András Pollák

59169672900

Publications - 4

Exploring the Impact of Fiber Content on the Mechanical Performance of Steel Fiber Reinforced Concrete: Consistency and Compaction Time Analysis

Szabolcs Fischer András Pollák Eszter Tóth

Publication Name: Lecture Notes in Networks and Systems

Publication Date: 2025-01-01

Volume: 1258 LNNS

Issue: Unknown

Page Range: 162-174

Description:

The evolution of building materials and technologies is imperative in response to the growing demands for large-scale infrastructure. Steel fiber-reinforced concrete (SFRC) has gained widespread usage due to its notable benefits, such as enhanced crack-bridging capacity and increased shear strength, reducing the need for traditional reinforcement. This study investigates the effects of varying fiber content and compaction times on the mechanical properties of SFRC. Laboratory tests were conducted on 24 different concrete mix designs, producing a total of 216 specimens, including blocks, cubes, and beams. The findings indicate that the optimal fiber content and compaction time significantly influence the compressive, flexural, and tensile strengths of SFRC. A detailed mathematical and statistical analysis highlights the importance of these parameters, providing insights for optimizing SFRC performance in construction. Future research directions are suggested to enhance further the understanding and application of SFRC in the construction industry.

Open Access: Yes

DOI: 10.1007/978-3-031-81799-1_16

Laboratory and Numerical Investigation of Pre-Tensioned Reinforced Concrete Railway Sleepers Combined with Plastic Fiber Reinforcement

Miklós Kuczmann Szabolcs Fischer I. Fekete Zoltán Major Richárd Nagy Szabolcs Szalai Mykola Sysyn Attila Németh Dmytro Kurhan Majid Movahedi Rad Sarah Khaleel Ibrahim Dániel Harrach Szabolcs Kocsis Szurke Vivien Jóvér Hanna Csótár Gusztáv Baranyai Bálint Molnár Klaudia Madarász András Pollák Bence Hermán László Gáspár

Publication Name: Polymers

Publication Date: 2024-06-01

Volume: 16

Issue: 11

Page Range: Unknown

Description:

This research investigates the application of plastic fiber reinforcement in pre-tensioned reinforced concrete railway sleepers, conducting an in-depth examination in both experimental and computational aspects. Utilizing 3-point bending tests and the GOM ARAMIS system for Digital Image Correlation, this study meticulously evaluates the structural responses and crack development in conventional and plastic fiber-reinforced sleepers under varying bending moments. Complementing these tests, the investigation employs ABAQUS’ advanced finite element modeling to enhance the analysis, ensuring precise calibration and validation of the numerical models. This dual approach comprehensively explains the mechanical behavior differences and stresses within the examined structures. The incorporation of plastic fibers not only demonstrates a significant improvement in mechanical strength and crack resistance but paves the way for advancements in railway sleeper technology. By shedding light on the enhanced durability and performance of reinforced concrete structures, this study makes a significant contribution to civil engineering materials science, highlighting the potential for innovative material applications in the construction industry.

Open Access: Yes

DOI: 10.3390/polym16111498

Technologies for Minimizing Track Degradation and Additional Dynamic Effects at Permanent Way-Railway Bridge Stiffness Transitions †

Szabolcs Fischer Zoltán Major Szabolcs Kocsis Szurke Bálint Molnár András Pollák Bence Hermán Szabolcs Kocsis Szürke

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

Railway tracks at bridge approaches experience significant vertical stiffness transitions, leading to adverse effects such as settlement and increased dynamic loads, accelerating track degradation. This study explores various structural solutions, including geosynthetics, reinforced ballast, transition slabs, under sleeper pads (USPs), under ballast mats (UBMs), jet grouting, and special rail fasteners. Despite their application, these solutions often fail due to their static nature. This paper introduces an adaptive approach using special rail fastenings with real-time adjustable stiffness. This system dynamically modifies rail support characteristics based on train speed and track conditions, improving track durability, ride quality, and maintenance strategies. The findings demonstrate the potential of adaptive systems to enhance railway infrastructure performance.

Open Access: Yes

DOI: 10.3390/engproc2025113046

Changes in the Properties of Thermal Insulation Materials Due to Environmental and Exposure Factors: Examination of Autoclaved Aerated Concrete Thermal Insulation Mineral Boards

Szabolcs Fischer David Bozsaky Attila Németh Dániel Harrach Gusztáv Baranyai Dániel Hegedűs András Pollák

Publication Name: Lecture Notes in Networks and Systems

Publication Date: 2026-01-01

Volume: 1768 LNNS

Issue: Unknown

Page Range: 91-99

Description:

The energy performance of buildings has become increasingly important, driven by efficiency, awareness, and sustainability goals. While attention often focuses on passive or zero-emission buildings, upgrading the thermal insulation of existing stock remains essential. In Hungary, many buildings still fail to meet current standards, from 19th-century apartments in Budapest to post-war panel blocks designed without thermal considerations. This study examined mineral-based insulation boards made from autoclaved aerated concrete under controlled exposure scenarios: cold winter (−20 °C), humid spring/autumn (10 °C, 90% RH), and hot summer (70 °C, 20% RH). Standardized tests assessed mass variation, compressive strength, thermal conductivity, and short-term water absorption. Results show that high humidity caused up to 14% loss of compressive strength and a 17–18% increase in thermal conductivity after 14 days, severely reducing insulation capacity. In contrast, extreme cold and heat induced only minor changes. Moisture was identified as the most critical factor compromising both mechanical stability and energy efficiency. The findings provide reproducible evidence of environmental sensitivity and underline the importance of durability assessments in designing and retrofitting energy-efficient buildings.

Open Access: Yes

DOI: 10.1007/978-3-032-13898-9_11