Géza Herczeg

58162531000

Publications - 5

Fuzzy Logic and Push-Out Test Innovations for Fiber-Reinforced Self-compacting Concrete Assessment

Oveys Ghodousian Majid Movahedi Rad Vahid Shafaie Géza Herczeg

Publication Name: Fib Symposium

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 855-862

Description:

This research addresses the deterioration of concrete infrastructures, emphasizing the efficacy of Fiber-Reinforced Self-Compacting Concrete (FRSCC) in repair applications. The study investigates the bond strengths between new and existing concrete layers, employing both experimental and numerical methods to evaluate traditional and innovative testing approaches, including slant shear and push-out tests. Results demonstrate that FRSCC, enhanced with polypropylene fibers, significantly improves structural resilience and mechanical properties. The introduction of fuzzy logic models further refines the prediction of bond strengths, offering a robust framework for future concrete technology advancements.

Open Access: Yes

DOI: DOI not available

Numerical Study of the Geogrid Reinforced Soil Wall Incorporating Strain-Softening Constitutive Soil Model

Seyed Ali Emamian Majid Movahedi Rad Vahid Shafaie Géza Herczeg Mahdi Salari

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 327-333

Description:

This study embarks on a numerical exploration of Geogrid Reinforced Soil Walls (GRSW), employing finite difference analysis to compare two soil constitutive models, highlighting the efficacy of a refined strain-softening model. This innovative approach markedly improves the prediction of GRSW performance, particularly aligning the safety factor more closely with real-world observations. Notably, the strain-softening model demonstrates a superior ability over the perfectly plastic model by significantly reducing the mean overall error in predicting maximum geogrid strain overall from 51% to 30%, reflecting a significant 41% improvement in precision, thereby presenting a significant tool for enhancing geotechnical design practices. The research underlines the potential of this model to elevate the safety and reliability of GRSW constructions, contributing to elevated design standards within the field of geotechnical engineering.

Open Access: Yes

DOI: 10.3233/ATDE240563

Numerical Investigation of Pre-Stressed Reinforced Concrete Railway Sleeper for High-Speed Application

Szabolcs Fischer Zoltán Major Szabolcs Szalai Mykola Sysyn Attila Németh Dmytro Kurhan Dóra Harangozó Majid Movahedi Rad Sarah Khaleel Ibrahim Dániel Harrach Szabolcs Kocsis Szurke Gusztáv Baranyai Géza Herczeg László Gáspár

Publication Name: Infrastructures

Publication Date: 2023-03-01

Volume: 8

Issue: 3

Page Range: Unknown

Description:

The current paper deals with the numerical investigation of a unique designed pre-stressed reinforced concrete railway sleeper for the design speed of 300 km/h, as well as an axle load of 180 kN. The authors applied different methodologies in their research: traditional hand-made calculations and two types of finite element software. The latter were AxisVM and ABAQUS, respectively. During the calculations, the prestressing loss was not considered. The results from the three methods were compared with each other. The hand-made calculations and the finite element modeling executed by AxisVM software are adequate for determining the mechanical inner forces of the sleeper; however, ABAQUS is appropriate for consideration of enhanced and sophisticated material models, as well as the stress-state of the elements, i.e., concrete, pre-stressed tendons, etc. The authors certified the applicability of these methodologies for performing the dimensioning and design of reinforced concrete railway sleepers with pre-stressing technology. The research team would like to continue their research in an improved manner, taking into consideration real laboratory tests and validating the results from FE modeling, special material models that allow calculation of crackings and their effects in the concrete, and so that the real pattern of the crackings can be measured by GOM Digital Image Correlation (DIC) technology, etc.

Open Access: Yes

DOI: 10.3390/infrastructures8030041

Geometrically nonlinear topology optimization of steel I-beams using BESO: a comparative study under multiple loading conditions

Gábor Csaba Soóki-Tóth Majid Movahedi Rad Muayad Habashneh Géza Herczeg Gábor Csaba Soóki-Tóth Somfai Attila Zsolt Zsombor Kamocsai Gábor Erika

Publication Name: Engineering Research Express

Publication Date: 2025-12-31

Volume: 7

Issue: 4

Page Range: Unknown

Description:

A geometrically nonlinear topology optimization method is presented in this paper for steel I-section beams, incorporating large displacement analysis to capture realistic structural behavior under flexural loads. The developed framework aims to enhance structural performance and material efficiency by optimizing the web region while preserving critical load paths. The optimization process is driven by enhancing the Bi-directional Evolutionary Structural Optimization (BESO) algorithm implemented in MATLAB and coupled with ABAQUS. Three beam configurations are analyzed under identical boundary and loading conditions to compare the performance of the optimized layout against traditional designs. To further assess the robustness of the proposed algorithm, two additional load scenarios, including a four-point bending test and a uniformly distributed load, are investigated. The results demonstrate that the optimized beam configurations reduce web material by 60% (volume fraction = 0.40) under 45 kN mid-span load while sustaining 55% higher load than the circular-opening beam (45 kN vs. 29 kN) with mean stress of 203.1 MPa, achieving 20% less web material than the conventional design and 18% higher complementary work (1.89 × 105 N mm) than the plain-web beam. The findings underline the value of incorporating geometric nonlinearity into topology optimization for producing high-performance, lightweight steel structures suitable for real-world engineering applications.

Open Access: Yes

DOI: 10.1088/2631-8695/ae242b

FATIGUE TOPOLOGY OPTIMIZATION UNDER CYCLIC LOADING FOR INNOVATIVE STRUCTURAL DESIGN

Majid Movahedi Rad Muayad Habashneh Géza Herczeg Gábor Erika Majid Movahedi Rad

Publication Name: Compdyn Proceedings

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 3389-3400

Description:

This study proposes a fatigue topology optimization approach for structural systems subjected to cyclic loading. Recognizing the impact of repeated loading on material endurance, the method incorporates fatigue considerations into the optimization process to enhance the durability and sustainability of load-bearing structures. By factoring in cyclic loading effects, this approach aims to reduce excessive material use while improving structural resilience, aligning with objectives for efficient and sustainable design. The proposed method is particularly useful in optimizing structural components in steel frameworks, where fatigue resistance and material efficiency are critical under dynamic loads. Emphasizing a balance between strength and durability, this study offers a practical tool for engineers aiming to design resilient structures that can endure cyclic stress without unnecessary material consumption. Furthermore, this framework is envisioned as a valuable solution for cyclic load environments, supporting more sustainable and resource-efficient engineering practices.

Open Access: Yes

DOI: 10.7712/120125.12660.25045