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Application of Fiber-reinforced Concrete in Tram Track Foundation
Available online at www.sciencedirect.com
ScienceDirect Procedia Engineering 189 (2017) 836 – 840
Transportation Geotechnics and Geoecology, TGG 2017, 17-19 May 2017, Saint Petersburg, Russia
Application of fiber-reinforced concrete in tram track foundation V.V. Garbaruka, E.P. Dudkina*, V.A. Ivlieva a
Emperor Alexander I State Transport University, Moscow avenue 9, Saint Petersburg, 190031, Russia
Abstract The use of polymer fiber-reinforced concrete is one of the most promising trends in tram track development. It was first successfully used as tram track foundation in 2010-2011. The analysis of such structures has shown a number of their advantages: reduced construction time, economic benefits in terms of reducing cost and labour, and construction technology simplification. Mathematical modelling of structure strength characteristics and field testing specifying the model parameters are required for the subsequent use of fiber-reinforced concrete as tram track foundation. © 2017 The Authors. Published by Elsevier Ltd. © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and (http://creativecommons.org/licenses/by-nc-nd/4.0/). Geoecology. Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and Geoecology Keywords: fiber-reinforced concrete; tram track design; strength calculation;
Introduction Application of polymer fiber-reinforced concrete is one of the promising trends in improvement of tram track structure. Crack initiation and distribution in reinforced concrete plates is controlled by longitudinal bars, however, generated micro cracks may still promote corrosion and material spalling. Application of macro synthetic fibers instead of reinforcement steel offers many advantages: fiber-reinforced concrete has the same monolithic structure as non-reinforced concrete; concrete plates are reinforced throughout their volume, while steel bars cross only a part of the internal space; effective prevention of crack growth; easier rail fastening; simplified crack inducer installation; lower current leakage between alternating and direct current systems; better structure resistance to
* Corresponding author. Tel.: Tel.: +7-812-457-8695; fax: +7-812-457-8832. E-mail address: [email protected]
1877-7058 © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and Geoecology
doi:10.1016/j.proeng.2017.05.131
V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
effects inducing settlement shifts and bending tensions; resistance to electrocorrosion initiated by ground current effects [1, 2]. 1. Application experience In 2010, in Berlin company Rail.One together with Rosenberg Engineering Company developed special fiber-reinforced concrete meeting compliant with European and German standards and requirements to RHEDA CITY rail track system. In October 2010, this structure was first applied on a bridge in the Berliner Verkehrsbetriebe (BVG, Berlin Transport Company) tram network. [3]. The test area was divided in 2 tracks, one with traditional concrete foundation and another using the new synthetic fiber. The second track was laid using elastic base pads that separated the track from the bridge base. This increased the vertical deflection of the tram track foundation. After several weeks of operation detailed inspection of the section was carried out and cracks on the section with traditional concrete foundation were identified. No cracking was found in fiber concrete. [4]. Even after more than two years of operation in extreme weather conditions (as low as -20°C during a long period) no visible cracks were found in fibro concrete [3]. Also, a similar system was used by Verkehrsbetriebe Karlsruhe (VBK, Karlsruhe Transport Company) when reconstructing old and building new tram lines. The use of fiber-reinforced concrete structure showed a number of advantages compared with the traditional structure. For example, earlier 16.5 tons of steel bars were used for construction of one kilometer of Rheda City structure. When using fiber-reinforced concrete 2.8 tons of synthetic fibers are needed. And since fiber is added to the mixture already at the concrete factory, there are no logistical and spatial requirements at the construction site. Also, due to reduction of the amount of heavy steel components the cost of transportation of the whole structure is significantly lower. In addition, the lack of need for laying reinforcing grids reduces time and labor required for construction. Also, there is no need to insulate longitudinal reinforcement from the components of alarm systems which further reduces construction costs [5]. In Blackpool (England), in the course of modernization of a tram line with the use of signaling systems that provided to trams priority over automobile transport, the structure with reinforcing frame was replaced by the structure with steel fiber due to the need to drill additional holes for installation of the new track [6, 7]. In 2010 and 2011, in the course of expansion and reconstruction of A and C sections of tram line Nr. I. in Szeged and construction of tram line Nr. II at all sections fiber-reinforced concrete was applied with Barchip 48 fiber made in Japan. The project was a great success. A similar structure using 48 Barchip fiber was used in Tallinn (Estonia), St. Petersburg (Russia) and Budapest (Hungary) [8]. 2. Research findings In research conducted by KTH Royal Institute of Technology 3 models of no-ballast foundations were compared: model 1 - concrete slab with classic reinforcement; model 2 - concrete slab reinforced with steel fiber; and model 3 – combination of reinforcement frames and steel fiber. [9]. These studies showed that models 2 and 3 are much better than model 1 in terms of construction time, mass and cost, but are inferior in the strength characteristics. It is noted that account should be taken of "the human factor", because in the process of laying reinforcing grids there is a lot of manual work. In the process of armature binding the bodies of workers are in awkward position. In particular, during the foundation arrangement on a level with the road it is impossible to avoid uncomfortable body position. This results in fatigue and damage to the body (shoulders, spine, back, etc.). All these negative factors are excluded in case of monolithic fiber-concrete application. To determine the efficiency of fiber concrete in rail base structures the traverse shear stability was tested. Using the test installation (Fig. 1) the horizontal force through the rails was delivered to the concrete foundation, forcing it to resist the applied loads. Gradual step-by-step increase of pressure was accompanied by cracking. Each crack was registered and its width was measured.
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Figure 1 Horizontal test equipment. Testing was conducted on concrete samples with thickness of 60 and 100 mm. As a result, a graph reflecting dependence of deformation on the applied load was plotted (Fig. 2). The test showed that concrete reinforced with micro synthetic fibers can withstand a load of 8.8 and 10.2 tons respectively, depending on the thickness of the element. Both samples showed significant residual performance after appearance of the first cracks which proves that introduction of reinforcing Barchip fibers significantly improves the concrete resistance to horizontal loads.
Figure 2. Dependence of deformation on the load. A number of studies showed that replacement of steel reinforcement with polymer fiber helps reduce total carbon emissions by 50-70% [10]. PGUPS conducted dynamic testing of the performance of fiber-concrete foundation under cyclic loads. The physical tram track model shown in Figure 3 was tested. The model was loaded with a vertical dynamic force of 5
V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
Hz frequency. The maximum force was the load of a tram wheel on the rail equal to 42.5 kN, the minimum force was 5 kN. The number of exposure cycles was determined by calculation in accordance with the data of the State Unitary Enterprise "Gorelectrotrans" and corresponds to the period of tram track operation – not less than 25 years (5 Mio. cycles). The conducted dynamic testing fully confirmed the structure operability. No visual destruction in fiber-concrete base and asphalt coating was recorded. The stress in fiber concrete was significantly lower than permissible stress which proves the applicability of this structure with service life of 25 years [11.12].
Figure 3. Physical model of tram track. In order to determine the strength of fiber concrete tram track foundation first of all it is necessary to identify strength properties of fiber reinforced concrete. The properties of fiber reinforced concrete as composite material depend on the properties of its components. Main factors include the type of concrete, fiber material, and length and diameter of fiber reinforced polymer bars. Theoretical and experimental studies of fiber reinforced concrete stressstrain properties and their application experience were used to find out the effective range of structures as well as facilities and products made of them. However, fiber reinforced concrete application as tram track foundation requires further laboratory and field tests, detailed concrete and fiber material requirements, and building of a strength model for fiber-reinforced concrete tram track foundation taking into account basic material parameters and structure behavior under rolling stock conditions and other specific factors [13, 14]. 3. Calculation methods Strength calculation can be made for the tram track bearing plate using one of three methods: x As a rigid road mat x As a foundation plate x As a tram track bridge structure Strength calculation of the tram track foundation plate as a rigid road mat structure requires an analytical model adopted with regard for fiber concrete reinforcement. Then design flow is determined with the design service life of 50 years. Next, track covering design strength and reliability are calculated. It should be noted that stresses are determined in this calculation with account for reinforcing bar locations, but fiber reinforced concrete features disperse reinforcement and this should be also considered in calculation. Additionally, the contact area is identified by rail bending calculation and comparison with concrete bending followed by determination of maximum stresses that will occur in the concrete base in case of minimum rail/concrete contact area. The advantage of this method is the fact that the calculation accounts for capping layer stiffness and cyclic nature of load application. However it also has some limitations since it ignores reinforcement parameters and only concentrated load is calculated.
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Strength calculation of the tram track base plate as a bridge structure involves a bending moment in the bearing reinforced concrete base is well over the allowable one. Therefore, it is necessary to consider base behavior that must be proportional to the load applied vertically in order to ensure realistic conditions of structural behavior. Moreover, it should be borne in mind that the considered wheel pair effect will also involve bending forces and stresses occurred in the plain orthogonal to the longitudinal track axis. For this factor to be considered it is necessary to determine the width of the element to be affected by the forces from one wheel in each pair. The quality of performed calculations can be improved by calculating the tram track base plate strength under the tram load taking into account elastic behavior of the base with the modulus of subgrade reaction or deformation determined. This method has such advantages as indicated distribution of potential stresses determined by finite-element analysis. However, base behavior is ignored when calculated as a beam and it comes down to the foundation plate calculation when calculated as a plate. Strength calculation of the tram track base plate as a foundation plate requires base parameters and tram-to-plate load components to be determined. The designed structure is laid on a prepared base consisting of concrete, crushed stone and sand. The thickness of these structural layers may vary depending on specific conditions that lead to strength changes in the base on which the tram track plate is laid. Then the values of subgrade reaction moduli are calculated. After that it is necessary to define the tram plate geometry and consider the worst case of load positions. The limitation of this method is that it ignores the cyclic nature of load application. The advantages include the considered uniform elasticity of bases and indicated distribution of cross-sectional stresses in the plate. Strength calculation of the tram base plate as a foundation plate provides the most consistent results since the difference between the theoretical and experimental data is 16%. This method determines forces occurred in each finite element which makes it possible to analyze the overall stress state of the plate. This method is therefore recommended for strength calculation of the tram base plate. There is a linear dependence of the bending stresses occurred on the subplate base strength and axial load in the considered ranges of axial tram loads and subgrade reaction modulus values. This makes it possible to develop the unified summary tables of values for the forces occurred in the tram base plate as a function of subgrade reaction modulus and axial tram load for the given base plate geometry and thus simplify the process of plate strength calculation [15]. 4. Conclusion Therefore, further wide application of fiber reinforced concrete as a tram track base requires mathematic modeling of structure strength properties and field studies to specify the model parameters. The data obtained will make it possible to develop relevant regulatory documents. References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
Dudkin E.P., Paraskevopulo Yu.G., Sultanov N.N. Fiber reinforced concrete application in tramline construction // Russian Federation Transport (science, economy and practice journal). – 2012. – No. 3-4 (40-41). – P. 77-79. Dudkin E.P., Chernyaeva V.A. Areas of effective application of the urban rail transport and the possibility of their expansion // Russian Federation Transport (science, economy and practice journal). – 2015. – No. 9. – P. 48-51. http://www.railone.com/products-solutions/urban-transit/ballastless-track-systems/trams-and-commuter-railway-systems/rheda-city/ High-fibre diet for tram tracks. The Rail Engineer, October 2011, p.32-33. Clever Karlsruhe – tram tracks using synthetic fibre concrete. The Rail Engineer, December 2011, p.12-13. http://www.rail-news.com/2010/08/31/blackpool-rocks-tram-tastic-regeneration-programme/ http://gbr.sika.com/en/solutions_products/sika-markets/concrete-admixtures/sika-concrete-case-studies/fibred-concrete-case-studies.html The Beginning: The Tramway in Szeged. Innoteka, September 2014, p.18-19. Vranjkovina Alija, Zioris Stavros. Evaluation of a Tramway’s Track Slab in Conventionally Reinforced Concrete or Steel Fiber Concrete. Degree project in concrete structures, second level Stockholm, Sweden 2015. Slab track goes synthetic. International Railway Journal, September 2011, p.51-54. Dudkin E. P., Paraskevopulo Yu. G., Sultanov N. N., Paraskevopulo G. Yu. Urban rail transport: innovative designs for tram tracks on separated roadbed // Russian Federation Transport (science, economy and practice journal). – 2012. – No. 3-4 (40-41). – P. 77-79 Dudkin E.P., Benin A.V., Paraskevopulo Yu.G. Experimental Rescarch of New Tram Track Construction Operating Fatique Capacity // Advanced Materials Research Vols.- 2014. - № 1025-1026. - p. 849 – 853 Benin A.V., Dudkin E.P., Paraskevopulo u. G., Sultanov N. N. Laboratory testing of tram track design for cyclic stress // Russian Federation Transport (science, economy and practice journal). – 2014. – No. 4 (53). – P. 28-30 Dudkin E.P., Levadnaya N.V., Chernyaeva V.A. Complex approach for selection and substantiation of municipal transport type. Scientific research bulletin No.3 (8) / 2013. p. 4-13. Sultanov N.N., 2015 Feasibility study of advanced tramway structures. PhD thesis, St. Petersburg State Transport University, Russia.
ScienceDirect Procedia Engineering 189 (2017) 836 – 840
Transportation Geotechnics and Geoecology, TGG 2017, 17-19 May 2017, Saint Petersburg, Russia
Application of fiber-reinforced concrete in tram track foundation V.V. Garbaruka, E.P. Dudkina*, V.A. Ivlieva a
Emperor Alexander I State Transport University, Moscow avenue 9, Saint Petersburg, 190031, Russia
Abstract The use of polymer fiber-reinforced concrete is one of the most promising trends in tram track development. It was first successfully used as tram track foundation in 2010-2011. The analysis of such structures has shown a number of their advantages: reduced construction time, economic benefits in terms of reducing cost and labour, and construction technology simplification. Mathematical modelling of structure strength characteristics and field testing specifying the model parameters are required for the subsequent use of fiber-reinforced concrete as tram track foundation. © 2017 The Authors. Published by Elsevier Ltd. © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and (http://creativecommons.org/licenses/by-nc-nd/4.0/). Geoecology. Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and Geoecology Keywords: fiber-reinforced concrete; tram track design; strength calculation;
Introduction Application of polymer fiber-reinforced concrete is one of the promising trends in improvement of tram track structure. Crack initiation and distribution in reinforced concrete plates is controlled by longitudinal bars, however, generated micro cracks may still promote corrosion and material spalling. Application of macro synthetic fibers instead of reinforcement steel offers many advantages: fiber-reinforced concrete has the same monolithic structure as non-reinforced concrete; concrete plates are reinforced throughout their volume, while steel bars cross only a part of the internal space; effective prevention of crack growth; easier rail fastening; simplified crack inducer installation; lower current leakage between alternating and direct current systems; better structure resistance to
* Corresponding author. Tel.: Tel.: +7-812-457-8695; fax: +7-812-457-8832. E-mail address: [email protected]
1877-7058 © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
(http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the International conference on Transportation Geotechnics and Geoecology
doi:10.1016/j.proeng.2017.05.131
V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
effects inducing settlement shifts and bending tensions; resistance to electrocorrosion initiated by ground current effects [1, 2]. 1. Application experience In 2010, in Berlin company Rail.One together with Rosenberg Engineering Company developed special fiber-reinforced concrete meeting compliant with European and German standards and requirements to RHEDA CITY rail track system. In October 2010, this structure was first applied on a bridge in the Berliner Verkehrsbetriebe (BVG, Berlin Transport Company) tram network. [3]. The test area was divided in 2 tracks, one with traditional concrete foundation and another using the new synthetic fiber. The second track was laid using elastic base pads that separated the track from the bridge base. This increased the vertical deflection of the tram track foundation. After several weeks of operation detailed inspection of the section was carried out and cracks on the section with traditional concrete foundation were identified. No cracking was found in fiber concrete. [4]. Even after more than two years of operation in extreme weather conditions (as low as -20°C during a long period) no visible cracks were found in fibro concrete [3]. Also, a similar system was used by Verkehrsbetriebe Karlsruhe (VBK, Karlsruhe Transport Company) when reconstructing old and building new tram lines. The use of fiber-reinforced concrete structure showed a number of advantages compared with the traditional structure. For example, earlier 16.5 tons of steel bars were used for construction of one kilometer of Rheda City structure. When using fiber-reinforced concrete 2.8 tons of synthetic fibers are needed. And since fiber is added to the mixture already at the concrete factory, there are no logistical and spatial requirements at the construction site. Also, due to reduction of the amount of heavy steel components the cost of transportation of the whole structure is significantly lower. In addition, the lack of need for laying reinforcing grids reduces time and labor required for construction. Also, there is no need to insulate longitudinal reinforcement from the components of alarm systems which further reduces construction costs [5]. In Blackpool (England), in the course of modernization of a tram line with the use of signaling systems that provided to trams priority over automobile transport, the structure with reinforcing frame was replaced by the structure with steel fiber due to the need to drill additional holes for installation of the new track [6, 7]. In 2010 and 2011, in the course of expansion and reconstruction of A and C sections of tram line Nr. I. in Szeged and construction of tram line Nr. II at all sections fiber-reinforced concrete was applied with Barchip 48 fiber made in Japan. The project was a great success. A similar structure using 48 Barchip fiber was used in Tallinn (Estonia), St. Petersburg (Russia) and Budapest (Hungary) [8]. 2. Research findings In research conducted by KTH Royal Institute of Technology 3 models of no-ballast foundations were compared: model 1 - concrete slab with classic reinforcement; model 2 - concrete slab reinforced with steel fiber; and model 3 – combination of reinforcement frames and steel fiber. [9]. These studies showed that models 2 and 3 are much better than model 1 in terms of construction time, mass and cost, but are inferior in the strength characteristics. It is noted that account should be taken of "the human factor", because in the process of laying reinforcing grids there is a lot of manual work. In the process of armature binding the bodies of workers are in awkward position. In particular, during the foundation arrangement on a level with the road it is impossible to avoid uncomfortable body position. This results in fatigue and damage to the body (shoulders, spine, back, etc.). All these negative factors are excluded in case of monolithic fiber-concrete application. To determine the efficiency of fiber concrete in rail base structures the traverse shear stability was tested. Using the test installation (Fig. 1) the horizontal force through the rails was delivered to the concrete foundation, forcing it to resist the applied loads. Gradual step-by-step increase of pressure was accompanied by cracking. Each crack was registered and its width was measured.
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V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
Figure 1 Horizontal test equipment. Testing was conducted on concrete samples with thickness of 60 and 100 mm. As a result, a graph reflecting dependence of deformation on the applied load was plotted (Fig. 2). The test showed that concrete reinforced with micro synthetic fibers can withstand a load of 8.8 and 10.2 tons respectively, depending on the thickness of the element. Both samples showed significant residual performance after appearance of the first cracks which proves that introduction of reinforcing Barchip fibers significantly improves the concrete resistance to horizontal loads.
Figure 2. Dependence of deformation on the load. A number of studies showed that replacement of steel reinforcement with polymer fiber helps reduce total carbon emissions by 50-70% [10]. PGUPS conducted dynamic testing of the performance of fiber-concrete foundation under cyclic loads. The physical tram track model shown in Figure 3 was tested. The model was loaded with a vertical dynamic force of 5
V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
Hz frequency. The maximum force was the load of a tram wheel on the rail equal to 42.5 kN, the minimum force was 5 kN. The number of exposure cycles was determined by calculation in accordance with the data of the State Unitary Enterprise "Gorelectrotrans" and corresponds to the period of tram track operation – not less than 25 years (5 Mio. cycles). The conducted dynamic testing fully confirmed the structure operability. No visual destruction in fiber-concrete base and asphalt coating was recorded. The stress in fiber concrete was significantly lower than permissible stress which proves the applicability of this structure with service life of 25 years [11.12].
Figure 3. Physical model of tram track. In order to determine the strength of fiber concrete tram track foundation first of all it is necessary to identify strength properties of fiber reinforced concrete. The properties of fiber reinforced concrete as composite material depend on the properties of its components. Main factors include the type of concrete, fiber material, and length and diameter of fiber reinforced polymer bars. Theoretical and experimental studies of fiber reinforced concrete stressstrain properties and their application experience were used to find out the effective range of structures as well as facilities and products made of them. However, fiber reinforced concrete application as tram track foundation requires further laboratory and field tests, detailed concrete and fiber material requirements, and building of a strength model for fiber-reinforced concrete tram track foundation taking into account basic material parameters and structure behavior under rolling stock conditions and other specific factors [13, 14]. 3. Calculation methods Strength calculation can be made for the tram track bearing plate using one of three methods: x As a rigid road mat x As a foundation plate x As a tram track bridge structure Strength calculation of the tram track foundation plate as a rigid road mat structure requires an analytical model adopted with regard for fiber concrete reinforcement. Then design flow is determined with the design service life of 50 years. Next, track covering design strength and reliability are calculated. It should be noted that stresses are determined in this calculation with account for reinforcing bar locations, but fiber reinforced concrete features disperse reinforcement and this should be also considered in calculation. Additionally, the contact area is identified by rail bending calculation and comparison with concrete bending followed by determination of maximum stresses that will occur in the concrete base in case of minimum rail/concrete contact area. The advantage of this method is the fact that the calculation accounts for capping layer stiffness and cyclic nature of load application. However it also has some limitations since it ignores reinforcement parameters and only concentrated load is calculated.
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V.V. Garbaruk et al. / Procedia Engineering 189 (2017) 836 – 840
Strength calculation of the tram track base plate as a bridge structure involves a bending moment in the bearing reinforced concrete base is well over the allowable one. Therefore, it is necessary to consider base behavior that must be proportional to the load applied vertically in order to ensure realistic conditions of structural behavior. Moreover, it should be borne in mind that the considered wheel pair effect will also involve bending forces and stresses occurred in the plain orthogonal to the longitudinal track axis. For this factor to be considered it is necessary to determine the width of the element to be affected by the forces from one wheel in each pair. The quality of performed calculations can be improved by calculating the tram track base plate strength under the tram load taking into account elastic behavior of the base with the modulus of subgrade reaction or deformation determined. This method has such advantages as indicated distribution of potential stresses determined by finite-element analysis. However, base behavior is ignored when calculated as a beam and it comes down to the foundation plate calculation when calculated as a plate. Strength calculation of the tram track base plate as a foundation plate requires base parameters and tram-to-plate load components to be determined. The designed structure is laid on a prepared base consisting of concrete, crushed stone and sand. The thickness of these structural layers may vary depending on specific conditions that lead to strength changes in the base on which the tram track plate is laid. Then the values of subgrade reaction moduli are calculated. After that it is necessary to define the tram plate geometry and consider the worst case of load positions. The limitation of this method is that it ignores the cyclic nature of load application. The advantages include the considered uniform elasticity of bases and indicated distribution of cross-sectional stresses in the plate. Strength calculation of the tram base plate as a foundation plate provides the most consistent results since the difference between the theoretical and experimental data is 16%. This method determines forces occurred in each finite element which makes it possible to analyze the overall stress state of the plate. This method is therefore recommended for strength calculation of the tram base plate. There is a linear dependence of the bending stresses occurred on the subplate base strength and axial load in the considered ranges of axial tram loads and subgrade reaction modulus values. This makes it possible to develop the unified summary tables of values for the forces occurred in the tram base plate as a function of subgrade reaction modulus and axial tram load for the given base plate geometry and thus simplify the process of plate strength calculation [15]. 4. Conclusion Therefore, further wide application of fiber reinforced concrete as a tram track base requires mathematic modeling of structure strength properties and field studies to specify the model parameters. The data obtained will make it possible to develop relevant regulatory documents. References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
Dudkin E.P., Paraskevopulo Yu.G., Sultanov N.N. Fiber reinforced concrete application in tramline construction // Russian Federation Transport (science, economy and practice journal). – 2012. – No. 3-4 (40-41). – P. 77-79. Dudkin E.P., Chernyaeva V.A. Areas of effective application of the urban rail transport and the possibility of their expansion // Russian Federation Transport (science, economy and practice journal). – 2015. – No. 9. – P. 48-51. http://www.railone.com/products-solutions/urban-transit/ballastless-track-systems/trams-and-commuter-railway-systems/rheda-city/ High-fibre diet for tram tracks. The Rail Engineer, October 2011, p.32-33. Clever Karlsruhe – tram tracks using synthetic fibre concrete. The Rail Engineer, December 2011, p.12-13. http://www.rail-news.com/2010/08/31/blackpool-rocks-tram-tastic-regeneration-programme/ http://gbr.sika.com/en/solutions_products/sika-markets/concrete-admixtures/sika-concrete-case-studies/fibred-concrete-case-studies.html The Beginning: The Tramway in Szeged. Innoteka, September 2014, p.18-19. Vranjkovina Alija, Zioris Stavros. Evaluation of a Tramway’s Track Slab in Conventionally Reinforced Concrete or Steel Fiber Concrete. Degree project in concrete structures, second level Stockholm, Sweden 2015. Slab track goes synthetic. International Railway Journal, September 2011, p.51-54. Dudkin E. P., Paraskevopulo Yu. G., Sultanov N. N., Paraskevopulo G. Yu. Urban rail transport: innovative designs for tram tracks on separated roadbed // Russian Federation Transport (science, economy and practice journal). – 2012. – No. 3-4 (40-41). – P. 77-79 Dudkin E.P., Benin A.V., Paraskevopulo Yu.G. Experimental Rescarch of New Tram Track Construction Operating Fatique Capacity // Advanced Materials Research Vols.- 2014. - № 1025-1026. - p. 849 – 853 Benin A.V., Dudkin E.P., Paraskevopulo u. G., Sultanov N. N. Laboratory testing of tram track design for cyclic stress // Russian Federation Transport (science, economy and practice journal). – 2014. – No. 4 (53). – P. 28-30 Dudkin E.P., Levadnaya N.V., Chernyaeva V.A. Complex approach for selection and substantiation of municipal transport type. Scientific research bulletin No.3 (8) / 2013. p. 4-13. Sultanov N.N., 2015 Feasibility study of advanced tramway structures. PhD thesis, St. Petersburg State Transport University, Russia.