Papers by Keyword: Nonlinear Finite Element Analysis

Abstract: A new simple, efficient and accurate finite element model denoted as FEM-B is developed for the analysis of structural behavior of FRP strengthened RC beams with bond-slip effect. Geometric nonlinearity and material nonlinear properties of concrete and steel rebar are accounted for this model. Concrete, steel, FRP and adhesive are modelled as Solid 65, Link 180, Shell181 and Solid 45 respectively. Concrete is modelled using Nitereka and Neal’s model for compression, isotropic and linear elastic model before cracking for tension and strength gradually reduces to zero after cracking, whereas steel is assumed to be elastic perfectly plastic material. The material of FRP is considered to be linearly elastic until rupture, and adhesive is assumed to be linearly elastic. The bond slip between concrete, adhesive and FRP is based on the bilinear law, which is modelled using spring element Combin 39.The developed new finite element model FEM-B is validated against experimental results, and demonstrates to be effective for the structural analysis of FRP strengthened RC beams.

Abstract: The fatigue problem of concrete has long been studied through many different methods. However, the fatigue process and failure patterns of concrete structures have never been well simulated due to the lack of comprehensive understanding of the material properties under fatigue loads. In order to carry out an accurate simulation of the fatigue behavior of concrete structures, this paper proposes a new damage theory based fatigue constitutive model for concrete. The present model adopts two damage variables to describe the degradation of macro mechanical properties of concrete under tension and compression, respectively. And the tensile and compressive damage evolutions are related to the corresponding effective stress spaces. Specifically, by implementing the present model into the nonlinear finite element package, the bending fatigue process of a concrete beam is simulated. Meanwhile a set of numerical tests are presented, through which the validity and effectiveness of the proposed model for the simulation of concrete structures are illustrated.

Abstract: This research selected Z-shaped section column joints in RC frame as the investigating object and considered the mechanical parameters extracted from physical model test results, proposed the finite element model of concrete damaged plasticity. Combining concrete damage plasticity model parameters on ABAQUS of concrete constitutive relationship from appendix C of Code for design of concrete structures (GB50010-2010), add the concept of damage factor to Energy equivalence principle, construct finite element model of Z-shaped column joints in RC frame, and simulated the test process under horizontal cyclic loading. The analysis results indicate that the finite element model can perfectly simulate action. It can reflect the mechanical properties of Z-shaped column joints in frame under horizontal cyclic loading, which is proved correct and reliable.

Abstract: The nonlinear finite element analysis of the rigid steel column base connection with anchor bolt under biaxial bending, including the column base stiffeners, base plate, anchor bolts and other nonlinear interaction analysis, to provide a frame of reference for the rigid steel column base connection’ designed.

Abstract: The determining of m value in “m” method has great significance to force analysis of pile foundation buried segments. In this paper, a finite element software is used for the nonlinear finite element analysis of elastic long pile under the horizontal force action, and combined with the related provisions and formulas for “m” method given in 《Code for Pile Foundation of Harbour Engineering》, a accurate m value can be obtained conveniently. Then based on this method and by the single factor analysis, a more systematic study was made to the related factors, and obtained the influence law of various factors to m value.

Abstract: Not only the geometrical imperfection induced by welding but also cutouts will influence the buckling of large-scale thin-walled steel cylindrical shell under wind loading. Based on the practical cylindrical shells of a desulphurizing absorption tower, in consideration of the correlation between welding induced imperfection and circular cutouts, the influence of cutout position on buckling of cylinder under wind loading is investigated by nonlinear finite element method. The results indicate that the buckling capacity varies slightly when the cutout position moves along meridional direction in the neighboring region of welding imperfection. The buckling capacity varies significantly when the cutout position moves circumferentially as the cutout is located in the welding imperfection. The buckling capacity reaches the minimum value as the cutout is located in the buckle center of cylindrical shells without cutout.

Abstract: 4 finite element models of ANSYS were constructed according to the masonry wall specimens of the experimental study. A material nonlinear finite element analysis by the finite element calculation software ANSYS on masonry walls strengthened by SGFRP under the horizontal cyclic loads combined with constant gravity loads was performed. The load-displacement curves of the models obtained from ANSYS simulation were described. The ultimate loads of the 3 models strengthened by SGFRP increased significantly, and the fiber length affect the bearing capacity and the deformation capacity of the wall. The results of the nonlinear finite element analysis of the models agree well to the experimental results. Some effective and reasonable reinforcement suggestions are proposed.

Abstract: With the rapid development of finite element technique and computer technology, the design of the cold punching mould CAD / CAM with CAE analysis is changing the way that traditional craft manufacture mold, especially the development and application of stamping simulation software, make the stamping die design and processing and quantitative, can advance analysis of stamping process program, finally got the ideal pressing parameter, realize the automation of design, save resources and reduce the dependence on experience and reduce the demand for skilled workers. Based on nonlinear dynamic finite element software ANSYS / ls-dyna continuous function, simulation of sheet metal forming process and unloading plate deformation, forming process, at any time throughout the von mises stress nephogram should rebound results and strain value and unloading plate materials, help us better analysis to understand the changes of the internal material sheet metal stamping process.

Abstract: In this paper, the anti-bending function of the concrete beam is simulated by using ANSYS software. The simulated quantity include crack loads, yield load, ultimate load, deflection, crack and crush, stress distribution, strain distribution, movement of neutral axis and so on. The simulated model is a actual structure test. As a result, the value of the yield load, the ultimate load, the deflection are consisted with the actual loads .The method may be used on simulation of structure tests, or used in teaching of some colleges.

Abstract: In this paper, several FRP-reinforced concrete beams are modelled using a recently developed one-dimensional two-node layered composite beam element which accounts for the bond-slip between reinforcing bars and the surrounding concrete. Effect of different surfaces of FRP reinforcing bars on the structural response of FRP-reinforced concrete beams with bond-slip effect is also investigated. It is found that the type of rebar surface has a significant influence on bond strength and structural behaviour, and that the grain-covered surface provides the best bond between the FRP rebars and concrete, the smooth surface the worst, and FRP rebars with ribbed and braided surfaces perform similarly. Keywords: Bond-slip; Composite beam element; FRP-reinforced concrete beam; Nonlinear finite element analysis