Nonlinear Finite Element Analysis of Stiffened T-Shaped Thin-Walled Concrete-Filled Steel Tube Composite Columns

2012 ◽  
Vol 193-194 ◽  
pp. 1461-1464
Author(s):  
Bai Shou Li ◽  
Ai Hua Jin

Based on the characteristics of the special-shaped concrete-filled steel tubes and consideration of material nonlinearity of constitutive relation, stimulation of 6 T-shaped thin-walled ribbed and un-ribbed concrete-filled steel tube short columns is implemented, as well as comparable analysis of stress, strain, displacement and bearing capacity, through the finite element analysis software ANSYS. The result indicates that the rib can effectively improve the ductility, delaying the buckling occurs, which enhances the core concrete confinement effect, so as the stimulated ultimate bearing capacity which is greater than nominal ultimate bearing capacity.

Author(s):  
Guochang Li ◽  
Zhichang Zhan ◽  
Zhijian Yang ◽  
Yu Yang

The concrete-filed square steel tube with inner I-shaped CFRP profiles short columns under bi-axial eccentric load were investigated by the finite element analysis software ABAQUS. The working mechanism of the composite columns which is under bi-axial eccentric load are investigated by using the stress distribution diagram of steel tube concrete and the I-shaped CFRP profiles. In this paper, the main parameters; eccentric ratio, steel ratio, steel yield strength, concrete compressive strength and CFRP distribution rate of the specimens were investigated to know the mechanical behavior of them. The interaction between the steel tube and the concrete interface at different characteristic points of the composite columns were analyzed. The results showed that the ultimate bearing capacity of the concrete-filed square steel tube with inner I-shaped CFRP profiles short columns under bi-axial eccentric load decrease with the increase of eccentric ratio, the ultimate bearing capacity of the composite columns increase with the increase of steel ratio, steel yield strength, concrete compressive strength and CFRP distribution rate. The contact pressure between the steel tube and the concrete decreased from the corner zone to the flat zone, and the contact pressure decreased from the mid-height cross section to other sections.


2014 ◽  
Vol 525 ◽  
pp. 568-572
Author(s):  
Yang Feng Wu ◽  
Hong Mei Zhang

A new composite strengthening method that the CFST short column was strengthened with concrete filled steel tube was presented. Through the finite element analysis of five specimens with strengthening circular concrete filled steel tube columns and a specimen without strengthening circular concrete filled steel tube to explore the impact of the outer layer of concrete strength grade, external pipe wall thickness for the ultimate bearing capacity of concrete filled steel tube columns. The results show that with the increase of the outer pipe wall thickness, double concrete filled steel tube column yield strength and ultimate strength have increased. As the outer concrete strength grade increased as the specimen bearing capacity increased. When the concrete strength grade greater than C40, the improvement of concrete strength for specimen ultimate bearing capacity is not great.


2011 ◽  
Vol 255-260 ◽  
pp. 45-48 ◽  
Author(s):  
Ya Feng Xu ◽  
Xin Zhao ◽  
Yi Fu

Based on experimental research, the bearing performance of the new column (steel tube-reinforced concrete composite columns combination strengthened with angle steel and CFRP) has been studied in detail by finite element method. A finite element model is established based on a series of assumption. The load-displacement curves are obtained. The influence of steel ratio and thickness of CFRP layers to the bearing capacity is analyzed too. The result shows that both the steel ratio and the thickness of CFRP layers have great contribution to the axial load capacity. The finite element analysis results and theoretical analysis which are in good agreement show that simulation results are generally right.


2011 ◽  
Vol 311-313 ◽  
pp. 1889-1893
Author(s):  
Ya Wen Du ◽  
Hong Yu Lin

Finite element analysis on three trusses was carried out in order to study the performance of combined truss with steel tube and concrete filled steel tube. The first specimen was a RHS truss, the second one was a combined truss with steel tube and concrete filled steel tube, and the third one was a concrete-filled steel tube truss. The results show that the finite element model can reflect the static performance of combined truss and can carry out the affective parameters analysis, which can offer theory evidence for engineering application of combined truss. The damage of three trusses was all due to the joint failure and the failure mode was all punishing shearing failure, but the concrete filled changed by the failure place of joints. The bearing capacity of three trusses was controlled by the jionts and the strength and stiffness of jionts were increased by the concrete filled in the chord, therefore the bearing capacity of trusses was increased while the deformation of trusses was decreased. In combined truss with steel tube and concrete filled steel tube, the concrete-filled steel tube joints can improve the bearing capacity and the steel tube joint can satisfy the requirements of deformation, which have obvious advantages in the engineering application.


Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1098 ◽  
Author(s):  
Xuetao Lyu ◽  
Yang Xu ◽  
Qian Xu ◽  
Yang Yu

This study investigated the axial compressive performance of six thin-walled concrete-filled steel tube (CFST) square column specimens with steel bar stiffeners and two non-stiffened specimens at constant temperatures of 20 °C, 100 °C, 200 °C, 400 °C, 600 °C and 800 °C. The mechanical properties of the specimens at different temperatures were analyzed in terms of the ultimate bearing capacity, failure mode, and load–displacement curve. The experiment results show that at high temperature, even though the mechanical properties of the specimens declined, leading to a decrease of the ultimate bearing capacity, the ductility and deformation capacity of the specimens improved inversely. Based on finite element software ABAQUS, numerical models were developed to calculate both temperature and mechanical fields, the results of which were in good agreement with experimental results. Then, the stress mechanism of eight specimens was analyzed using established numerical models. The analysis results show that with the increase of temperature, the longitudinal stress gradient of the concrete in the specimen column increases while the stress value decreases. The lateral restraint of the stiffeners is capable of restraining the steel outer buckling and enhancing the restraint effect on the concrete.


2014 ◽  
Vol 578-579 ◽  
pp. 269-273
Author(s):  
Bing Li ◽  
Shuang Meng ◽  
Wei Hao Wang

The objective of this paper is to provide the references through finite element analysis for steel tube concrete beams bearing capacity settlement. The paper verified the correctness of the constitutive relation of concrete, the correctness and the model through the establishment of the concrete damaged plasticity model with recycled concrete details in the finite element analysis software ABAQUS. Then the stress characteristics of steel pipe concrete beam in bending condition under different substitution rate could be found through model calculation. The result is that the mid span bending - strain curve from simulation agreed to the experimental results, and the model is proved correct. Finally it came to the conclusions. Other things being equal, the recycled concrete filled square tube changed a lot in bending state when the substitution rate grows, but it didn’t occur to the circular one. In the meantime, the writer proposed the conjecture on the bearing capacity calculation of the two types of structure.


2014 ◽  
Vol 578-579 ◽  
pp. 263-268
Author(s):  
Bing Li ◽  
Qi Zhang ◽  
Shuang Meng

The paper achieved the nonlinear analysis of bearing capacity of recycled concrete filled steel tubular short columns by using finite element analysis software ABAQUS. In order to meet the finite element analysis the writer put forward the modified formula of recycled concrete constitutive relationship of core, and elaborate d the contact at the interface of steel tube and the core concrete and related modeling points. Finally the load-deformation curves of the finite element analysis and test results coincide well. It indicates that the modified formula of recycled concrete constitutive relationship can better meet the requirements of analyzing bearing capacity of recycled concrete filled circular steel tubular columns under compressive Loading by using ABAQUS. Through the simulation experiment, it is useful for us to obtain the ultimate reliable bearing capacity of the similar structure member.


Author(s):  
V. Panwar ◽  
R.K. Dutta

Purpose: The purpose of this study is to investigate the ultimate bearing capacity of the rectangular footing resting over layered sand using finite element method. Design/methodology/approach: Finite element analysis was used to investigate the dimensionless ultimate bearing capacity of the rectangular footing resting on a limited thickness of upper dense sand layer overlying limitless thickness of lower loose sand layer. The friction angle of the upper dense sand layer was varied from 41° to 46° whereas for the lower loose sand layer it was varied from 31° to 36°. Findings: The results reveal that the dimensionless ultimate bearing capacity was found to increase up to an H/W ratio of about 1.75 beyond which the increase was marginal. The results further reveal that the dimensionless ultimate bearing capacity was the maximum for the upper dense and lower loose sand friction angles of 46° and 36°, while it was the lowest for the upper dense and lower loose sands corresponding to the friction angle of 41° and 31°. For H/W = 0.5 and 2, the dimensionless bearing capacity decreases with the increase in the L/W ratio from 0.5 to 6 beyond which the dimensionless ultimate bearing capacity remains constant for all combinations of parameters. The results were presented in nondimensional manner and compared with the previous studies available in literature. Research limitations/implications: The analysis is performed using a ABAQUS 2017 software. The limitation of this study is that only finite element analysis is performed without conducting any experiments in the laboratory. Further the study is conducted only for the vertical loading. Practical implications: This proposed numerical study can be used to predict the ultimate bearing capacity of the rectangular footing resting on layered sand. Originality/value: The present study gives idea about the ultimate bearing capacity of rectangular footing when placed on layered sand (dense sand over loose sand) as well as the effect of thickness of top dense sand layer on the ultimate bearing capacity. The findings could be used to calculate the ultimate bearing capacity of the rectangular footing on layered sand.


Sign in / Sign up

Export Citation Format

Share Document