arXiv subjects

Suiyin Chen

Publications and source records attributed to Suiyin Chen.

6 recordsLinked to original sources

arXiv2025

Exact finite element formulation of quasi-3D beam based on analytical internal force fields for accurate static analysis of FG sandwich beams

This paper presents a novel exact finite element formulation of quasi-3D beam for high-fidelity analysis of functionally graded sandwich beams. Unlike conventional displacement-based elements that rely on approximate interpolation functions or existing exact finite element methods requiring closed-form solutions of generalized displacements, the proposed approach constructs an exact beam element from analytical expressions of internal forces. The method innovatively integrates force-based beam element formulation with the exact finite element framework through a systematic implementation procedure. Firstly, analytical expressions for internal forces are derived by applying differential equilibrium equations, geometric relations, and constitutive equations. These expressions are then used to obtain integral forms of generalized displacements expressed in terms of internal force parameters. Subsequently, nodal generalized displacements are defined, and their relationship with internal force parameters is established via the consistency condition. Finally, exact shape functions are derived from interpolation definitions, and the exact stiffness matrix and equilibrium equations are formulated using the principle of virtual work. To further enhance solution accuracy, modified cross-sectional stiffness matrices accounting for equilibrium-based stress distributions are incorporated. Comprehensive numerical examples demonstrate that the proposed element achieves superior solution accuracy and computational efficiency compared to conventional methods, validating its potential for precise structural analysis of complex beam structures with material gradients.

math.NA↗

arXiv2025

A Kriging-HDMR-based surrogate model with sample pool-free active learning strategy for reliability analysis

In reliability engineering, conventional surrogate models encounter the "curse of dimensionality" as the number of random variables increases. While the active learning Kriging surrogate approaches with high-dimensional model representation (HDMR) enable effective approximation of high-dimensional functions and are widely applied to optimization problems, there are rare studies specifically focused on reliability analysis, which prioritizes prediction accuracy in critical regions over uniform accuracy across the entire domain. This study develops an active learning surrogate model method based on the Kriging-HDMR modeling for reliability analysis. The proposed approach facilitates the approximation of high-dimensional limit state functions through a composite representation constructed from multiple low-dimensional sub-surrogate models. The architecture of the surrogate modeling framework comprises three distinct stages: developing single-variable sub-surrogate models for all random variables, identifying the requirements for coupling-variable sub-surrogate models, and constructing the coupling-variable sub-surrogate models. Optimization mathematical models for selection of design of experiment samples are formulated based on each stage's characteristics, with objectives incorporating uncertainty variance, predicted mean, sample location and inter-sample distances. A candidate sample pool-free approach is adopted to achieve the selection of informative samples. Numerical experiments demonstrate that the proposed method achieves high computational efficiency while maintaining strong predictive accuracy in solving high-dimensional reliability problems.

cs.LG↗

arXiv2025

A force-based beam element model based on the modified higher-order shear deformation theory for accurate analysis of FG beams

In this paper, a force-based beam finite element model based on a modified higher-order shear deformation theory is proposed for the accurate analysis of functionally graded beams. In the modified higher-order shear deformation theory, the distribution of transverse shear stress across the beam's thickness is obtained from the differential equilibrium equation, and a modified shear stiffness is derived to take the effect of transverse shear stress distribution into consideration. In the proposed beam element model, unlike traditional beam finite elements that regard generalized displacements as unknown fields, the internal forces are considered as the unknown fields, and they are predefined by using the closed-form solutions of the differential equilibrium equations of higher-order shear beam. Then, the generalized displacements are expressed by the internal forces with the introduction of geometric relations and constitutive equations, and the equation system of the beam element is constructed based on the equilibrium conditions at the boundaries and the compatibility condition within the element. Numerical examples underscore the accuracy and efficacy of the proposed higher-order beam element model in the static analysis of functionally graded sandwich beams, particularly in terms of true transverse shear stress distribution.

cs.CE↗

arXiv2025

System reduction-based approximate reanalysis method for statically indeterminate structures with high-rank modification

Efficient structural reanalysis for high-rank modification plays an important role in engineering computations which require repeated evaluations of structural responses, such as structural optimization and probabilistic analysis. To improve the efficiency of engineering computations, a novel approximate static reanalysis method based on system reduction and iterative solution is proposed for statically indeterminate structures with high-rank modification. In this approach, a statically indeterminate structure is divided into the basis system and the additional components. Subsequently, the structural equilibrium equations are rewritten as the equation system with the stiffness matrix of the basis system and the pseudo forces derived from the additional elements. With the introduction of spectral decomposition, a reduced equation system with the element forces of the additional elements as the unknowns is established. Then, the approximate solutions of the modified structure can be obtained by solving the reduced equation system through a pre-conditioned iterative solution algorithm. The computational costs of the proposed method and the other two reanalysis methods are compared and numerical examples including static reanalysis and static nonlinear analysis are presented. The results demonstrate that the proposed method has excellent computational performance for both the structures with homogeneous material and structures composed of functionally graded beams. Meanwhile, the superiority of the proposed method indicates that the combination of system reduction and pre-conditioned iterative solution technology is an effective way to develop high-performance reanalysis methods.

cs.CE↗

arXiv2025

CSP-free adaptive Kriging surrogate model method for reliability analysis with small failure probability

In the field of reliability engineering, the Active learning reliability method combining Kriging and Monte Carlo Simulation (AK-MCS) has been developed and demonstrated to be effective in reliability analysis. However, the performance of AK-MCS is sensitive to the size of Candidate Sample Pool (CSP), particularly for systems with small failure probabilities. To address the limitations of conventional AK-MCS that relies on CSP, this paper proposes a CSP-free AK-MCS. The proposed methodology consists of two stages: surrogate model construction and Monte Carlo simulation for estimating the failure probability. In the stage of surrogate model construction, the surrogate model is iteratively refined based on the representative samples selected by solving the optimization problem facilitated by Particle Swarm Optimization (PSO) algorithm. To achieve an optimal balance between solution accuracy and efficiency, the penalty intensity control and the density control for the experimental design points are introduced to modify the objective function in optimization. The performance of the proposed methodology is evaluated using numerical examples, and results indicate that by leveraging an optimization algorithm to select representative samples, the proposed CSP-free AK-MCS overcomes the limitations of conventional CSP-based AK-MCS and exhibits exceptional performance in addressing small failure probabilities.

cs.CE↗

arXiv2025

A cable finite element formulation based on exact tension field for static nonlinear analysis of cable structures

This paper presents a numerically exact cable finite element model for static nonlinear analysis of cable structures. The model derives the exact expression of the tension field using the geometrically exact beam theory coupled with the fundamental mechanical characteristics of cables. The equations for the cable element are formulated by addressing the equilibrium conditions at the element boundaries and ensuring compatibility within the element. Unlike previous studies that typically provide explicit expressions for cable models, this study develops a formulation that emphasizes numerical precision and broad applicability. It achieves this by deriving linearized equations with implicit expressions incorporating integrals. The proposed model accurately computes internal forces and deformation states, and determines the unstrained length of the cable. Additionally, it accounts for the variability in cross-sectional stiffness along the cable's length. The paper discusses solution implementations using the complete tangent matrix and element internal iterations. The effectiveness of the proposed cable element is demonstrated through numerical examples.

cs.CE↗