A Nonlinear Programming Paradigm for Hybrid Elements Formulation Towards High-Performance Collapse Simulations

面向高性能塌陷模拟的混合单元公式非线性编程范式

• 批准号: 1634575
• 负责人: Konstantinos Papakonstantinou
• 金额: $ 29.69万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634575&HistoricalAwards=false
• 关键词: Nonlinear; Programming; Paradigm; Hybrid; Elements

In a great variety of engineering simulations, including structural collapse analysis, consideration of nonlinear effects is indispensable. Various structural systems exhibit important nonlinearities under extreme loads, both in terms of geometry and material, and a realistic evaluation of structural behavior has been forcing researchers, engineering practice and building codes to resort to increasingly sophisticated nonlinear analysis approaches. Accurate and computationally efficient assessment of nonlinear phenomena is hence of vital importance towards sustainable structural designs of enhanced safety. Modern structural analysis efforts focus therefore in estimating structural damage and performance all the way up to collapse. Reliably predicting the behavior of a structural system until its collapse has significant economic and life safety implications. The main objectives of this research is to circumvent several deficiencies emerging in collapse and highly nonlinear simulations and to upgrade the quality, efficiency and accuracy of difficult structural analysis problems. Apart from the important scientific advancements in numerical analysis of structural engineering problems and the societal and economic benefits in relation to improved structural design, safer structures and effective failure predictions, this research can also contribute to a much wider academic spectrum. Similar phenomena of large elastic and inelastic displacements are of particular interest in multiple scientific fields and applications, and research outcomes can thus help the solution of related computational problems in numerous areas.An original hybrid element formulation based on a new nonlinear programming paradigm will be studied in this research. The exact kinematic expressions used are the essential properties that enable high-performance collapse simulations, namely allow for accuracy, coarse discretization, computational speed, algorithmic robustness and locking-free elements, even with very large inelastic displacements. Towards these goals, the total potential energy functional will be hybridized through Lagrange multipliers that assure compatibility and will be evaluated at collocation points within each element. This procedure results to a hybrid beam-column finite element, whereas structural analysis is formulated and treated as a pure nonlinear programming problem, seeking optima in terms of energy. This concept unlocks an entirely new research path, having the potential to outperform conventional linearization schemes and integrating the philosophy of nonlinear structural analysis with nonlinear programming concepts and the abundance of sophisticated methods in the field. Overall, this research project will advance the quality of collapse simulations, will facilitate improved and physically consistent damage limit state definitions, will pose new scientific and computational paradigms, and will push the limits of computational efficacy in demanding and computationally intensive large scale structural problems.

在包括结构性崩溃分析在内的各种工程模拟中，对非线性效应的考虑是必不可少的。在几何和材料方面，各种结构系统在极端载荷下表现出重要的非线性，对结构行为的现实评估一直在迫使研究人员，工程实践和建筑法规诉诸越来越复杂的非线性分析方法。因此，对非线性现象的准确和计算有效评估是对增强安全性的可持续结构设计至关重要的。因此，现代结构分析工作的重点是估算结构损害和性能一直以至于崩溃。可靠地预测结构系统的行为，直到其崩溃具有重大的经济和生命安全意义为止。 这项研究的主要目的是规避在崩溃和高度非线性模拟中出现的几种缺陷，并提高困难结构分析问题的质量，效率和准确性。除了对结构工程问题的数值分析以及与改善结构设计，更安全的结构和有效的失败预测有关的数值分析以及社会和经济利益的重要科学进步外，这项研究还可以促进更广泛的学术范围。大型弹性和非弹性位移的类似现象在多个科学领域和应用中特别感兴趣，因此，研究结果可以帮助众多领域中相关的计算问题解决方案。基于新的非线性编程范式的原始混合元件配方将在这项研究中研究。所使用的精确运动表达式是实现高性能崩溃模拟的必要特性，即允许准确性，粗离散，计算速度，算法鲁棒性和无锁定元素，即使具有非常大的非弹性位移也是如此。朝向这些目标，将通过Lagrange乘数杂交总势能功能，这些乘数可以确保兼容性，并将在每个元素内的搭配点进行评估。该过程导致混合梁列有限元素，而结构分析则被制定并视为纯粹的非线性编程问题，在能量方面寻求Optima。这个概念解锁了一条全新的研究路径，具有胜过传统的线性化方案的潜力，并将非线性结构分析的哲学与非线性编程概念以及该领域的丰富方法相结合。总体而言，该研究项目将提高崩溃模拟的质量，将有助于改善和物理上一致的伤害限制状态定义，构成新的科学和计算范式，并将在苛刻和计算强度的大规模结构问题上推动计算功效的限制。

项目成果

Geometrically exact hybrid beam element based on nonlinear programming

基于非线性规划的几何精确混合梁单元

• DOI: 10.1002/nme.6663
• 发表时间: 2021
• 期刊: International Journal for Numerical Methods in Engineering
• 影响因子: 2.9
• 作者: Lyritsakis, Charilaos M.;Andriotis, Charalampos P.;Papakonstantinou, Konstantinos G.
• 通讯作者: Papakonstantinou, Konstantinos G.

Nonlinear programming approach to a shear-deformable hybrid beam element for large displacement analysis

用于大位移分析的剪切变形混合梁单元的非线性编程方法

• 发表时间: 2019
• 期刊: COMPDYN Proceedings
• 作者: Lyritsakis, C.M.;Andriotis, C.P.;Papakonstantinou, K.G.
• 通讯作者: Papakonstantinou, K.G.

Nonlinear Programming Hybrid Beam-Column Element Formulation for Large-Displacement Elastic and Inelastic Analysis

• DOI: 10.1061/(asce)em.1943-7889.0001483
• 发表时间: 2018-10
• 期刊: Journal of Engineering Mechanics
• 影响因子: 3.3
• 作者: C. Andriotis;K. Papakonstantinou;V. Koumousis

Hysteretic Beam Finite-Element Model Including Multiaxial Yield/Capacity Surface Evolution with Degradations

• DOI: 10.1061/(asce)em.1943-7889.0001767
• 发表时间: 2020-09-01
• 期刊: JOURNAL OF ENGINEERING MECHANICS
• 影响因子: 3.3
• 作者: Amir, M.;Papakonstantinou, K. G.;Warn, G. P.
• 通讯作者: Warn, G. P.

Scaled Spherical Simplex Filter and State-Space Damage-Plasticity Finite-Element Model for Computationally Efficient System Identification

• DOI: 10.1061/(asce)em.1943-7889.0001945
• 发表时间: 2022-02
• 期刊: Journal of Engineering Mechanics
• 影响因子: 3.3
• 作者: M. Amir;K. G. Papakonstantinou;G. Warn