Structural Mechanics of Engineering Constructions and BuildingsStructural Mechanics of Engineering Constructions and BuildingsСтроительная механика инженерных конструкций и сооружений1815-52352587-8700Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)4830810.22363/1815-5235-2025-21-5-441-461DEEXQAAnalytical and numerical methods of analysis of structuresАналитические и численные методы расчета конструкцийResearch ArticleTriangular Layered Finite Element Method for Reinforced Concrete SlabsМетод многослойных треугольных конечных элементов для железобетонных плит перекрытияhttps://orcid.org/0009-0003-2819-3107MawloodDara A.МавлудДара A.

Master student, Department of Building Structures and Controlled Systems, Institute of Civil Engineering

магистрант кафедры строительных конструкций и управляемых систем, Инженерно-строительный институт

dara.mawloud@univsul.edu.iqhttps://orcid.org/0000-0001-5271-99042779-8314KoyankinAlexandr A.КоянкинАлександр Александрович

Candidate of Technical Sciences, Associate Professor of the Department of Building Structures and Controlled Systems, Institute of Civil Engineering

кандидат технических наук, доцент кафедры строительных конструкций и управляемых систем, Инженерно-строительный институт

KoyankinAA@mail.ruSiberian Federal UniversityСибирский федеральный университет15122025215VOL 21, NO5 (2025)ТОМ 21, №5 (2025)44146131012026Copyright ©; 2025, Mawlood D.A., Koyankin A.A.Copyright ©; 2025, Мавлуд Д.A., Коянкин А.А.2025Mawlood D.A., Koyankin A.A.Мавлуд Д.A., Коянкин А.А.https://creativecommons.org/licenses/by-nc/4.0https://journals.rudn.ru/structural-mechanics/article/view/48308

This study presents an advanced layered triangular finite element method for modeling reinforced concrete (RC) slabs, incorporating material nonlinearity based on a refined global-local plate theory. The RC slab's cross-section is discretized into concrete and steel layers, each modeled as an individual plate element with distinct material properties. The proposed formulation independently considers displacement field variables and out-of-plane stress components, enabling precise nodal stress determination through constitutive relationships. A three-node triangular element maintaining C1-continuity is employed for spatial discretization, with governing equations derived using a triangular layered plate theory. Benchmark verification studies confirm the method’s computational accuracy and efficiency, with ultimate deflection predictions exhibiting errors ranging from 2.59% (minimum) to 11.2% (maximum). Comprehensive numerical tests demonstrate that the proposed triangular layered finite element approach delivers high-precision solutions while significantly reducing computational expense.

Представлен усовершенствованный многослойный треугольный метод конечных элементов для моделирования железобетонных плит, учитывающий нелинейность материала на основе усовершенствованной глобально-локальной теории пластин. Поперечное сечение железобетонной плиты разбито на бетонные и стальные слои, представляющие собой отдельные элементы с различными свойствами материала. Предлагаемая формулировка независимо учитывает переменные поля смещений и компоненты напряжений вне плоскости, что позволяет точно устанавливать узловое напряжение с помощью определяющих соотношений. Для пространственной дискретизации используется треугольный элемент с тремя узлами, поддерживающий непрерывность порядка C1, а основные уравнения получены с использованием теории многослойных треугольных пластин. Сравнительные проверочные исследования подтвердили точность вычислений и эффективность метода, при этом погрешность результатов расчета прогиба составляет от 2,59 % (минимум) до 11,2 % (максимум). Всесторонние численные эксперименты демонстрируют, что предложенный метод многослойных треугольных конечных элементов обеспечивает высокую точность решений при значительном снижении вычислительных затрат.

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