TY - JOUR AU - Juhász, Károly Péter AU - Schaul, Péter AU - Veres, Boglárka TI - Numerical and experimental investigation on synthetic macrofiber-reinforced concrete manhole exposed to railway loads JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - 20 PY - 2024 PG - 25 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e03093 UR - https://m2.mtmt.hu/api/publication/34785837 ID - 34785837 N1 - Budapest University of Technology and Economics, Department of Mechanics, Materials and Structures, Műegyetem rakpart 1-3, Budapest, 1111, Hungary Budapest University of Technology and Economics, Department of Construction Materials and Technologies, Műegyetem rakpart 1-3, Budapest, 1111, Hungary Kodolányi János University, Business Administration and Management, Rákóczi utca 25, Székesfehérvár, 8000, Hungary JKP STATIC Ltd, Budapest, Hungary Export Date: 12 April 2024 Correspondence Address: Juhász, P.K.; JKP STATIC Ltd, Reitter Ferenc utca 100 B/2/4, Hungary; email: office@jkp.hu AB - The refurbishment of railway lines and the installation of new tracks necessitate the construction of numerous concrete manholes; therefore, the optimization of manholes should be investigated. To this end, the use of innovative materials in addition to advanced design methods with realistic modeling is required. In the case of conservatively designed structures, there exists the possibility of redesigning the structure utilizing suitable fiber-reinforced concrete (FRC) only. The main advantage of synthetic macrofibers over steel is their complete corrosion resistance, which is essential in corrosive environments. Other advantages include their low carbon footprint, reduced construction time, and cost-effectiveness. This paper outlines the optimization process for a conventional cast-in-situ concrete manhole. The imperative for a monolithic construction system stems from the diverse geometries and distinct designs of individual pipe culverts, compounded by the often-challenging accessibility of installation sites. In the optimization phase, synthetic macrofiber reinforcement replaced conventional reinforcing steel bars, using advanced finite element analysis (FEA). The design was not conducted on an equivalent basis, resulting in potential variations in the load-carrying capacity between reinforced concrete (RC) and FRC manholes. Nevertheless, both are deemed suitable for the specified loads. The conventional design method used for RC and the advanced finite element design method used for FRC were scrutinized, taking into account the existing standard environment. Subsequently, a real-scale test was conducted to validate the calculations. Carbon footprint analyses were performed for both the original and proposed solutions, and the results were compared. The solution obtained in this study is unique and pioneering in terms of both the calculation method and the structural design, and the CO2 calculations validate its necessity. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, Balamurali AU - Priyanka, Raja AU - Anand, N. AU - Kiran, Tattukolla AU - Andrushia, A. Diana AU - Lublóy, Éva Eszter TI - A sustainable solution for mitigating environmental corrosion in the construction sector and its socio-economic concern JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - 20 PY - 2024 PG - 20 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e03089 UR - https://m2.mtmt.hu/api/publication/34785836 ID - 34785836 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Electronics and Communication Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, 1521, Hungary Export Date: 12 April 2024 Correspondence Address: Anand, N.; Department of Civil Engineering, India; email: nanand@karunya.edu AB - Corrosion in reinforced concrete (RC) structures is a typical occurrence, particularly in coastal locations. Corrosion occurs when steel reinforcement within concrete is exposed to environmental variables such as moisture, oxygen, and chloride ions, resulting in a chemical reaction that deteriorates the steel and degrades the concrete structure's overall function. In order to create effective mitigation techniques, it is critical to evaluate the impact of corrosion on various types of concrete. Chloride ions, often present in marine environments penetrate the concrete cover and reach the steel reinforcement, through pores. The water-cement ratio is a critical factor in concrete mix design. Excess water in the mix can result in the formation of larger and interconnected pores, during the hydration process. Further, improper curing conditions, such as insufficient moisture during the initial stages of hydration, can cause incomplete hydration and the formation of pores. Therefore use of high dense and highly alkaline concrete such as geopolymer concrete (which does not require water curing), can be employed to reduce the impact of corrosion. In the present study an attempt was created to examine the rate of corrosion resistance in three different concrete types: conventional cement concrete (CC), self-compacting concrete (SCC), and geopolymer concrete (GPC). To induce corrosion in the RC (RC) beams, an accelerated corrosion test setup was employed. The main objective of the study is to examine and compare the corrosion resistance of the RC beams by altering the concrete type, which were then exposed to accelerated corrosion to replicate the consequences of long-term exposure to corrosive environments. From the experimental studies it was found that the CC specimens possess a loss (load carrying capacity) of 31.28%, the SCC and GPC specimens possess a loss of 30.08% and 24.95%, respectively. This shows that GPC has higher resistance to salt solution when compared to SCC and CC specimens. Further all the three specimens show similar ductility index (DI), which was found to be in the range between 2.3 and 2.38 with a marginal variation of ± 0.1. GPC shows a 27.41% reduction in carbon emission compared to CC. On the other hand, SCC demonstrates a 12.30% reduction in carbon emission compared to CC. The investigation revealed that the total energy demand for producing 1 m3 of conventional concrete was measured to be 1.88 gigajoules (GJ/m3). On the other hand, the energy demand for the same volume of self-compacting concrete was slightly lower, specifically 1.78 GJ/m3. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, Balamurali AU - N, Anand AU - R, Samuvel raj AU - Andrushia, Diana AU - Lublóy, Éva Eszter TI - Practicability and environmental impact assessment of synthetic fibre reinforced polymer (SFRP) stirrups in reinforced concrete beams JF - HELIYON J2 - HELIYON VL - 10 PY - 2024 IS - 7 PG - 18 SN - 2405-8440 DO - 10.1016/j.heliyon.2024.e28149 UR - https://m2.mtmt.hu/api/publication/34771158 ID - 34771158 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Electronics and Communication Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, Hungary Export Date: 5 April 2024 Correspondence Address: Lubloy, E.; Department of Construction Materials and Technologies, Hungary; email: lubloy.eva@emk.bme.hu Correspondence Address: N, A.; Department of Civil Engineering, India; email: nanand@karunya.edu AB - In this study, the objective is to explore the practicability of incorporating synthetic fibre reinforced polymer (SFRP) stirrups into reinforced concrete beams. This investigation revolves around evaluating their effectiveness from two key perspectives: their structural performance and environmental impact. To accomplish this, four set of specimens were prepared, each integrating SFRP stirrups, and testing them under a rigorous three-point bending load test. The structural performance analysis entails a comprehensive examination on the critical design factors such as: the load-deflection relationship and the contribution these SFRP stirrups to improve the ductility performance, flexural stiffness, deformability factor, flexural toughness and energy absorption capacity. The findings of this study indicate that the SFRP stirrups exhibit commendable shear capacity, meeting the necessary requirements, and simultaneously demonstrate satisfactory ductility. It is determined, that the optimal design for these SFRP stirrups involves utilizing narrow and thin stirrups placed at relatively larger intervals. Furthermore, this research delves into assessing the environmental impact of incorporating SFRP stirrups. This assessment enables us to comprehensively evaluate the environmental implications of the entire life cycle of these stirrups in structural beam. Moreover, the analysis reveals that, SFRP stirrups yields lower environmental impacts compared to their steel counterparts, they still provide valuable insights into the overall sustainability considerations within the context of reinforced concrete structures. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Alvi, I.H. AU - Li, Q. AU - Hu, H. AU - Onyekwena, C.C. AU - Hou, Y. AU - Hakuzweyezu, T. AU - Iftikhar, Sahar AU - Chen, B. TI - A critical review of the advancements in acid-activated metakaolin geopolymers JF - CONSTRUCTION AND BUILDING MATERIALS J2 - CONSTR BUILD MATER VL - 421 PY - 2024 PG - 18 SN - 0950-0618 DO - 10.1016/j.conbuildmat.2024.135609 UR - https://m2.mtmt.hu/api/publication/34742504 ID - 34742504 N1 - State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China University of Chinese Academy of Sciences, Beijing, 100049, China Budapest University of Technology and Economics, Hungary Export Date: 18 March 2024 CODEN: CBUME Correspondence Address: Li, Q.Xiaohongshan 2, Wuchang, China; email: qli@whrsm.ac.cn Funding details: 2021CFA030 Funding details: 2021ZD0034 Funding details: Chinese Academy of Sciences, CAS Funding details: National Key Research and Development Program of China, NKRDPC, 2022YFE0115800 Funding details: Alliance of International Science Organizations, ANSO Funding text 1: This work was supported by the National Key R&D Program of China (Grant No. 2022YFE0115800 ), the Creative Groups of Natural Science Foundation of Hubei Province (Grant No. 2021CFA030 ), and the Major Project of Inner Mongolia Science and Technology (Grant No. 2021ZD0034 ). The authors would also like to acknowledge the support of the ANSO Scholarship for Young Talents in China for the Chinese Academy of Sciences . AB - Alternative to ordinary Portland cement (OPC), geopolymer binders emit low CO2 during manufacturing. Recently, acid-activated geopolymers were found to transform the mechanical performance of the binder. The review uses scientometric analysis to summarize the advancements in phosphoric acid-based metakaolin geopolymer (MGPacid). Web of Science (WOS) was used to retrieve relevant literature data. Science mapping and bibliometric viewpoint by CiteSpace presents: (1) the growth of the literature with the highest citations, (2) keyword analysis, (3) the contributing journals, (4) the most influential researchers, and (5) countries’ citation impact targeting the relative importance of the studied direction. Findings reflect the improvement in properties of geopolymer, including denser microstructure, mechanical strength, and evolution of reaction mechanism. Reaction kinetics of MGPacid were assessed under different factors of calcination temperature, type of precursor, acid molarities, molar mass ratios, and liquid/solid ratios exposed to various curing conditions. For assessment appraisal, the keyword occurrences (frequency analysis) were followed by the impact of influencing factors on the mechanical performance of the geopolymer. MGPacid was primarily used as a construction material, but areas of durability and its adoption in other applications need further investigation. MGPacid shows higher strength compared to alkali-activated geopolymer (MGPalkali). Various studies have conducted CO2 adsorption of MGPalkali after developing composites having activated carbon and zeolites. MGPalkali geopolymers showed better chemical stability than OPC under an acidic CO2 storage environment. As per authors' knowledge, the application of MGPacid in CO2 sequestration application is not made yet, particularly for enhanced oil and gas recovery (EOR and EGR) applications. Our findings suggest exploring alternative low-cost acid activators for geopolymers to develop an anti-CO2 corrosive binder to mitigate the well integrity issues of CO2 sequestration. © 2024 Elsevier Ltd LA - English DB - MTMT ER - TY - JOUR AU - Lublóy, Éva Eszter AU - Major, Zoltán TI - Alagútfalazatok termikus vizsgálata (4. rész) –Tartószerkezeti elemzés JF - SÍNEK VILÁGA J2 - SÍNEK VILÁGA VL - LXVI PY - 2024 IS - 1 SP - 11 EP - 23 PG - 13 SN - 0139-3618 UR - https://m2.mtmt.hu/api/publication/34729487 ID - 34729487 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Raj, R S. AU - Arulraj, G.P. AU - Anand, N. AU - Kanagaraj, B. AU - Lublóy, Éva Eszter TI - Influence of Nano-Fly Ash on mechanical properties, microstructure characteristics and sustainability analysis of Alkali Activated Concrete JF - DEVELOPMENTS IN THE BUILT ENVIRONMENT J2 - DEV BUILT ENVIRON VL - 17 PY - 2024 PG - 24 SN - 2666-1659 DO - 10.1016/j.dibe.2024.100352 UR - https://m2.mtmt.hu/api/publication/34726781 ID - 34726781 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Tamil Nadu, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., Budapest, H-1111, Hungary Export Date: 8 March 2024 Correspondence Address: Lubloy, E.; Department of Construction Materials and Technologies, Műegyetem rkp. 3., Hungary; email: lubloy.eva@emk.bme.hu Correspondence Address: Anand, N.; Department of Civil Engineering, Tamil Nadu, India; email: nananad@karunya.edu Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding text 1: The authors wish to acknowledge the Science and Engineering Research Board , Department of Science and Technology of the Indian Government for the financial support ( YSS/2015/001196/ES ) provided for carrying out this research. The research reported in this paper is part of project no. BME-NVA-02, implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund , financed under the TKP2021 funding scheme. AB - Ordinary Portland Cement (OPC) composites significantly affect the atmosphere by emitting Carbon dioxide (CO2) during its production process. The addition of Nano Materials (NM) for the construction could change the matrix configuration at the nano level. Compared to other NMs, converting industrial by-products and locally available materials into nano size can enhance the characteristics of the binder composites. This research work focuses on the effects of Nano Fly ash (nFA), on the fresh, mechanical, microstructural, and thermal resistance properties of Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS) based Alkaline Activator Nano Concrete (AANC). The impact of adding nFA in various concentrations of 3 %, 6 %, 9 %, 12 %, and 15 % on the properties of AANC was studied. By adding nFA in an optimal proportion, the degree of geo-polymerization is improved which is found by Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Energy Dispersive X-Ray Analysis (EDAX) and Fourier Transform Infrared (FTIR). Results indicate that the addition of nFA significantly increased polymerization, reducing initial and final setting times by 13.3 %–52.5 % and 5.3 %–28.8 %, respectively. Moreover, nFA promoted the formation of polymer gel, leading to a denser microstructure with fewer cracks and refined pores, resulting in a substantial increase in mechanical strength, particularly with 9% nFA, achieving an optimal CS of 56.14 MPa after 28 days which is 37.97 % improvement compared to the mix without nFA. However, when nFA was added, beyond 9 %, the performances declined due to its high surface area resulting in a non-uniform dispersion that promoted agglomeration. This dispersion enhances the formation of C-A-S-H and C–S–H gels. The addition of nFA in AANC can be an environmentally friendly solution by reducing CO2 emissions, energy consumption, cost reduction and increased sustainability. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, B. AU - Anand, N. AU - Raj, R S. AU - Lublóy, Éva Eszter TI - Utilizing agricultural turmeric bulbs as an alternative to traditional coarse aggregates in geopolymer concrete to explore its engineering properties JF - DEVELOPMENTS IN THE BUILT ENVIRONMENT J2 - DEV BUILT ENVIRON VL - 17 PY - 2024 PG - 19 SN - 2666-1659 DO - 10.1016/j.dibe.2024.100358 UR - https://m2.mtmt.hu/api/publication/34726779 ID - 34726779 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Tamil Nadu, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3., Budapest, H-1111, Hungary Export Date: 8 March 2024 Correspondence Address: Lubloy, E.; Department of Civil Engineering, Tamil Nadu, India; email: lubloy.eva@emk.bme.hu Correspondence Address: Anand, N.; Department of Civil Engineering, Tamil Nadu, India; email: nananad@karunya.edu Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding text 1: The authors wish to acknowledge the Science and Engineering Research Board , Department of Science and Technology of the Indian Government for the financial support ( YSS/2015/001196/ES ) provided for carrying out this research. The research reported in this paper is part of project no. BME-NVA-02, implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research , Development and Innovation Fund , financed under the TKP2021 funding scheme. AB - Extensive infrastructure development has led to the overexploitation of traditional virgin materials. To preserve the ecosystem, it's crucial to find alternatives. This study explores the viability of using turmeric bulb (TB) as a substitute for virgin coarse aggregate in geopolymer concrete (GPC). With 36 trial mixes varying in activator concentration and curing methods, the aim is to assess TB as a filler material replacement. Experimental trials revealed that replacing up to 20% of the coarse aggregate with TB maintained 28-day compressive strength at 35–38 MPa under ambient curing. However, with oven curing, strength was sustained only up to a 30% TB replacement, beyond which it declined. The UPV value for concrete with 50% TB was 3.79–3.9 km/s. Increasing the activator concentration from 8 M to 16 M significantly enhanced GPC strength, ranging between 24 and 36 MPa. GPC blended with TB showed a higher rate of water absorption, ranging from 24% to 26% for 50% replacement of conventional coarse aggregate. Sustainability analysis revealed that lower activator concentrations (e.g., 8 M) offered a more sustainable alternative to traditional cement concrete. In conclusion, this study underscores the potential of replacing coarse aggregate in GPC, promoting eco-friendly concrete production through sustainable practices and optimized activator concentration. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, B. AU - Anand, N. AU - Raj, R S. AU - Jerry, R. AU - Lukose, J. AU - Lublóy, Éva Eszter TI - Influence of coatings on residual strength of geopolymer concrete columns subjected to fire exposure: An experimental investigation JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - 20 PY - 2024 PG - 19 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e02990 UR - https://m2.mtmt.hu/api/publication/34726777 ID - 34726777 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, 1521, Hungary Export Date: 8 March 2024 Correspondence Address: Anand, N.; Department of Civil Engineering, India; email: davids1612@gmail.com Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding text 1: The authors wish to acknowledge the Science and Engineering Research Board, Department of Science and Technology of the Indian Government for the financial support ( YSS/2015/001196/ES ) provided for carrying out this research. The research reported in this paper is part of project no. BME-NVA-02, implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund , financed under the TKP2021 funding scheme. AB - Fires occurring within buildings present a grave concern, as they entail substantial risks to human lives, property, and the environment. Implementing appropriate fire safety measures becomes imperative to mitigate the occurrence of fires and ensure efficient response in the event of an incident. The primary aim of the study is to examine the performance of various coatings on the residual strengths of the reinforced normal strength self-compacting geopolymer concrete (NSGC) and high strength self-compacting geopolymer concrete (HSGC) columns subjected to standard temperature exposure in accordance with ISO 834 guidelines. The design compressive strength of the concretes was 36.12, 57.06 and 52.8 MPa. Two types of coating were employed in the present investigation namely ceramic wool wrapping and high alumina cement. A computerized electric furnace is used to heat the column specimens. Amongst the forty-two columns developed, six specimens tested without temperature exposure and protective coating as a reference specimen. Twelve specimens were heated as per ISO fire curve and tested to assess the residual axial strength performance and twenty-four specimens were coated with protective layers, then heated and tested to assess the post fire performance. It is exemplified that the composite protective coating offers effective resistance to concrete, gaining optimum axial strength performance. The findings show that these fire protecting composites have a high potential for utilizing as new strengthening techniques for reinforced concrete (RC) columns. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Major, Zoltán AU - Bodnár, László AU - Merczel, Dániel Balázs AU - Szép, János AU - Lublóy, Éva Eszter TI - Analysis of the Heating of Steel Structures During Fire Load JF - EMERGING SCIENCE JOURNAL J2 - EMERG SCI J VL - 8 PY - 2024 IS - 1 SP - 1 EP - 16 PG - 16 SN - 2610-9182 DO - 10.28991/ESJ-2024-08-01-01 UR - https://m2.mtmt.hu/api/publication/34683827 ID - 34683827 N1 - Export Date: 8 March 2024 Correspondence Address: Lublóy, É.; Department of Construction Materials and Technologies, Hungary; email: lubloy.eva@emk.bme.hu Funding details: Széchenyi István Egyetem, SZE Funding text 1: This article was supported by István Széchenyi University (*\\Ę). U AB - During the preparation of our article, we present in detail the changes in the thermotechnical parameters of carbon steel and corrosion resistance during fire. After that, we present in detail the calculation of the heating of steel structures without fire protection. We feel this is important because it is not possible to provide stainless steel with fire protection for aesthetic reasons, and it is also not typical for thin-walled galvanized structures. We also present the calculation of structures with fire protection in detail and present the background for editing commonly used nomograms. Such a nomogram is also available in the literature, but it can be considered true with significant simplifications. During the practical planning, the applied fire protection regulations were highly standardized. Realizing that there is no design nomogram for these types of solutions, we created and published them in our article. The advantage of these is that the applicable design can also be found as the optimum of the designs considered to be potentially good. With this solution, we can save time during planning, and we can also get a more cost-effective solution for the fire protection cover. The advantage of the presented method is that, if required, the editing of the nomograms can be extended to other designs by knowing the material characteristics and the layer thickness. Another option of the presented method is that the solution can also be applied to special fire loads, and nomograms can be produced for them as well (e.g., hydrocarbon fires). Doi: 10.28991/ESJ-2024-08-01-01 Full Text: PDF LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, Balamurali AU - Anand, N. AU - Raj, Samuvel AU - Lublóy, Éva Eszter TI - Advancements and environmental considerations in portland cement-based radiation shielding concrete: Materials, properties, and applications in nuclear power plants– review JF - CLEANER ENGINEERING AND TECHNOLOGY J2 - CLEANER ENGINEERING AND TECHNOLOGY VL - 19 PY - 2024 PG - 15 SN - 2666-7908 DO - 10.1016/j.clet.2024.100733 UR - https://m2.mtmt.hu/api/publication/34682436 ID - 34682436 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, 1521, Hungary Export Date: 18 March 2024 Correspondence Address: Lubloy, E.; Department of Construction Materials and Technologies, Hungary; email: lubloy.eva@epito.bme.hu Correspondence Address: Anand, N.; Department of Civil Engineering, India; email: nanand@karunya.edu Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding text 1: The authors wish to acknowledge the Science and Engineering Research Board , Department of Science and Technology of the Indian Government for the financial support ( YSS/2015/001196/ES ) provided for carrying out this research. The research reported in this paper is part of project no. BME-NVA-02, implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development and Innovation Fund , financed under the TKP2021 funding scheme. LA - English DB - MTMT ER -