Narrow Results

This paper investigates the soil-reticulated Soil Structure (shell-frame) Interaction (SSI) and its seismic response analysis under vertically incident seismic waves. By establishing the mechanical model of the three-dimensional oblique sliding friction seismic isolator (3D OSFSI), the effectiveness in reducing vertical responses is analyzed. The simulation of seismic waves and the automatic application of equivalent nodal forces are realized by using viscoelastic artificial boundaries and ABAQUS software combined with Python scripts. A comparison of the model with and without consideration of SSI found that the SSI effect will increase the peak value of nodes and the axial force of rods, three-dimensional seismic isolation can reduce the structural response, and the effect of different soil parameters is significant, weak soil due to the characteristics of the structural acceleration response of the smallest, so the mesh shell should be considered in the analysis of the seismic response of the site conditions and the effect of soil parameters.

In this work, two types of models for a closed-cell Al foam with 80% porosity were established by Digimat and ABAQUS. The compression characteristics of the Al foam-filled stainless steel tube structure with both Al foam models were simulated and compared in combination with experiments. The results showed that Al foam-filled tubes presented higher peak compressive force compared with unfilled stainless steel tube. Compared with the crushable Al Foam model established by ABAQUS, the Digimat model could intuitively observe the plastic deformation in the cells of the Al foam-filled structure. However, the simulated results derived from Digimat software were slightly different from the experimental result. In general, the crushable-foam model embedded in ABAQUS can better match the experimental results from a macro perspective.

The capability of a commercial industrial tool, ABAQUS, to simulate the critical damage mechanisms in stiffened composite panels has been evaluated. The analysis and conclusions are supported by experimental results. The focus is on skin–stringer separation during compressive loading. Results show that the advanced degradation modeling capabilities present in commercial codes today may lead to an accurate characterization of the deep postbuckling range behavior and the collapse of stiffened composite panels. Compared to current design practice, where the first indication of ply failure or the onset of damage propagation is taken as the failure load, the methods used here provide a way to exploit the reserves in composite structures. It is concluded that implementing degradation mechanisms (composite ply and adhesive interface degradation) presents a significant improvement to simulate accurately the deep postbuckling states and collapse for stiffened composite panels with adhesively bonded stringers. The nature of the final loss of load-carrying capacity for this type of structures, by composite ply and adhesive interface failure, driven by postbuckling deformation, makes this simulation approach essential.

This study utilizes the transfer matrix method to analyze the modified Timoshenko beam with and without cracks. The massless torsional spring is assumed to represent the section where the crack is located. The matrix equation is simplified using boundary conditions and solved using MATLAB. Additionally, the influence of different crack depths and positions on the first three natural frequencies is compared to finite element analysis using three common types of beams as examples. The results indicate that increasing the crack depth leads to a decrease in the natural frequency of the beam. However, the impact on certain specific positions is insignificant, with a maximum error between the two methods not exceeding 2.73%. Furthermore, the study investigates the influence of crack depth on natural frequency under different span-to-height ratios. The findings reveal that increasing the span-to-height ratio reduces the influence of crack depth on natural frequency, thereby validating the proposed method and its applicability in modified Timoshenko cracked beams.

It has been observed by performing simple and diagonal compression tests of cob wallettes that the structural behavior of cob is highly nonlinear. This paper presents the results obtained of the simulation of cob’s nonlinear monotonic behavior using two well-known finite element commercial packages. Pros and cons of different available constitutive material models are identified and discussed. Concrete (CONCR) and Concrete Damaged Plasticity (CDP) are considered as the constitutive material models that provide the more satisfactory results reproducing cob’s nonlinear monotonic behavior when using ANSYS and ABAQUS, respectively.

Dissipative processes such as viscoelasticity and current leakage are known to affect the electromechanical performance of dielectric elastomers. In this work, we describe a constitutive theory that couples electrostatics, large deformation, viscoelasticity and current leakage. We also implement this model in a commercial finite element solver ABAQUS by developing new user-defined elements. The method is used to study the effect of viscoelasticity and current leakage on the behavior of dielectric elastomers. Our finite element implementation will serve as a simulation platform to guide the design of practical dielectric elastomer transducers.

The free vibration frequency responses of the laminated composite structure with a cut-out of variable shapes (square/circular/elliptical), position (center/eccentric) and orientation (parallel/inclined) are investigated for the first time in this research including geometrical shapes. The eigenvalues are obtained computationally for the cut-out borne structure via a linear isoparametric finite element model of the composite structure in association with cubic-order of displacement kinematics. Also, a coupled code is prepared in MATLAB environment by joining the higher-order formulation and the simulation model (ABAQUS) to achieve the generic form to investigate the influential cut-out parameter (shape, size and position) on their eigenvalues. Further, a series of experimentations are carried out using the cut-out borne composite panel and compared with the computational frequency, including the experimental properties. Finally, the key behavior is surveyed through different kinds of numerical examples for various design constraint parameters including the cut-out relevant factors (shape, position and orientation) to show the subsequent inclusiveness of the proposed model.

The influences of crack and delamination on the natural frequency and strain energy release rate of the laminated doubly curved shell structure are computed via a commercial finite element tool (ABAQUS). The effect of individual damages (crack and delamination) is modeled using the virtual crack closure technique (VCCT), considering the curvature effect. Initially, the model validity is established by comparing the results with the available results in the open domain. Additionally, the model validity has been verified via in-house experimentation for frequency responses. Further, the natural frequency and strain energy release rate (SERR) have been calculated for the structure to examine the influences of the individual or combined effect of damages by varying the design-dependent input geometrical parameters. The inclusive characteristics of the current model in conjunction with geometrical configurations are summarized for subsequent references.

In this paper, the software of ABAQUS (One of the universal finite element analysis software) was used to do the simulation research on the steel tube filled with steel-reinforced concrete which subjected to the eccentric load after high temperature. The effect of temperature and slenderness ratio on the mechanical properties of the composite column was studied. Meanwhile, the simplified calculation formula of the stability bearing capacity of the composite column after high temperature was derived, and the calculated results show good agreement with the simulated results.

Based on the ring rolling theory, a mechanics model of ring rolling deflection system was established and ring rolling force expressions were deduced considering the effect of geometry nonlinear and physical nonlinear factors. The mechanics expressions of the roll-ring contact surface neutral angles and the force moment acting on the ring were obtained. Analyzing the mechanics expressions, the mechanics mechanism of the ring deflection in ring rolling was revealed. Furthermore, a ring rolling model was established by applying the finite element software ABAQUS, which verified the mechanism of the deflection of ring rolling. These conclusions are in good agreement with both the experiments and the actual ring rolling. It developed a base for further dynamics research of ring swing and improved the stability of the ring rolling process.

This paper aims to analyze the impact of material deletion and defects on composite material sabot. Choosing a certain type of penetrator made of composite material sabot, the penetrator's emission intensity is numerically studied using ABAQUS software. The corresponding stress nephograms and strain nephograms from numerical simulation were obtained, and a detailed analysis of them was carried out. The conclusion provides an important reference for studies on composite materials in the future.

Bond-slip constitutive of steel bar in the early age concrete is applied to the spring2 elements of ABAQUS to simulate the interaction between bar and concrete because of the existence of bond-slip phenomenon in the early age. Spring2 elements are set in the grids of concrete element and bar element which are coincident in the finite element model. What’s more, bond-slip constitutive relation is used as the material of spring2 elements. The finite element models of 6 reinfored concrete beams are built to analyze the effect of age of concrete (3days, 5days, 7days and 28days) and ratio of reinforcement (0.43%, 0.84% and 1.39%) for mechanical properties of beam. It was found that cracking moment, yield moment and ultimate moment of concrete beams are gradually increasing with the extend of age of concrete. Three days ago, carrying capacity of early age concrete beam developed rapidly. And it tends to be stable five days later. Increasing the rate of reinforcement can dramatically improve the mechanical properties of the beams. When the rate of reinforcement reached to some degree, its influence will be down.

In this paper, we do the research on the steel tube filled with steel-reinforced concrete subjected to Mechanical after high temperature by changing the temperature and the slender ratio. Influence of the temperature and slender ratio on the composite column was gotten by the research. It the stability formula of the composite column after high temperature was derived.

A Truss-Column pin-connected joint used in large-span steel structures is proposed in this paper. The European code is used to analyze and design the joints. The finite element analysis is conducted on four joints by the software ABAQUS. The full-scale model of the joints, as well as the large-scale, has been tested both under monotonic and repeated loads, the ultimate loads and the hysteretic curve of the joints are obtained. The results of the test indicate that the pin-connected joints have strong working behavior. Combined with the test and the calculation, it verifies the reliability of the calculation method. The tests make perfect the theory of the pin-connected calculation. The European code is viable and can be applied to long-span steel structures in China.

The constitutive model selected is the key to numerical analysis, which affects the reliability of analysis results directly. It is easy to use strain space plastic model to simulate softening constitutive behavior if the concrete material is beyond its limit stress. In this paper, an elastic-plastic constitutive model is established based on strain space plastic model, using Huang Kezhi-Zhang Yuangao’s three-parameters yield criterion to determine yield surface. The relationship between three parameters of yield criterion and uniaxial compression strength design value of concrete is presented. Using ABAQUS user material subroutine UMAT, the first derivation continuous equivalent uniaxial stress-strain curve is applied. The comparison between test results and calculation results demonstrates that the proposed model has a high calculation accuracy.

In order to study the mechanical performance of the double-layer high-strength spiral stirrup confined concrete circular column under axial compression load, based on the domestic and foreign scholars on the study of confined concrete, according to the test results, the finite element model of the double-layer high-strength spiral stirrup confined concrete circular column is simulated. Then the mechanical property of the high-strength spiral stirrup and concrete are analyzed. The results indicate that the simulation results are in good agreement with the test results. The double-layer high-strength spiral stirrup can restrain effectively horizontal deformation of reinforced concrete. The effective constraint has significant effect to improve the ultimate bearing capacity and ductility of reinforced concrete columns, and the results are inclined to safety. Therefore, the model can be used in nonlinear finite element analysis of the double-layer high-strength spiral stirrup confined concrete circular column.

In this paper, taking into account the effect of the stress wave, the ABAQUS finite element analysis software was used to carry out the simulation for the dynamic buckling of metal bar under axial step load. The bifurcation of strain time-history curve of the symmetric elements on the top and bottom surface of a metal bar were used to verify the critical buckling time, the critical buckling load and the modal graphs are obtained. Meantime the dynamic buckling induced the reflection of the stress wave is also analyzed. The results indicate that the critical buckling load after the reflection of the stress wave is much smaller than the load before the reflection. The longer the critical buckling time, the smaller the critical buckling load.