Investigation of the effectiveness of strengthening with FRP applied in metal elements of suspension roof: an analytical approach




methods of strengthening, FRP material, metal structures, suspended rigid threads, stress-strain state, computational methods, composite materials, reinforcement, defects, damage, reconstruction, bearing capacity


The building patrimony of Ukraine includes various examples of metallic structures, especially applied for industrial purposes and in large-span structures. The use of metal structures in construction is due primarily to their mechanical properties. They are frost-resistant and able to withstand temperatures down to -65 degrees as well as they are hard, durable, strong and reliable. They can also be used in areas with high seismic activity. However, as in the case of other types of structures, there is a need to restore or strengthen metal structures due to structural defects, wear of load-bearing elements, as well as to increase the load-bearing capacity. In several situations, strengthening with Fiber Reinforced Polymer composites (FRP) gives better results. The current article deals specifically with this strengthening technique. The main cultural reason to restore the old metallic structures and provide a structural functionality, is based on the need to preserve not only their historical origins but also the scenery value of the places in which they are located. That is why the strengthening should be carried out with the aim of maintaining the original design idea.

Due to the long-term operation without timely maintenance and major repair, unique and metal large-span structures require strengthening of the load-bearing structures. It is especially important to choose the most efficient method, both in terms of reliability and cost effectiveness. This can lead to the long term interruption of the structure operation and production process, or the inability to use the adjacent territory due to the reconstruction work. At the same time, it is necessary to preserve not only the structure as a whole, but also the external architectural appearance.

Traditional methods of strengthening are effective, but in some cases not effective or not applicable for use. An example is the increase of the load-bearing structures of the buildings, preserving the external appearance of which is the determining factor. In this case, the use of the discussed methods can be justified alternative. Disadvantages of steel panels and rods for strengthening are possible corrosion, considerable weight, need for high labor content of the work, and consequently the high cost of labor required to perform the work that need large area.

Nowadays, one of the most dynamic types of large-span structures in architectural and structural view are suspension roofs. The aim of the research is the evaluation of the bearing capacity of the suspended rigid threads strengthened with CFRP (carbon fiber reinforced polymer) laminates and provision the general recommendations to implement reconstruction and strengthening with this type of material. Therefore it was considered variant of strengthening suspended bending-rigid fibers by composite materials. Computations are performed in software ABAQUS, as a result of which the percentage reduction in vertical deformation was 26.6% for bending-rigid fibers strengthened with CFRP laminates. The value of tensile stresses reduced by about 14 %.

The obtained results of the study confirm the need for further studies and research.

Author Biographies

Iryna Rudnieva, Kyiv National University of Construction and Architecture

Candidate of Technical Science, Associate Professor of the Department of Strength of Materials

Yurii Priadko, Beijing International Education Institute

Candidate of Technical Science, Researcher, Associate Professor

Hennadii Tonkacheiev, Kyiv National University of Construction and Architecture

Doctor of Technical Sciences, Professor of the Department of Construction Technologies, Vice-Rector for Educational and Methodological Work

Mykola Priadko, 'SVK' LLC

Candidate of Technical Science, Associate Professor, Director


Luke, S. & Mouchel Consulting. The Use of Carbon Fibre Plates for the Strengthening of Two Metallic Bridges of a Historie Nature in the UK. In lG. Teng (ed.), FRP Composites in Civil Engineering, Vol. II.

Ceriolo, L. & Di Tommaso, A. 2001. Cast Iron Bridge Failure Due to Impact: reduced Vulnerability thcough FRP Composite MateriaIs Strengthening. In National Con! on Structure failures and reliability of civil constructions; Proc. symp., Istituto Universitario di Architettura di Venezia, 6-7 December 2001.

Miller, T.e., Chajes, M.J" Mertz, D.R. & Hastyings, J. 2001. Strengthening of a Steel Bridge Girder Using CFRP Plates, Journal of bridge engineering, ASCE, 6(6): from 514-522,

Giosuè Boscato. Numerical analysis and experimental tests on dynamic behaviour of GFRP pultruded elements for conservation of the architectural and environmental heritage. PhD. Dissertation. University Iuav of Venice, Venice, Italy, 2009. P 215.

CNR-DT 202/2005 «Guidelines for the Design and Construction of Externally Bonded FRP Systems for Strengthening Existing Structures. Metallic structures. Preliminary study». ROME – CNR, 2007. 57 p.

ACI Committee 440 (2002) Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures (ACI 440.2R-02). American Concrete Institute, Farmington Hills, MI, USA.

FIB bulletin 14. Externally bonded FRP reinforcement for RC structures. July 2001

EN1990 Eurocode 0: Basis of structural design: EN 1990:2002+A1. [European Standard]. Brussels: Management Centre, 2002. 116 p.

EN1991 Eurocode 1: Actions on structures.

EN 1993 Eurocode 3: Design of steel structures.

Eurocode 8 - Design of structures for earthquake resistance Part 3: Assessment and retrofitting of buildings. EN 1998-3:2004. European Committee for Standardisation (November 2004)

DBN V.1.2-14:2018. Zahalni pryntsypy zabespechennia nadiinosti ta konstruktyv-noi bezpeky budivel, sporud, budivelnykh konstruktsii ta osnov. (General principles of ensuring the reliability and structural safety of buildings, structures, building structures and foundations) / Minrehionbud Ukrainy. – K.: DP «Ukrarkhbudinform», 2018. [in Ukrainian].

DBN V.1.2-2:2006. Navantazhennia i vplyvy. Normy proektuvannia. (Loads and influences. Design standards) / Minbudarkhitektury Ukrainy. – K.: Stal, 2006. [in Ukrainian].

DBN V.2.6-198:2014. Stalevi konstruktsii. Normy proektuvannia. (Steel structures. Design standards.) / Minrehion Ukrainy. – K.: DP «Ukrarkhbudinform», 2014. [in Ukrainian].

DBN A.1.1-94:2010. Proektuvannia budivelnykh konstruktsii za Yevrokodamy. Osnovni polozhennia. (Design of building structures according to Eurocode. Basic Provisions.) / Minrehionbud Ukrainy. – K.: DP «Ukrarkhbudinform», 2012. [in Ukrainian].

DSTU B V.1.2.-3:2006. Prohyny i peremishchennia. Vymohy proektuvannia. (Deflections and displacements. Design requirements.) /Minbud Ukrainy. – K.: Stal, 2006. [in Ukrainian].

V. Zerbo, A. Di Tommaso & L. Ceriolo. FRP strengthening systems for metallic structures: a state ofthe art. Structural Analysis of Historical Constructions - Modena, Lourenço & Roca (eds), 2005. Taylor & Francis Group, London, ISBN 04 15363799.

I. Rudnieva, Yu. Priadko, M. Priadko, H. Tonkacheiev. Osoblyvosti ta perspektyvy vykorystannia tekhnolohii pidsylennia budivelnykh konstruktsii kompozytsiinymy materialamy pry rekonstruktsii sporud (Features and prospects for the use of technologies for strengthening building structures with composite FRP-materials during reconstruction of buildings) / Zbirnyk naukovykh prats "BUDIVELNI KONSTRUKTsII. TEORIIA I PRAKTYKA". № 7 (2020), c.12-22. DOI: 10.32347/2522-4182.7.2020.12-22 [in Ukrainian].

B. Täljsten, FRP strengthening of existing concrete structures – design guidelines (fourth edition), Luleå, Sweden: Luleå University of Technology; ISBN 91-89580-03-6, (2006)

Rudneva Y.N., Priadko Yu.N. Sravnytelnыi analyz Evrokodov y natsyonalnыkh standartov Ukraynы, v tom chysle chastnыkh koэffytsyentov nadezhnosty y ucheta faktora vremeny, pry proektyrovanyy konstruktsyi (Comparative analysis of Eurocodes and national standards of Ukraine, including partial reliability factors and taking into account the time factor in the design of structures) / Naukovo-vyrobnychyi zhurnal «Promyslove budivnytstvo ta inzhenerni sporudy», №1, 2020, str.39-45. [in Rusian].

M.V. Priadko, I.M. Rudnieva, Yu.M. Priadko. Obstezhennia ta pidsylennia budivelnykh konstruktsii promyslovykh budivel (Inspection and strengthening of building structures of industrial buildings) / Navchalnyi posibnyk. – Kyiv: KNUBA, 2018. – 332 s. [in Ukrainian].

I. Rudnieva, Yu. Priadko, M. Priadko. Analiz prychyn obvalennia pokrivel vyrobnychykh budivel. (Investigation of the roof collapse causes of industrial buildings.) / Zbirnyk naukovykh prats "Budivelni konstruktsii. Teoriia i praktyka". № 6 (2020), c.85-93. [in Ukrainian].

Lanier, B.K. Study in the Improvement in Strength and Stiffness Capacity of Steel Multi- sided Monopole Towers Utilizing Carbon Fiber Reinforced Polymers as a Retrofitting Mechanism. M.S. Thesis, North Carolina State University, Raleigh, NC, 2005.

Cadei, J.M.C., Stratford T.J., Hollaway L.C., Duckett W.G. Strengthening metallic structures using externally bonded fibre-reinforced polymers, Report CIRIA C595. London: CIRIA. 2004.

Miller, T.C., Chajes, M.J., Mertz, D.R. and Hastyings, J. Strengthening of a Steel Bridge Girder Using CFRP Plates, Journal of bridge engineering, ASCE, 2001. 6(6): p. 514-522.

DSTU B V.3.1-2:2016. Remont i pidsylennia nesuchykh i ohorodzhuvalnykh budivelnykh konstruktsii ta osnov budivel i sporud (Repair and strengthening of load-bearing and enclosing building structures and foundations of buildings and structures). – Kyiv, 2017. – 68s. [in Ukrainian].

Posobye po obsledovanyiu stroytelnыkh konstruktsyi zdanyi (Manual for the survey of building structures of buildings). AO TsNYYPromzdanyi. – M.: 1997.- 141s. [in Rusian].

DSTU-N B V.1.2-18:2016 Nastanova shchodo obstezhennia budivel i sporud dlia vyznachennia ta otsinky yikh tekhnichnoho stanu. (Guidelines for the survey of buildings and structures for the determination and assessment of their technical condition.) – Kyiv: DP «UkrNDNTs», 2017. – 44 s. [in Ukrainian].

UNI EN 473:2008-11. Non-destructive testing - Qualification and certification of NDT personnel - General principles.

UNI CEI EN 45013:1990. General criteria for certification bodies operating certification of personnel.

Rudneva Y.N. 2006. Osobennosty prostranstvennoi rabotы vysiacheho pokrыtyia, obrazovannoho systemoi zhestkykh nytei (Behavior features of spatial work of suspended rod shell by system of bending-rigid fibers). Dys. kand. tekhn. nauk: 05.23.01 / Donbacskaia natsyonalnaia akademyia stroytelstva y arkhytekturы. Makeevka, 263 s. [in Rusian].

Orzhekhovskiy A., Priadko I., Tanasoglo A, Fomenko S. Design of stadium roofs with a given level of reliability. Engineering Structures. 2020. No. 209.

I.N. Priadko, I.N. Rudnieva,Y. Ribakov, H. Bartolo. A new approach to the design of suspension roof systems. «Strength of Materials and Theory of Structures». «Strength of Materials and Theory of Structures», 2020. № 104 – р.191-220. DOI:

Amr Shaat, David Schnerch, Amir Fam, And Sami Rizkalla. Retrofit of steel structures using fiber reinforced polymers (frp). State-of-the-art, 2003.

A. Shaat And A. Fam. Control of overall buckling of hss slender steel columns using CFRP plates. Asia-pacific Conference on FRP in Structures (APFIS 2007). International Institute for FRP in Construction.

Bassetti, A., Nussbaumer, A., Hirt, M. 2000. Crack Repair and Fatigue Life Extension of Riveted Bridge Members using Composite Materials. In Proc., Bridge Engineering Conference, ESE-IABSE-FIB, 26-30 March 2000, Sharm El Sheik (Egypt).

Jones, S.C. and Civjan, S.A. (2003), “Application of Fiber Reinforced Polymer Overlays to Extend to Steel Fatigue Life,” ASCE Journal of Composites for Construction, 7, pp. 331-338.

Miller, T.C. (2000), “The Rehabilitation of Steel Bridge Girders Using Advanced Composite Materials”, M.S. Thesis, University of Delaware, Newark, DE, 58-79.

Tavakkolizadeh, M., and Saadatmanesh, H. 2003. Fatigue Strength of Steel Girders Strengthened With Carbon Fiber Reinforced Polymer Patch, Journal of Structural Engineering, ASCE, 2(129): from 186-196.

Priadko I.N., Mushchanov V.P., Bartolo E., Vatin N.I., Rudnieva I.N. Improved numerical methods in reliability analysis of suspension roof joints. Magazine of Civil Engineering. 2016. No. 5. Pp. 27–41. DOI: 10.5862/MCE.65.3.

V. P. Mushchanov, I. M. Rudnieva, Yu. M. Priadko. Napruzheno-deformovanyi stan vysiachoi systemy, utvorenoi systemoiu zghynalno-zhorstkykh nytok, z urakhuvanniam podatlyvosti opor (Intense-deformed condition of suspended system of bending-rigid fibers at the account of pliability of supports) / Zhurnal «Metallycheskye konstruktsyy». – T. 18. - № 1. Makiivka, 2012. – S. 5-16. [in Ukrainian].

Mushchanov V.P., Rudneva I.N., Priadko Yu.M. Эksperymentalnoe yssledovanye bloka vysiachykh ferm prostranstvennoi sterzhnevoi obolochky (Experimental investigation of suspension trusses block of spacial rod-shaped covering) / Sb. nauchnыkh trudov «Sovremennыe stroytelnыe konstruktsyy yz metalla y drevesynы». – chast 1. Odessa: OHASA, 2005. – S. 138-144. [in Rusian].

Pichugin S. F. Nadezhnost stalnyih konstruktsiy proizvodstvennyih zdaniy [Durability of steel structures of industrial buildings]. Poltava: ASV; 2011. [in Rusian].

I.N. Rudnieva. Сomparative analysis of strengthening of building structures (masonry, metal structures, reinforced concrete) using FRP-materials and traditional methods during reconstruction. «Strength of Materials and Theory of Structures», 2020. № 105 – р.267-291.

ISO 2394:2015. International standard. General principles on reliability for structures. ISO 2015. Pages 112.

Risk assessment in engineering. Principles, system representation and risk criteria. JCSS – Joint Committee on Structural Safety. Edited by M.H. Faber. – June 2008. Pages 35.