp. 2049-2053
Author(s):  
Yun Zhang ◽  
Bei Li ◽  
Liu Bin Yan
Keyword(s):  
Time History ◽  
Element Model ◽  
Nonlinear Time History Analysis ◽  
Mechanism Study ◽  
Damage State ◽  
Calculation Results ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Nonlinear Time History ◽  
Failure Types

Taking a typical continuous girder bridge for example, the text builds spatial beam finite element model. By nonlinear time history analysis method, it analyzes bridge transverse pounding and the retainer strength in different strength levers earthquake. According to bridge pier failure and fragility theory and retainer section moment-curvature analysis, it puts forward retainer failure types in different strength levers earthquake. The calculation results show that it is irrational to design retainer section and reinforcement based on structure requirement. The structural retainer failure types have uncertainty without considering bridge seismic fortification goal. Though it appears on ductility failure, the damage state is very serious.

scholarly journals Fragility Curve Analysis of Medium Cable Stayed Bridge

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Masrilayanti Masrilayanti ◽  
Ade Prayoga Nasution ◽  
Ruddy Kurniawan ◽  
Jafril Tanjung ◽  
Sarmayenti Sarmayenti
Keyword(s):  
Fragility Curves ◽  
Pushover Analysis ◽  
Time History ◽  
Fragility Curve ◽  
Seismic Load ◽  
Fragility Function ◽  
Cable Stayed Bridge ◽  
Damage States ◽  
Probabilistic Values ◽  
Nonlinear Time History

Abstract The seismic performance of a bridge can be shown by analyzing the vulnerability of the structure in resisting an earthquake motion and then developing into fragility curves. This study presents a convenient method to establish the fragility curve for the cable-stayed bridge. For this purpose, three spans cable-stayed bridge is assessed using a series of seismic loads in different intensities to ensure that the structure was experiencing damage in several conditions. The fragility curve was obtained by analyzing the structure using Nonlinear Time History (NTHA) and Pushover Analysis. The ground motions of the earthquake were subjected to the bridge in different intensities, which were scaled from the initial ground motion. Hereafter, the structure’s ductilities were developed into the fragility curves as the responses of the bridge. HAZUS standard is used for classifying the damages of the bridge, which are grouped into; slight, moderate, extensive, and complete due to the seismic load. The values of the damage states were generated to the fragility curves using the probabilistic values of the damage states. To ensure the validity of the data statistically, Kolmogorov-Smirnov test was conducted to the fragility function. The result revealed that the fragility curve was qualified as the lognormal distribution.

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