scholarly journals Finite Element Model-based Design of Stiffened Welded Plated Structures Subjected to Combined Loading

Author(s):  
Balázs Kövesdi

Resistance calculation of steel bridges with orthotropic plates subjected to combined loading situation (bending moment, shear and transverse forces called as M-V-F interaction) can be challenging for designers due to the interactive stability behavior and combined buckling phenomena. The current EN 1993-1-5 standard provides a design method using analytical design equations checking the pure (bending, shear and patch loading) and interaction resistances separately. This design process is complex in the case of steel bridges, especially for box-section bridges having numerous longitudinal and transverse stiffeners. Finite Element Model (FEM) based design can provide suitable design tools for efficient and accurate resistance calculation of these structure types. However, within the modelling process there are numerous questions to be answered regarding material models and imperfections to ensure required accuracy and safe resistance. A new standard prEN 1993-1-14 is currently under development which will provide design rules to finite element model-based design of steel structures, having the aim to answer the main part of the above mentioned questions and standardize the design process. The current paper discusses and demonstrates the methodology of the FEM based design for welded plated structures. Benchmark example for a Hungarian steel box-section bridge subjected to combined loading situation is presented. Effect of different meshing, imperfection combinations and material models are presented and evaluated in the paper. Efficiency of the numerical model and the obtained resistance on the input parameters are evaluated and design example is given for the application of the FEM based design method.

2021 ◽  
Author(s):  
Zwelihle Ndlovu ◽  
Dawood Desai ◽  
Thanyani Pandelani ◽  
Harry Ngwangwa ◽  
Fulufhelo Nemavhola

This study assesses the modelling capabilities of four constitutive hyperplastic material models to fit the experimental data of the porcine sclera soft tissue. It further estimates the material parameters and discusses their applicability to a finite element model by examining the statistical dispersion measured through the standard deviation. Fifteen sclera tissues were harvested from porcine’ slaughtered at an abattoir and were subjected to equi-biaxial testing. The results show that all the four material models yielded very good correlations at correlations above 96 %. The polynomial (anisotropic) model gave the best correlation of 98 %. However, the estimated material parameters varied widely from one test to another such that there would be needed to normalise the test data to avoid long optimisation processes after applying the average material parameters to finite element models. However, for application of the estimated material parameters to finite element models, there would be needed to consider normalising the test data to reduce the search region for the optimisation algorithms. Although the polynomial (anisotropic) model yielded the best correlation, it was found that the Choi-Vito had the least variation in the estimated material parameters thereby making it an easier option for application of its material parameters to a finite element model and also requiring minimum effort in the optimisation procedure. For the porcine sclera tissue, it was found that the anisotropy more influenced by the fiber-related properties than the background material matrix related properties.


2012 ◽  
Vol 443-444 ◽  
pp. 751-756
Author(s):  
Li Jun Suo ◽  
Xia Guang Hu

In China, it is fact that porous concrete base has been used in the construction of asphalt pavement in recent years because porous concrete base has good performance. However, Reasonable design method has not been put forward so far. Therefore, it is necessary to analyze load stress and thermal stress of asphalt pavement which includes porous concrete base in order to put forward theoretical basis for pavement design method. In the paper, three–dimension finite element model of asphalt pavement, which includes porous concrete base and asphalt surface, is created for the purpose of studying load stress and thermal stress of porous concrete base in asphalt pavement. Based on numerical method of three–dimension finite element model, finite element software, such as ANSYS, is employed to study load stress and thermal stress of porous concrete base in asphalt pavement. After that, the effect of different factors on stress is studied, and the factors include thickness of surface, thickness of base and ratio of base’s modulus to foundation’s modulus. Finally, calculation results for stress are compared with each other, and it shows that load stress of porous concrete base decreases with increase of base’s thickness, while thermal stress of porous concrete base increases with increase of base’s thickness. Load stress and thermal stress of porous concrete base decrease with increase of surface’s thickness. Load stress and thermal stress of porous concrete base increase with increase of ratio of base’s modulus to foundation’s modulus.


Heliyon ◽  
2020 ◽  
Vol 6 (11) ◽  
pp. e05297
Author(s):  
Gbétoglo Charles Komadja ◽  
Sarada Prasad Pradhan ◽  
Amulya Ratna Roul ◽  
Babatunde Adebayo ◽  
Jean Baptiste Habinshuti ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document