Neural network for earthquake selection in structural time history analysis

1994 ◽  
Vol 23 (3) ◽  
pp. 303-319 ◽  
Author(s):  
M. Cheng ◽  
N. Popplewell
Keyword(s):  
Neural Network ◽  
Time History ◽  
Time History Analysis ◽  
History Analysis ◽  
Structural Time ◽  
Earthquake Selection

scholarly journals Comparison of Scaling Ground Motions Using Arithmetic with Logarithm Values for Spectral Matching Procedure

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Rui Zhang ◽  
Dong-sheng Wang ◽  
Xiao-yu Chen ◽  
Hong-nan Li
Keyword(s):  
Ground Motions ◽  
Time History ◽  
Response Spectra ◽  
Time History Analysis ◽  
Spectral Matching ◽  
Moment Resisting Frame ◽  
History Analysis ◽  
Moment Resisting ◽  
Structural Responses ◽  
Structural Time

In recent studies, spectral matching is the most commonly proposed method for selecting earthquake records for time-history analysis of structures. However, until now, there have been no serious investigations of the effects of coordinate values on the scaling of ground motions. This paper investigated the influence of using arithmetic and logarithmic values of response spectra in spectral matching procedures (i.e., ASM and LSM methods) on the results of nonlinear structural time-history analysis. Steel moment resisting frame structures of the 3-, 9-, and 20-stories, which represent low-, medium-, and high-rise buildings, respectively, were used as examples. Structural benchmark responses were determined by calculating the arithmetic mean and median of peak interstory drift ratio (PIDR) demands based on the three record sets developed by the American SAC Steel Project. The three record sets represent seismic hazard levels with 50%, 10%, and 2% probabilities exceeded in 50 years, and their average acceleration spectra were also taken as the target spectrum. Moreover, another 40 record components for selection were scaled both by ASM and LSM methods. The seven components whose spectra were best compatible with the target spectra were selected for the structural time-history analysis. The scale factors obtained by the LSM method are nearly larger than that of the ASM method, and their ranking and selection of records are different. The estimation accuracies of structural mean (median) responses by both methods can be controlled within an engineering acceptable range (±20%), but the LSM method may cause larger structural responses than the ASM method. The LSM method has a better capacity for reducing the variability of structural responses than the ASM method, and this advantage is more significant for longer-period structures (e.g., 20-story structure) with more severe nonlinear responses.

scholarly journals Assessment of Earthquake Destructive Power to Structures Based on Machine Learning Methods

2020 ◽  
Vol 10 (18) ◽  
pp. 6210
Author(s):  
Ruihao Zheng ◽  
Chen Xiong ◽  
Xiangbin Deng ◽  
Qiangsheng Li ◽  
Yi Li
Keyword(s):  
Neural Network ◽  
Machine Learning ◽  
Ground Motions ◽  
Low Frequency ◽  
Time History ◽  
Time History Analysis ◽  
Machine Learning Algorithms ◽  
Learning Networks ◽  
History Analysis ◽  
Deep Layers

This study presents a machine learning-based method for the destructive power assessment of earthquake to structures. First, the analysis procedure of the method is presented, and the backpropagation neural network (BPNN) and convolutional neural network (CNN) are used as the machine learning algorithms. Second, the optimized BPNN architecture is obtained by discussing the influence of a different number of hidden layers and nodes. Third, the CNN architecture is proposed based on several classical deep learning networks. To build the machine learning models, 50,570 time-history analysis results of a structural system subjected to different ground motions are used as training, validation, and test samples. The results of the BPNN indicate that the features extraction method based on the short-time Fourier transform (STFT) can well reflect the frequency-/time-domain characteristics of ground motions. The results of the CNN indicate that the CNN exhibits better accuracy (R2 = 0.8737) compared with that of the BPNN (R2 = 0.6784). Furthermore, the CNN model exhibits remarkable computational efficiency, the prediction of 1000 structures based on the CNN model takes 0.762 s, while 507.81 s are required for the conventional time-history analysis (THA)-based simulation. Feature visualization of different layers of the CNN reveals that the shallow to deep layers of the CNN can extract the high to low-frequency features of ground motions. The proposed method can assist in the fast prediction of engineering demand parameters of large-number structures, which facilitates the damage or loss assessments of regional structures for timely emergency response and disaster relief after earthquake.

PERILAKU STRUKTUR BAJA TIPE MRF DENGAN BEBAN LATERAL BERDASARKAN SNI 1726-2012 DAN METODE PERFORMANCE BASED PLASTIC DESIGN (PBPD)

2014 ◽  
Vol 13 (1) ◽  
Author(s):  
Nidiasari Jati Sunaryati Eem Ikhsan
Keyword(s):  
Pushover Analysis ◽  
Time History ◽  
Time History Analysis ◽  
Plastic Design ◽  
History Analysis ◽  
Non Linear ◽  
Static Pushover Analysis

Struktur rangka baja pemikul momen merupakan jenis struktur baja tahan gempa yang populer digunakan. Daktilitas struktur yang tinggi merupakan salah satu keunggulan struktur ini, sehingga mampu menahan deformasi inelastik yang besar. Dalam desain, penggunaan metode desain elastis berupa evaluasi non-linear static (Pushover analysis) maupun evaluasi non-linear analisis (Time History Analysis) masih digunakan sebagai dasar perencanaan meskipun perilaku struktur sebenarnya saat kondisi inelastik tidak dapat digambarkan dengan baik. Metode Performance-Based Plastic Design (PBPD) berkembang untuk melihat perilaku struktur sebenarnya dengan cara menetapkan terlebih dahulu simpangan dan mekanisme leleh struktur sehingga gaya geser dasar yang digunakan adalah sama dengan usaha yang dibutuhkan untuk mendorong struktur hingga tercapai simpangan yang telah direncanakan. Studi dilakukan terhadap struktur baja 5 lantai yang diberi beban gempa berdasarkan SNI 1726, 2012 dan berdasarkan metode PBPD. Hasil analisa menunjukkan bahwa struktur yang diberi gaya gempa berdasarkan metode PBPD mencapai simpangan maksimum sesuai simpangan rencana dan kinerja struktur yang dihasilkan lebih baik .

scholarly journals Record-to-record variability and code-compatible seismic safety-checking with limited number of records

2021 ◽  
Author(s):  
Fatemeh Jalayer ◽  
Hossein Ebrahimian ◽  
Andrea Miano
Keyword(s):  
Seismic Hazard ◽  
Linear Time ◽  
Time History ◽  
Time History Analysis ◽  
Seismic Safety ◽  
Hazard Curve ◽  
History Analysis ◽  
Non Linear ◽  
Seismic Hazard Curve ◽  
Cloud Analysis

AbstractThe Italian code requires spectrum compatibility with mean spectrum for a suite of accelerograms selected for time-history analysis. Although these requirements define minimum acceptability criteria, it is likely that code-based non-linear dynamic analysis is going to be done based on limited number of records. Performance-based safety-checking provides formal basis for addressing the record-to-record variability and the epistemic uncertainties due to limited number of records and in the estimation of the seismic hazard curve. “Cloud Analysis” is a non-linear time-history analysis procedure that employs the structural response to un-scaled ground motion records and can be directly implemented in performance-based safety-checking. This paper interprets the code-based provisions in a performance-based key and applies further restrictions to spectrum-compatible record selection aiming to implement Cloud Analysis. It is shown that, by multiplying a closed-form coefficient, code-based safety ratio could be transformed into simplified performance-based safety ratio. It is shown that, as a proof of concept, if the partial safety factors in the code are set to unity, this coefficient is going to be on average slightly larger than unity. The paper provides the basis for propagating the epistemic uncertainties due to limited sample size and in the seismic hazard curve to the performance-based safety ratio both in a rigorous and simplified manner. If epistemic uncertainties are considered, the average code-based safety checking could end up being unconservative with respect to performance-based procedures when the number of records is small. However, it is shown that performance-based safety checking is possible with no extra structural analyses.

Time-History Analysis of a Super-Large Storage Tank Under Seismic Excitation

2013 ◽  
Author(s):  
Fan Bu ◽  
Caifu Qian
Keyword(s):  
Storage Tank ◽  
Time History ◽  
Time History Analysis ◽  
Radial Deformation ◽  
Tank Wall ◽  
History Analysis ◽  
Medium Level ◽  
Wall Deformation ◽  
Slow Progress ◽  
Earthquake Action

In this paper, two finite element models are established for a super-large storage tank with or without a floating roof on the medium level. Time-history analysis with consideration of fluid-solid coupling for the deformation of tank wall and medium sloshing during or after an earthquake is performed with the emphasis on the effects of the floating roof. It is found that the upper part of tank is more sensitive to the earthquake action than the lower part. The wind girders and the reinforcing rings play a big role in limiting the radial deformation of the upper part of the tank wall. The floating roof has little effect on the tank wall deformation, but it is effective in suppressing the medium sloshing during the earthquake. After the earthquake, the radial deformation of the tank wall attenuates quickly, but the sloshing attenuation of the medium presents a slow progress and the floating roof inhibits the sloshing attenuation of the medium.

Nonlinear Dynamic Analysis of the Damping Frame Structure System

2012 ◽  
Vol 594-597 ◽  
pp. 886-890 ◽  
Author(s):  
Gan Hong ◽  
Mei Li ◽  
Yi Zhen Yang
Keyword(s):  
Energy Dissipation ◽  
Seismic Response ◽  
Nonlinear Dynamic ◽  
Time History ◽  
Time History Analysis ◽  
Frame Structure ◽  
Force Model ◽  
Operating Characteristics ◽  
Restoring Force ◽  
History Analysis

Abstract. In the paper, take full account of energy dissipation operating characteristics. Interlayer shear-frame structure for the analysis of the Wilson-Θmethod ELASTOPLASTIC schedule, the design of a nonlinear dynamic time history analysis procedure. On this basis, taking into account the restoring force characteristics of the energy dissipation system, the inflection point in the restoring force model treatment, to avoid a result of the calculation results of distortion due to the iterative error. A frame structure seismic response time history analysis results show that: the framework of the energy dissipation significantly lower than the seismic response of the common framework, and its role in the earthquake when more significant.

Elastic-Plastic Time History Analysis of MR Damping Structure Based on LQG Algorithm

2016 ◽  
Vol 858 ◽  
pp. 145-150
Author(s):  
Yu Liang Zhao ◽  
Zhao Dong Xu
Keyword(s):  
Optimal Control ◽  
Time History ◽  
Mr Damper ◽  
Time History Analysis ◽  
Control Force ◽  
Control Effect ◽  
Damping Force ◽  
Optimal Control Strategy ◽  
Elastic Plastic ◽  
History Analysis

This paper discussed an elastic-plastic time-history analysis on a structure with MR dampers based on member model, in which the elastoplastic member of the structure is assumed to be single component model and simulated by threefold line stiffness retrograde model. In order to obtain better control effect, Linear Quadratic Gaussian (LQG) control algorithm is used to calculate the optimal control force, and Hrovat boundary optimal control strategy is used to describe the adjustable damping force range of MR damper. The effectiveness of the MR damper based on LQG algorithm to control the response of the structure was investigated. The results from numerical simulations demonstrate that LQG algorithm can effectively improve the response of the structure against seismic excitations only with acceleration feedback.

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