Theoretical and Numerical Analysis of an Aluminum Foam Sandwich Structure

Alaa Al-Fatlawi; Károly Jármai; György Kovács

doi:10.1556/606.2020.15.3.11

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Pollack Periodica

Volume/Issue:: Volume 15: Issue 3

Theoretical and Numerical Analysis of an Aluminum Foam Sandwich Structure

Authors:

Alaa Al-Fatlawi

Alaa Al-Fatlawi Faculty of Mechanical Engineering and Informatics, University of Miskolc H-3515 Miskolc, Egyetemváros, Hungary

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vegyalaa@uni-miskolc.hu

Károly Jármai

Károly Jármai Faculty of Mechanical Engineering and Informatics, University of Miskolc H-3515 Miskolc, Egyetemváros, Hungary

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jarmai@uni-miskolc.hu

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György Kovács

György Kovács Faculty of Mechanical Engineering and Informatics, University of Miskolc H-3515 Miskolc, Egyetemváros, Hungary

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altkovac@uni-miskolc.hu

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Pages:: 113–124

Online Publication Date:: 07 Nov 2020

Publication Date:: 07 Nov 2020

Article Category:: Research Article

DOI:: https://doi.org/10.1556/606.2020.15.3.11

Keywords:: Sandwich structure; Fiber reinforced plastic face-sheet; Aluminum foam core; Structural optimization; Minimum weight

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The aim of the research was to develop a new lightweight sandwich structure, which can be used for elements of air containers. The structure consists of aluminum foam core with fiber reinforced composite face-sheets. Nine different laminated glass or/and carbon fiber reinforced plastic face-sheet combinations were investigated. Finite element analysis of the sandwich structures was introduced. Single-objective optimization of the new sandwich structure was achieved for minimal weight. Five design constraints were considered: stiffness of the structure, face-sheet failure, core shear, face-sheet wrinkling, size constraints for design variables. The elaborated composite structure results significant weight savings due to low density.

Abstract

1 Introduction

The purpose of the study is the design of a lightweight structure consists of fiber reinforced plastic face-sheets (nine different laminated glass fiber or/and carbon fiber reinforced plastic face-sheet combinations) and aluminum foam core. The fiber reinforced plastic face-sheets and the core has a small density and high specific stiffness, which can meet the stiffness requirements and reduce the weight of the sandwich structure. The elaborated structural model can be used for manufacturing of walls, floor and roof of containers to fulfill the requirements of shipping and airlines carriers. The aim of the application of lightweight containers is to provide a huge savings in weight compared to conventional steel containers, which results in lower fuel consumption of transport vehicles and less environmental damage.

The sandwich structures consist of composite face-sheets and foam core are widely utilized in many engineering applications such as aerospace and automotive applications due to its high performance like bending stiffness and strength to weight ratios [1]. Huang and Alspaugh [2] introduced a method to determine the minimum weight of sandwich beams. The most common applied design constraints related to bending stress, shear stress and deflection, where the face-sheets thickness and the core thickness are design variables. Gibson [3] described an analytical method to find the optimum thickness and density of the foam core sandwich beam to minimize the weight. Gibson and Triantafillou described the way to minimize the weight of a sandwich beam with a foam core. The analysis gave the optimum core and face-sheets thicknesses and the density of the core [4]. In the books of Zenkert and Bitzer several methods and algorithms are described to minimize the weight of sandwich structures with symmetrical and unsymmetrical face-sheets and subjected to bending and torsional stiffness requirement [5]-[6]. Kota and Jarmai show also a very well scalable discrete firefly algorithm. The built in general reduced gradient and evolutionary algorithms of the Excel solver are also compared solving similar problems [7]. Hazim and Jarmai estimate the minimum structural dimensions of robot arms [8]. Many researchers have studied the influence of hybrid composite materials on mechanical properties of the structure [9]. Dong and Davies studied the flexural behavior of hybrid composites consist of glass and carbon fibers [10]. The effect of hybrid observed when the natural fiber reinforced plastics layers built into the conventional sandwich panels with aluminum face-sheets [11]. Lot of algorithms is available for optimization of composite laminated structures [12]. A few studies included the cost of the sandwich structure as a design aim [13].

2 A new sandwich structural model

The newly constructed sandwich structure consists of aluminum (Al) foam core with laminated glass fiber and/or carbon fiber reinforced plastic face-sheets, see Fig. 1. The dimensions and weights of the core and face-sheets used in this structure are given in Table I. The technical notes of the flexure model program for symmetrical sandwich structures were clarified. The norm of the model is MIL-STD-401B [14].

Fig. 1

Aluminum foam core sandwich structure with laminated composite face-sheets

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

Table I

Data relating to the structural elements of the investigated sandwich structure

Fibers	Dimension					Density			Weight
Fibers	l	b	ℎ	t_c	t_f	p_c	p_g	p_cr	w_core	w_skin	wt
Unit	mm	mm	mm	mm	mm	kg/m³	kg/m³	kg/m³	kg	kg	kg
E-glass	1000	100	24	20	2	300			0.6	0.38	1.36
Carbon	1000	100	24	20	2	300	1900	1600	0.6	0.32	1.24
Hybrid	1000	100	24	20	2	300			0.6	0.35	1.30

where l is the length;b is the width of the sandwich structure; &Jai_unknown_entity_euclidsymbol_F072;_g is the density of the E-glass fiber/epoxy resin laminate; is the density of the carbon fiber/epoxy resin laminate; &Jai_unknown_entity_euclidsymbol_F072;_cr is the density of the foam core; t_f is the thickness of the face-sheet; t_c is the thickness of the foam core and ℎ is the total thickness of the sandwich structure. W_core is the weight of the foam core; is the weight of the face-sheet;W_t is the total weight of the sandwich structure.

2.1 Aluminum foam core

The foam core is closed cell formed from Al alloy. The mechanical properties of the core make it ideal for several applications. These properties include high strength and stiffness to weight ratio and high energy absorption as shown in Table II, [15].

Table II

Data of Cymat A35620SC 030SS stabilized aluminum foam

E	Compressive modulus	1200	MPa
υ	Poission's ratio	0.33	----
G	Shear modulus	1000	MPa
σ	Compressive strength	4	MPa
τ	Shear strength	1	MPa
&Jai_unknown_entity_euclidsymbol_F072;	Density	300	kg/m³

2.2 Laminated fiber reinforced plastic face-sheets

Nine different sandwich constructions were studied, which consist of Al foam core with upper and lower skin face-sheets. The laminated glass fiber and/or carbon fiber reinforced plastic face-sheets were symmetrical concerning to the mid-plane of the sandwich structure. Every skin face-sheet composed of 4-layers. The fiber orientation in the face-sheets is having cross ply (0°, 90°) and angle ply ±45°. Table III includes the mechanical properties of the different composite layers.

Table III

Mechanical properties of composite materials [16]

Fiber 0°, 90° fabric to loading axis, Dry, Room Temperature, Vf = 50%
Property Young’s Modulus 0° Young’s Modulus 90° In-plane Shear Modulus Major Poisson’s Ratio Ultimate Tensile Strength 0° Ultimate Compression Strength 0° Ultimate Tensile Strength 90° Ultimate Compression Strength 90° Ultimate In-plane Shear Strength	Symbol E₁ E₂ G₁₂ V₁₂ X_t X_c Y_t Y_c S	E-glass 25 25 4 0.2 440 425 440 425 40	Carbon 70 70 5 0.1 600 570 600 570 90	Units GPa GPa GPa ----MPa MPa MPa MPa MPa
Fiber ±45° to loading axis, Dry, Room Temperature, Vf = 50% (fabric)
Property Longitudinal Modulus Transverse Modulus In-plane Shear Modulus Poisson’s Ratio Tensile Strength Compression Strength In-plane Shear Strength	Symbol E₁ E₂ G₁₂ V₁₂ X_t X_c S	E-glass 12.2 12.2 8 0.53 120 120 150	Carbon 19.1 19.1 30 0.74 120 120 310	Units GPa GPa GPa ----MPa MPa MPa

E-glass fiber/epoxy resin face-sheets

Three constructions were investigated: Al foam core sandwich structure with 4-layers in the upper and 4-layers in the lower skin face-sheets made of fabric of E-glass fiber/epoxy resin with fiber orientation (0°, 90°, 0°, 90°), (0°, 90°, +45°, –45°) and (+45°, –45°, +45°, –45°).

Carbon fiber/epoxy resin face-sheets

Three constructions were investigated: Al foam core sandwich structure with 4-layers in the upper and 4-layers in the lower skin face-sheets made of fabric of carbon fiber/epoxy resin with fiber orientation (0°, 90°, 0°, 90°), (0°, 90°, +45°, –45°) and (+45°, –45°, +45°, –45°).

Hybrid face-sheets (combination of glass and carbon fiber layers)

Three constructions were investigated: Al foam core sandwich structure with 4-layers in the upper and 4-layers in the lower skin face-sheets (outer two layers of carbon and inner two layers of E-glass laminas). The hybrid face-sheet is the combination of carbon fiber and E-glass fiber/epoxy resin laminas with different fiber orientations: (0°, 90°, 0°, 90°), (0°, 90°, +45°, –45°) and (+45°, –45°, +45°, –45°).

3 Finite element analysis of the investigated sandwich structures

In this study, the deflection, skin stress and core shear stress were calculated numerically by using finite element analysis (Digimat-HC) program for 4-point flexural model, where is the applied load; is the deflection of sandwich structure; is the skin stress and is the core shear stress. Numerical results of the finite element analysis can be seen in (Table IV- Table VI); and in (Fig. 2- Fig. 4). The introduction of print screens of the finite element analysis results for all of nine constructions is not possible in this study due to space constraints.

Table IV

Analytical and numerical results for aluminum foam core sandwich structure with E-glass fiber/epoxy resin face-sheets with different fiber orientations (0°, 90° and ±45°)

E-glass fiber	Numerical results				Optimum results			W_t	W_red
Symbol	p	&Jai_unknown_entity_euclidsymbol_F064;	σ_skin	τ_core	t_{c opt}	t_{f opt}	W_min	W_t	W_red
Unit	N	mm	MPa	MPa	mm	mm	kg	kg	%
0°, 90°, 0°, 90°	1000	9.877	25.6	1.08	23.224	0.998	1.076	1.36	20.88
0°, 90°, ±45°	1000	10.949	28.4	1.18	23.244	1.012	1.081	1.36	20.51
±45°, ±45°	1000	12.597	25.1	1.36	23.224	0.984	1.070	1.36	21.32

Table V

Analytical and numerical results for aluminum foam core sandwich structure with carbon fiber/epoxy resin face-sheets with different fiber orientations (0°, 90° and ±45°)

E-glass fiber	Numerical results				Optimum results			W_t	W_red
Symbol	p	&Jai_unknown_entity_euclidsymbol_F064;	σ_skin	τ_core	t_{c opt}	t_{f opt}	W_min	W_t	W_red
Unit	N	mm	MPa	MPa	mm	mm	kg	kg	%
0°, 90°, 0°, 90°	1000	3.746	26.6	0.54	21.204	1.110	0.991	1.24	20.08
0°, 90°, ±45°	1000	4.281	29.3	0.57	21.204	0.998	0.955	1.24	22.98
±45°, ±45°	1000	5.502	26.4	0.67	19.183	0.970	0.886	1.24	28.54

Table VI

Analytical and numerical results for aluminum foam core sandwich structure with hybrid face-sheets with different fiber orientations (0°, 90° and ±45°)

E-glass fiber	Numerical results				Optimum results			W_t	W_red
Symbol	p	&Jai_unknown_entity_euclidsymbol_F064;	σ_skin	τ_core	t_{c opt}	t_{f opt}	W_min	W_t	W_red
Unit	N	mm	MPa	MPa	mm	mm	kg	kg	%
0°, 90°,0°, 90°	1000	5.185	37.6	0.66	23.224	. 1.181	1.110	1.30	14.61
0°, 90°, ±45°	1000	5.461	39.6	0.68	23.224	1.279	1.144	1.30	12.00
±45°, ±45°	1000	9.708	30.9	1.07	23.224	1.096	1.080	1.30	16.92

Fig. 2

Numerical results by using (Digimat-HC) program; flexural model of the sandwich structure consists of E-glass fiber/epoxy resin face-sheets (0°, 90°, 0°, 90°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

Fig. 3

Numerical results by using (Digimat-HC) program; flexural model of the sandwich structure consists of carbon fiber/epoxy resin face-sheets (±45°, ±45°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

Fig. 4

Numerical results by using (Digimat-HC) program; flexural model of the sandwich structure consists of hybrid face-sheets (0°, 90°, +45°, –45°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

4 Minimum weight optimization of the investigated sandwich structure

The optimization method for the newly constructed sandwich structure (Fig. 1) was elaborated. The fibers orientation in the face-sheets is having angles of cross ply 0°, 90° and angle ply ±45°. The optimal design variables were face-sheet thickness and core thickness to minimize the weight of the sandwich structures, Eqs. (1)-(3). During the optimization five design constraints were taken into consideration, Eqs. (4)-(8). The equations of the optimization problem are listed below [17]. The classical lamination theory and Tsai-Hill criteria of the first ply failure used to calculate the mechanical properties of the laminated face-sheet [18]. The constraints of the optimization problem are stiffness, face-sheet failure, core shear, face-sheet wrinkling.

The sandwich structure stiffness, the maximum load of face-sheet failure, core shear and skin wrinkling for every core thickness and face-sheet thickness were calculated. With all these data, for every step, the minimum face-sheet thickness was calculated that accomplishes the load defined and the stiffness required, Eq. (4). The software calculates the minimum weight condition for the sandwich structure, which corresponds to the face-sheet thickness and the core thickness. This software is a modified version of the software in the composite sandwich optimizer 2017, GitHub, Inc [19]. The program was developed to fit with the flexure model. The results of numerical (Digimat-HC) program were used as inputs to achieve the desired results (maximum deformation _"#$ and maximum load p_max).

4.1 Total weight objective functions

Weight of E-glass fiber/epoxy resin face-sheets with aluminum foam core:

W_{t} = W_{f} + W_{c} = 2 W_{g} + W_{c} = 2 p_{g} t_{g} l b + p_{c} t_{c} l (1)

Weight of carbon fiber/epoxy resin face-sheets with aluminum foam core:

W_{t} = W_{f} + W_{c} = 2 W_{c r} + W_{c} = 2 p_{c r} t_{c r} l b + p_{c} t_{c} l b . (2)

Weight of hybrid face-sheets with aluminum foam core:

W_{t} = W_{f} + W_{c} = 2 (W_{g} + W_{c r}) + W_{c} = 2 (p_{g} t_{g} l b + p_{c r} t_{c r} l b) + p_{c} t_{c} l b . (3)

4.2 Design constraint

Constraint for the stiffness of the sandwich structure:

The minimum stiffness of sandwich structure * +,_" was calculated by using given data from and numerical results (Digimat-HC) ( and ).

{(E I)}_{\min} = \frac{p l^{3}}{B_{3} δ} \leq D = \frac{E_{f} t_{f} h^{2} b}{2}, {h=t}_{c} + t_{f} .  (4)

Constraint for face-sheets failure

P_{a c t} \leq P_{f f} = \frac{σ_{f} b t_{f} h}{B_{1} l} (5)

Constraint for core shear

P_{a c t} \leq P_{c s} = \frac{τ_{c} b h}{B_{2}} (6)

Constraint for face-sheet wrinkling

P_{a c t} \leq P_{w r} = \frac{b t_{f} h}{2 B_{1} l {(E_{c} G_{c} E_{f})}^{1 / 3}} (7)

Size constraint for design variables

10 m m \leq t_{c} o p t \leq 100 m m, and 0 .1mm \leq t_{f}_{o p t} \leq 5 m m, (8)

Where $B_{1} = \frac{1}{8}, B_{2} = \frac{1}{2}, B_{3} = \frac{768}{11},$ and P_act=1000 N (Simply supported, flexural model).

4.3 Results of the optimization

The final results are optimum core thickness ( ! ), optimum face thickness ( ! ) and minimum weight ( _" ) as shown in (Table IV- Table VI) and (Fig. 5- Fig. 7). The optimization results of all 9 constructions are not possible in this study due to space constraints.

Fig. 5

Theoretical results by using MATLAB program, flexure model, the sandwich structure consists of E-glass fiber/epoxy resin face-sheets (0°, 90°, 0°, 90°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

Fig. 6

Theoretical results by using MATLAB program, flexure model, the sandwich structure consists of carbon fiber/epoxy resin face-sheets (+45°, –45°, +45°, –45°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

Fig. 7

Theoretical results by using MATLAB program, flexure model, the sandwich structure consist of hybrid face-sheets (0°, 90°, +45°, –45°) with Al foam core

Citation: Pollack Periodica 15, 3; 10.1556/606.2020.15.3.11

5 Evaluation of the results

5.1 Numerical results in case of different types of laminated composite face-sheets

According to the numerical results of sandwich structures with aluminum foam core and different types of composite face-sheets, as shown in (Table IV- Table VI) and (Fig. 2- Fig. 4), the deflection and core shear stress of the sandwich structures with carbon fiber/epoxy resin face-sheet are less than the deflection and core shear stress of the sandwich structures with hybrid and E-glass fiber/epoxy resin face-sheet respectively, because of the carbon fiber having higher stiffness-to-weight ratio compared to E-glass fiber. The skin stress of the sandwich structures with E-glass fiber/epoxy resin face-sheet is less than the skin stress of the sandwich structures with carbon fiber/epoxy resin and hybrid face-sheet respectively, because of the E-glass fiber having high strength-to-weight ratio and more flexible compared to carbon fiber.

5.2 Numerical results in case of different fiber orientations of composite layers

The numerical results of sandwich structures with aluminum foam core and different fiber orientations of composite face-sheets cross ply (0°, 90°) and angle ply (±45°) are the following: the deflection and core shear stress of the sandwich structures with face-sheet fiber orientation (0°, 90°, 0°, 90°) are less than the deflection and core shear stress of the sandwich structures with face-sheets fiber orientation (0°, 90°, +45°, –45°) and fiber orientation (+45°, –45°, +45°, –45°) respectively, because of the fiber with cross ply orientation (0°, 90°, 0°, 90°) having higher young modulus of elasticity and stiffness compare with angle ply (+45°, –45°, +45°, –45°). The skin stress of the sandwich structures with fiber orientation (+45°, –45°, +45°, –45°) of face-sheet are less than the skin stress of the sandwich structures with fiber orientation (0°, 90°, 0°, 90°) and fiber orientation (0°, 90°, +45°, –45°).

5.3 Theoretical results in case of different types of laminated composite face-sheets

According to the theoretical results, as shown in (Table IV- Table VI) and (Fig. 5-Fig. 7), the weight of the sandwich structures with carbon fiber/epoxy resin face-sheet is smaller than the weight of the sandwich structures with E-glass fiber/epoxy resin and hybrid of face-sheets.

5.4 Theoretical results in case of different fiber orientations of composite layers

According to the theoretical results of sandwich structures with aluminum foam core and different fiber orientation of composite materials face-sheet cross ply (0°, 90°) and angle ply ±45°, the weight of the sandwich structure with fiber orientation (+45°, –45°, +45°, –45°) of face-sheet is less than the weight of the sandwich structures with fiber orientation (0°, 90°, 0°, 90°) and fiber orientation (0°, 90°, +45°, –45°).

6 Conclusions

The aim of the study was to develop a new sandwich structure, which can be used for manufacturing of walls, floor and roof of lightweight containers. The aim of the application of lightweight containers is to provide significant weight savings compared to conventional steel containers, which results in lower fuel consumption of transport vehicles and less environmental damage.

The new sandwich structure consists of aluminum foam core with upper and lower composite face-sheets. Nine different laminated glass fiber or/and carbon fiber reinforced plastic face-sheet combinations were investigated. In the study the finite element analysis of the investigated sandwich structures was introduced.

The optimization method was also elaborated for the new sandwich structure. The objective function was the total weight of the structure and five design constraints were taken into consideration, which were the following: total stiffness of the structure; face-sheet failure; core shear; face-sheet wrinkling and size constraint for design variables.

Single-objective optimization of the new sandwich structural model was achieved for minimal weight. In the case study the optimal structure, which ensures the minimal weight of the sandwich structure is a carbon fiber/epoxy laminated face-sheet with 4 layers, with fiber orientation (+45°, –45°, +45°, –45°) and Al foam core, which thickness is 19.183 mm. This optimal Al foam sandwich structure provides 28.54% weight saving compared to the original structure.

It can be concluded based on the results of the research, that the application of the elaborated sandwich structure can be suggested in those applications where weight saving is the most important design aim.

Acknowledgements

The described article was carried out as part of the EFOP-3.6.1-16-2016-00011 ‘Younger and Renewing University - Innovative Knowledge City - institutional development of the University of Miskolc aiming at intelligent specialization’ project implemented in the framework of the Szechenyi 2020 program. The realization of this project is supported by the European Union, co-financed by the European Social Fund.

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Pollack Periodica

Print ISSN:: 1788-1994

Online ISSN:: 1788-3911

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Bálint BACHMANN (Institute of Architecture, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Jeno BALOGH (Department of Civil Engineering Technology, Metropolitan State University of Denver, Denver, Colorado, USA)
Magdaléna BÁLINTOVÁ (Institute of Environmental Engineering, Faculty of Civil Engineering, Technical University of Kosice. Kosice, Slovakia)
Radu BANCILA (Department of Geotechnical Engineering and Terrestrial Communications Ways, Faculty of Civil Engineering and Architecture, “Politehnica” University Timisoara, Romania)
Charalambos C. BANIOTOPULOUS (Department of Civil Engineering, Chair of Sustainable Energy Systems, Director of Resilience Centre, School of Engineering, University of Birmingham, U.K.)
Oszkar BIRO (Graz University of Technology, Institute of Fundamentals and Theory in Electrical Engineering, Austria)
Ágnes BORSOS (Institute of Architecture, Department of Interior, Applied and Creative Design, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Matteo BRUGGI (Dipartimento di Ingegneria Civile e Ambientale, Politecnico di Milano, Italy)
Petra BUJŇÁKOVÁ (Department of Structures and Bridges, Faculty of Civil Engineering, University of Žilina, Slovakia)
Anikó Borbála CSÉBFALVI (Department of Civil Engineering, Institute of Smart Technology and Engineering, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Mirjana S. DEVETAKOVIĆ (Faculty of Architecture, University of Belgrade, Serbia)
Adriana EŠTOKOVA (Institute of Environmental Engineering, Faculty of Civil Engineering, Technical University of Kosice. Kosice, Slovakia
Fabrizio FINUCCI (Dipartimento di Architettura Università Degli Studi Roma Tre, Roma, Italy)
Szabolcs FISCHER (Department of Transport Infrastructure and Water Resources Engineering, Faculty of Architerture, Civil Engineering and Transport Sciences Széchenyi István University, Győr, Hungary)
Radomir FOLIC (Department of Civil Engineering, Faculty of Technical Sciences, University of Novi Sad Serbia)
Jana FRANKOVSKÁ (Department of Geotechnics, Faculty of Civil Engineering, Slovak University of Technology in Bratislava, Slovakia)
Elena HELEREA (Dept. of Electrical Engineering and Applied Physics, Faculty of Electrical Engineering and Computer Science, Transilvania University of Brasov, Romania)
Ákos HUTTER (Department of Architecture and Urban Planning, Institute of Architecture, Faculty of Engineering and Information Technolgy, University of Pécs, Hungary)
Károly JÁRMAI (Institute of Energy and Chemical Machinery, Faculty of Mechanical Engineering and Informatics, University of Miskolc, Hungary)
Teuta JASHARI-KAJTAZI (Department of Architecture, Faculty of Civil Engineering and Architecture, University of Prishtina, Kosovo)
Xue KANG (Faculty of Architecture and Environmental Arts, Sichuan Fine Arts Institute, Chongqing, China)
Róbert KERSNER (Department of Technical Informatics, Institute of Information and Electrical Technology, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Rita KISS (Biomechanical Cooperation Center, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Budapest, Hungary)
István KISTELEGDI (Department of Simulation Design, Institute of Architecture, Ybl Miklós Faculty of Architecture and Civil Engineering, Óbuda University, Budapest, Hungary)
Imre KOCSIS (Department of Basic Engineering Research, Faculty of Engineering, University of Debrecen, Hungary)
László T. KÓCZY (Department of Information Sciences, Faculty of Mechanical Engineering, Informatics and Electrical Engineering, University of Győr, Hungary)
Dražan KOZAK (Faculty of Mechanical Engineering, University of Slavonski Brod, Slavonski Brod, Croatia)
Balázs Géza KÖVESDI (Department of Structural Engineering, Faculty of Civil Engineering, Budapest University of Engineering and Economics, Budapest, Hungary)
Tomáš KREJČÍ (Department of Mechanics, Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic)
Jaroslav KRUIS (Department of Mechanics, Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic)
Miklós KUCZMANN (Department of Automations, Faculty of Mechanical Engineering, Informatics and Electrical Engineering, Széchenyi István University, Győr, Hungary)
Maria Jesus LAMELA-REY (Departamento de Construcción e Ingeniería de Fabricación, University of Oviedo, Spain)
János LÓGÓ (Department of Structural Mechanics, Faculty of Civil Engineering, Budapest University of Technology and Economics, Hungary)
Frédéric MAGOULÉS (Department of Mathematics and Informatics for Complex Systems, Centrale Supélec, Université Paris Saclay, France)
Gabriella MEDVEGY (Department of Interior, Applied and Creative Design, Institute of Architecture, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Barhm Abdullah MOHAMAD (Department of Petroleum, Control and Operation, Koya Technical Institute, Erbil Polytechnic University, Kurdistan Region, Iraq)
Tamás MOLNÁR (Department of Visual Studies, Institute of Architecture, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Rad Majid MOVAHEDI (Department of Structural Engineering and Geotechnics, Faculty of Architecture Civil Engineering and Transport Sciences, Széchenyi István University, Győr, Hungary
Ferenc ORBÁN (Department of Mechanical Engineering, Institute of Smart Technology and Engineering, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Zoltán ORBÁN (Department of Civil Engineering, Institute of Smart Technology and Engineering, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Dmitrii RACHINSKIY (Department of Mathematical Sciences, The University of Texas at Dallas, Texas, USA)
Chro RADHA (Chro Ali Hamaradha) (Sulaimani Polytechnic University, Technical College of Engineering, Department of City Planning, Kurdistan Region, Iraq)
Maurizio REPETTO (Department of Energy “Galileo Ferraris”, Politecnico di Torino, Italy)
Olena SAVCHENKO (Department of Heat and Gas Supply and Ventilation, Institute of Civil Engineering and Building Systems, Lviv Polytechnic National University, Lviv, Ukraine)
Zoltán SÁRI (Department of Technical Informatics, Institute of Information and Electrical Technology, Faculty of Engineering and Information Technology, University of Pécs, Hungary)
Grzegorz SIERPIŃSKI (Department of Transport Systems and Traffic Engineering, Faculty of Transport, Silesian University of Technology, Katowice, Poland)
Zoltán SIMÉNFALVI (Institute of Energy and Chemical Machinery, Faculty of Mechanical Engineering and Informatics, University of Miskolc, Hungary)
Andrej ŠOLTÉSZ (Department of Hydrology, Faculty of Civil Engineering, Slovak University of Technology in Bratislava, Slovakia)
Hussein Kareem SULTAN (Department of Civil Engineering, College of Engineering, Al-Muthanna University, Samawa, Iraq)
Zsolt SZABÓ (Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Hungary)
Mykola SYSYN (Chair of Planning and Design of Railway Infrastructure, Institute of Railway Systems and Public Transport, Technical University of Dresden, Germany)
Barry H. V. TOPPING (Heriot-Watt University, UK, Faculty of Engineering and Information Technology, University of Pécs, Hungary)

POLLACK PERIODICA
Pollack Mihály Faculty of Engineering
Institute: University of Pécs
Address: Boszorkány utca 2. H–7624 Pécs, Hungary
Phone/Fax: (36 72) 503 650

E-mail: peter.ivanyi@mik.pte.hu

or amalia.ivanyi@mik.pte.hu

Indexing and Abstracting Services:

SCOPUS
CABELLS Journalytics

2024
Scopus
CiteScore
CiteScore rank
SNIP
Scimago
SJR index	0.385
SJR Q rank	Q3

2023
Scopus
CiteScore	1.5
CiteScore rank	Q3 (Civil and Structural Engineering)
SNIP	0.849
Scimago
SJR index	0.288
SJR Q rank	Q3

Pollack Periodica
Publication Model	Hybrid
Submission Fee	none
Article Processing Charge	900 EUR/article
Printed Color Illustrations	40 EUR (or 10 000 HUF) + VAT / piece
Regional discounts on country of the funding agency	World Bank Lower-middle-income economies: 50% World Bank Low-income economies: 100%
Further Discounts	Editorial Board / Advisory Board members: 50% Corresponding authors, affiliated to an EISZ member institution subscribing to the journal package of Akadémiai Kiadó: 100%
Subscription fee 2025	Online subsscription: 381 EUR / 420 USD Print + online subscription: 456 EUR / 520 USD
Subscription Information	Online subscribers are entitled access to all back issues published by Akadémiai Kiadó for each title for the duration of the subscription, as well as Online First content for the subscribed content.
Purchase per Title	Individual articles are sold on the displayed price.

Pollack Periodica
Language	English
Size	A4
Year of Foundation	2006
Volumes per Year	1
Issues per Year	3
Founder	Faculty of Engineering and Information Technology, University of Pécs
Founder's Address	H–7624 Pécs, Hungary, Boszorkány utca 2.
Publisher	Akadémiai Kiadó
Publisher's Address	H-1117 Budapest, Hungary 1516 Budapest, PO Box 245.
Responsible Publisher	Chief Executive Officer, Akadémiai Kiadó
ISSN	1788-1994 (Print)
ISSN	1788-3911 (Online)