Research projects and networks

In Progress

Finished

Contact Form

FRPreDur - Short and long-term structural behaviour of concrete elements flexurally strengthened with prestressed CFRP laminates

2015-11-02

The main objective of the present research project was to contribute to the knowledge on short and long-term structural behaviour of RC elements strengthened in flexural with pre-stressed CFRP laminates under various specific application environments, load conditions and chemical degradation.

The project involved the three following components: an experimental program, numerical simulations and design recommendations. The experimental program was supported in reinforced concrete slabs strengthened in flexural with prestressed CFRP laminates. The influence of the prestressed system, prestressed level and the existing damage on the immediate and time-dependent losses under the effect of chlorides, sustained stress (creep), freeze-thaw, wet/dry and thermal cycles, were the main variables to be studied. The test results obtained from the experimental programs were used for predicting the service life behaviour of prestressed slabs, as well as the ultimate strength supported in some numerical models. These numerical models were implemented in the FEMIX program, which is a general purpose finite element software system. 2D and 3D models were used in the simulation of the structural elements. The concrete was simulated using an elasto-plastic multi-fixed smeared crack model. FRP’s was assumed as linear elastic until reach the ultimate stress. The simulation of the FRP/concrete interface was done with suitable models. The degradation effects and losses were reflected on the constitutive models of concrete, reinforcements, FRP, epoxy adhesive and, on the interface. Design recommendations were elaborated using the results obtained in the experimental programs and derived from parametric studies performed by numerical simulations. Finally, since the Principal Investigator of the present project is the secretary of the RILEM Technical Committee 234-DUC - Design procedures for the use of composites in strengthening of reinforced concrete structures, the most important conclusions were also presented to the Committee and were included in documents to be published. Additionally, the main results were also disseminated in the meetings of the COST Action TU1207 - Next Generation Design Guidelines for Composites in Construction and fib TG 5.1.

Project ID: PTDC/ECM-EST/2424/2012

Coordinator: José Manuel de Sena Cruz

Promoting Institution: University of Minho

Financing Institution: Fundação para a Ciência e a Tecnologia

Budget: €157.498,00

Start date: 01-03-2013

End date: 30-09-2015

Companies/Institution that collaborated in this project:
- S&P Clever Reinforcement Ibérica, Lda. (www.reinforcement.ch)
- Artecanter - Indústria de Transformação de Granitos, Lda. (www.artecanter.com)
- Tecnipor - Gomes & Taveira Lda. (www.tecnipor.com.pt)
- Vialam - Indústrias Metalúrgicas e Metalomecânicas, Lda.
- Hilti Portugal (www.hilti.pt)
- Novo Modelo Europa, S.A. (www.nmeuropa.pt)
- Sika Portugal - Produtos Construção e Indústria, S.A. (www.sika.pt)
- HBM FiberSensing (www.fibersensing.com)

The main objectives of the present project were:

1 - The investigation of the fundamental parameters that influence, under short and long-term actions, the performance of pre-stressed CFRP laminates in the context of flexural strengthening;

2 - Evaluate the long-term behaviour of CFRP laminate, adhesive and concrete in terms of creep, relaxation and shrinkage and identify the critical environments that accelerate their effect;

3 - The obtainment of predictions of service life due to the long-term actions;

4 - The achievement of reduction factors for the studied environments;

5 - The obtainment of stress limitation values for long-term actions;

6 - The development of numerical models to simulate the studied degradation effects in concrete elements strengthened with pre-stressed CFRP laminates.

A1 - Project's management

A2 - Long-term behaviour of CFRP laminate, adhesive and concrete

A3 - Short and long-term behaviour the RC slabs flexurally strengthened with pre-stressed CFRP laminates under sustained load

A4 - Long-term behaviour the RC slabs flexurally strengthened with pre-stressed CFRP laminates under distinct environmental actions

A5 - Numerical prediction and design recommendations of short and long-term behaviour the RC slabs flexurally strengthened with pre-stressed CFRP laminates

CBPAT2014 – 1º Congresso Brasileiro de Patologia das Construções, 21 to 23 May 2014, Foz de Iguaçu, Brazil.

CICE2014 – The 7th International Conference on FRP Composites in Civil Engineering – CICE2014, 20 to 22 August 2014, Vancouver, Canada.

5th TU1207 – 5th Meeting of COST Action TU1207, 19 to 21 May 2015, Lecce, Italy.

6th TU1207 – 6th Meeting of COST Action TU1207, 8 to 9 October, 2015, Barcelona, Spain.

SMAR2015 – Third Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures, 7 to 9 September 2015, Antalya, Turkey.

SPREB-FRP 2015 – 3º Seminário sobre o Projeto de Reforço de Estruturas de Betão com FRP’s (SPREB-FRP 2015), 18 September 2015, University of Minho, Guimarães.

Seminar

1. SPREB-FRP 2015 - 3rd Seminar on design strengthening of concrete structures with FRP materials, held at the University of Minho, Guimarães, on last 18th September, 2015. The seminar, attended by 50 participants, included the following themes: (i) the use of pre-stressed FRP in the strengthening of RC structures; (ii) flexural behaviour of RC structures strengthened with pre-stressed strips according to the NSM technique; (iii) cases of recent application of FRP in RC structures. In the afternoon, special focus was taken on the project FRPreDur.


PhD theses

2. “Short and long-term structural behaviour of concrete elements flexurally strengthened with prestressed CFRP laminates.” PhD thesis of Luís Correia, Doctoral Programme in Civil Engineering, University of Minho (Supervising Team: José Sena Cruz & Paulo França). [To be concluded 2016]

3. “Short and long-term structural behaviour of concrete elements flexurally strengthened with prestressed CFRP laminates by using the gradient method” PhD thesis of Tiago Teixeira, Doctoral Programme in Civil Engineering, University of Minho (Supervising Team: José Sena Cruz & Julien Michels). [The PhD student past away last May 2015]


MSc theses

4. “Flexural strengthening of RC slab with prestressed CFRP laminates [Reforço à flexão de lajes de betão armado com laminados de CFRP pré-esforçados]”. MSc Thesis of Ricardo Azevedo, University of Minho, approved on 30th of July 2015 (Supervising Team: José Sena Cruz). [in Portuguese]

5. “Influence of the epoxy adhesive on the performance of the concrete elements strengthened with NSM-CFRP systems”. MSc Thesis of Anja Borojevic, Università degli Studi di Padova, approved on 15th of October 2015 (Supervising Team: José Sena Cruz, Carlo Pellegrino).

6. “Reinforced concrete slabs strengthened with FRP: experimental and finite element’s behaviour”. MSc Thesis of Fabio Panella, Università degli Studi di Padova, approved on 26th of October 2015 (Supervising Team: Gian Piero Lignola, Francesca Ceroni, José Sena Cruz).


Books

7. Sena-Cruz, J.M.; Correia, L. (Editores) “3rd Seminar on design strengthening of concrete structures with FRP materials (SPREB-FRP 2015) [3º Seminário sobre o projeto de reforço de estruturas de betão com FRP’s (SPREB-FRP 2015)].” Department of Civil Engineering, School of Engineering, University of Minho, Guimarães, ISBN 978-989-8793-02-7, 36 pp., 2015.


Book chapters

8. Michels, J.; Barros, J.; Costa, I.; Sena-Cruz, J.; Czaderski, C.; Giacomin, C.; Kotynia, R.; Lees, J.; Pellegrino, C.; Zile, E. (2015) “Prestressed FRP Systems” Design Procedures for the Use of Composites in Strengthening of Reinforced Concrete, RILEM State-of-the-Art Reports 19, C. Pellegrino and J. Sena-Cruz (eds.), 263-301.


Papers in ISI international journals

9. Correia, L.; Teixeira, T.; Michels, J.; Almeida, J.; Sena-Cruz, J. (2015) “Flexural behaviour of RC slabs strengthened with prestressed CFRP strips using different anchorage systems” Composites Part B, 81: 158–170.

10. Sena-Cruz, J.; Michels, J.; Harmanci, Y.; Correia, L. (2015) “Flexural strengthening of RC slabs with prestressed CFRP strips using different anchorage systems” Polymers, 7: 2100–2188.

11. Silva, P.; Fernandes, P.; Sena-Cruz, J.; Xavier, J.; Castro, F.; Soares, D.; Carneiro, V. (2015) “Effects of different environmental conditions on the mechanical characteristics of a structural epoxy” Composites Part B. [Accepted for publication]

12. Benedetti, A.; Fernandes, P.; Granja, J.L.; Sena-Cruz, J.; Azenha, M. (2015) “Influence of temperature on the curing of an epoxy adhesive and its influence on bond behaviour of NSM-CFRP systems” Composites Part B. [Re-submitted]


Papers in national journals

13. Correia, L.; Sena-Cruz, J.; Michels, J.; França, P. (2015) “Reforço à flexão de lajes de betão armado com laminados de CFRP pré-esforçados usando distintos métodos de ancoragem” Revista de Engenharia Civil. [Submetido]


Papers in international conferences

14. Sena-Cruz, J.; Correia, L.; Teixeira, T.; Michels, J. (2014) “Flexural strengthening of RC slabs with prestressed CFRP strips: serviceability and ultimate load state behavior”, CBPAT2014 – 1º Congresso Brasileiro de Patologia das Construções, 21 to 23 May, Foz de Iguaçu, Brazil, 14 pp.

15. Correia, L.; Teixeira, T.; Sena-Cruz, J.; Michels, J. (2014) “Flexural strengthening of RC slabs with prestressed CFRP strips using different anchorage systems”, The 7th International Conference on FRP Composites in Civil Engineering – CICE2014, 20 to 22 August, Vancouver, Canada, 6 pp.

16. Fernandes, P.; Silva, P.; Correia, L.; Sena-Cruz, J. (2015) “Durability of an epoxy adhesive and a CFRP laminate under different exposure conditions”, SMAR2015 – Third Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures, 7 to 9 September, Antalya, Turkey, 8 pp.

17. Silva, P.; Sena-Cruz, J.; Azenha, M.; Escusa, G. (2015) “Experimental investigation on creep behaviour of an epoxy adhesive”, SMAR2015 – Third Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures, 7 to 9 September, Antalya, Turkey, 8 pp.

18. Benedetti, A.; Fernandes, P.; Granja, J.; Azenha, M.; Sena-Cruz, J. (2015) “Effects of curing temperature on pull-out behavior and stiffness evolution of epoxy adhesives for NSM-FRP applications”, SMAR2015 – Third Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures, 7 to 9 September, Antalya, Turkey, 8 pp.


Papers in national conferences

19. Teixeira, T.; Correia, L.; Sena-Cruz, J.; Michels, J. (2014) “Reforço à flexão de lajes de betão armado com laminados de CFRP pré-esforçados: comportamento em estado limite último e de utilização.” JPEE2014 - 5as Jornadas Portuguesas de Engenharia de Estruturas, 26 to 28 November, LNEC, Lisbon, 14 pp. [in Portuguese]

20. Correia, L.; Sena-Cruz, J.; Michels, J.; França, P.; Teixeira, T. (2015) “Comportamento de lajes pré-esforçadas.” 3º Seminário sobre o Projeto de Reforço de Estruturas de Betão com FRP’s (SPREB-FRP 2015), 18 September, University of Minho, Guimarães, 8 pp. [in Portuguese]

21. Coelho, M.; Caggiano, A.; Sena-Cruz, J.; Neves, L. (2015) “Comparação entre modelos constitutivos de interface: abordagem total versus abordagem com plasticidade.” 3º Seminário sobre o Projeto de Reforço de Estruturas de Betão com FRP’s (SPREB-FRP 2015), 18 September, University of Minho, Guimarães, 7 pp. [in Portuguese]

22. Fernandes, P.; Silva, P.; Correia, L.; Sena-Cruz, J. (2015) “Durabilidade de um adesivo epóxi e um laminado de CFRP expostos a distintas condições ambientais.” 3º Seminário sobre o Projeto de Reforço de Estruturas de Betão com FRP’s (SPREB-FRP 2015), 18 September, University of Minho, Guimarães, 8 pp. [in Portuguese]

23. Silva, P.; Sena-Cruz, J.; Azenha, M. (2015) “Efeitos da fluência num adesivo epóxi: investigação experimental.” 3º Seminário sobre o Projeto de Reforço de Estruturas de Betão com FRP’s (SPREB-FRP 2015), 18 September, University of Minho, Guimarães, 7 pp. [in Portuguese]


Reports

24. Silva, P.; Fernandes, P.; Sena-Cruz, J.M.; Barros, J.; Azenha, M.; (2014) “Efeito de fluência e durabilidade de elementos de betão reforçados de acordo com a técnica NSM” Relatório no. 14-DEC/E-41, Departamento de Engenharia Civil, Universidade do Minho, Guimarães, 24 pp.

- Seminar

- Publication of one book

- Publications in International and National Journals

- Publications in International and Nacional Conferences

- Oral presentations on Conferences

- Meeting of Technical Committees

- RepositóriUM

Top

back