Correlating Finite Element Model of a Car Spot-welded Front-End Module in the Light of Modal Testing Data

Author(s):  
W.I.I. Wan Iskandar Mirza ◽  
M.N. Abdul Rani ◽  
M.A. Yunus ◽  
B. Athikary ◽  
M.S.M. Sani

Model updating methods can be adopted to improve the correlation level between the finite element model of a spot welded structure and its test model. However, in the presence of contact interfaces in the vicinity of the welded areas, improving the correlation level is problematic and challenging. An approach for correlating the finite element model of a welded structure with contact interfaces using finite element model updating and modal testing is proposed. The proposed approach was tested on a car front-end module structure that consisted of nine components and 76 resistance spot-welded joints used to assemble the components. CWELD and CELAS1 element connectors were used to represent the spot-welded joints and contact interfaces in the finite element modelling and updating. This approach was applied successfully to predict the modal parameters of the car spot-welded front-end module. The total error of the initial finite element model of the structure was reduced from 27.13% to 5.75%. The findings of this work suggest that the proposed approach has a great potential for use in investigating the dynamic behaviour of various spot-welded structures without a significant decline in accuracy.

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
B. Asgari ◽  
S. A. Osman ◽  
A. Adnan

The model tuning through sensitivity analysis is a prominent procedure to assess the structural behavior and dynamic characteristics of cable-stayed bridges. Most of the previous sensitivity-based model tuning methods are automatic iterative processes; however, the results of recent studies show that the most reasonable results are achievable by applying the manual methods to update the analytical model of cable-stayed bridges. This paper presents a model updating algorithm for highly redundant cable-stayed bridges that can be used as an iterative manual procedure. The updating parameters are selected through the sensitivity analysis which helps to better understand the structural behavior of the bridge. The finite element model of Tatara Bridge is considered for the numerical studies. The results of the simulations indicate the efficiency and applicability of the presented manual tuning method for updating the finite element model of cable-stayed bridges. The new aspects regarding effective material and structural parameters and model tuning procedure presented in this paper will be useful for analyzing and model updating of cable-stayed bridges.


2019 ◽  
Vol 22 (16) ◽  
pp. 3487-3502
Author(s):  
Hossein Moravej ◽  
Tommy HT Chan ◽  
Khac-Duy Nguyen ◽  
Andre Jesus

Structural health monitoring plays a significant role in providing information regarding the performance of structures throughout their life spans. However, information that is directly extracted from monitored data is usually susceptible to uncertainties and not reliable enough to be used for structural investigations. Finite element model updating is an accredited framework that reliably identifies structural behavior. Recently, the modular Bayesian approach has emerged as a probabilistic technique in calibrating the finite element model of structures and comprehensively addressing uncertainties. However, few studies have investigated its performance on real structures. In this article, modular Bayesian approach is applied to calibrate the finite element model of a lab-scaled concrete box girder bridge. This study is the first to use the modular Bayesian approach to update the initial finite element model of a real structure for two states—undamaged and damaged conditions—in which the damaged state represents changes in structural parameters as a result of aging or overloading. The application of the modular Bayesian approach in the two states provides an opportunity to examine the performance of the approach with observed evidence. A discrepancy function is used to identify the deviation between the outputs of the experimental and numerical models. To alleviate computational burden, the numerical model and the model discrepancy function are replaced by Gaussian processes. Results indicate a significant reduction in the stiffness of concrete in the damaged state, which is identical to cracks observed on the body of the structure. The discrepancy function reaches satisfying ranges in both states, which implies that the properties of the structure are predicted accurately. Consequently, the proposed methodology contributes to a more reliable judgment about structural safety.


Machines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 246
Author(s):  
Wei Guo ◽  
Ping Xu ◽  
Zhaofeng Yi ◽  
Jie Xing ◽  
Hui Zhao ◽  
...  

This paper proposes a variable stiffness collision post (VSCP) structure based on a uniform stiffness collision post (USCP) structure and performs stiffness matching optimization for VSCPs. A collision post structure assembled in a subway front-end frame can maintain the living space and absorb a certain amount of the kinetic energy of an impact. The experiment was applied on USCP, and the finite element model was verified experimentally. To investigate the effects of the stiffness parameters of VSCP on the specific energy absorption response (SEA_VSCP) and the area of intrusion response (S_In), response surface models fitted from design of experiment were adopted with the finite element model. In addition, a multiobjective optimization design was realized by using the global response search method and a Pareto frontier sequence was generated, which was based on the developed response surface model. It was found that the optimal value of SEA_VSCP and S_In responses cannot be achieved at the same time. Finally, a grey relational analysis is propounded to attain a desirable balance between SEA_VSCP and S_In from the Pareto frontier sequence under constraints of the peak crash force of VSCP and energy absorption of the front-end of cab car. The optimization result shows that the crashworthiness of VSCP is better than that of USCP.


Author(s):  
M.A.S. Aziz Shah ◽  
M.A. Yunus ◽  
A.M. Saman ◽  
M.N. Abdul Rani ◽  
A.R. Bahari ◽  
...  

2010 ◽  
Vol 163-167 ◽  
pp. 2843-2847
Author(s):  
Li Xian Wang ◽  
Sheng Kui Di

Based on random vibration theory, virtual response is obtained from the measured acceleration signal of Yantan Yellow River Bridge of Lanzhou under ambient excitation, Yantan Yellow River bridge's modal parameters were identified by using the peak picking and stochastic subspace identification, analyzed from theoretical and experimental aspects, compared with the finite element model results and verified the reliability of recognition results. The identified dynamic properties can be served as the basis in the finite element model updating, damage detection, condition assessment and health monitoring of the bridge.


2021 ◽  
Vol 15 (58) ◽  
pp. 114-127
Author(s):  
Jutao Wang ◽  
Zhenzhong Liu ◽  
Liju Xue

Modal frequencies are often used in structural model updating based on the finite element model, and metamodel technique is often applied to the corresponding optimization process. In this work, the Kriging model is used as the metamodel. Firstly, the influence of different correlation functions of Kriging model is inspected, and then the approximate capability of Kriging model is investigated via inspecting the approximate accuracy of nonlinear functions. Secondly, a model updating procedure is proposed based on the Kriging model, and the samples for constructing Kriging model are generated via the method of Optimal Latin Hypercube. Finally, a typical frame structure is taken as a case study and demonstrates the feasibility and efficiency of the proposed approach. The results show the Kriging model can match the target functions very well, and the finite element model can achieve accurate frequencies and can reliably predict the frequencies after model updating.


Sign in / Sign up

Export Citation Format

Share Document