TY - JOUR

T1 - Strengthening of a 19th-century roadway metallic bridge using nonprestressed bonded and prestressed unbonded CFRP plates

AU - Hosseini, Ardalan

AU - Ghafoori, Elyas

AU - Al-Mahaidi, Riadh

AU - Zhao, Xiao Ling

AU - Motavalli, Masoud

N1 - Funding Information: The authors acknowledge the financial support provided by the Australian Research Council (ARC) through a Linkage Grant (LP140100543), and the financial and technical support provided by the S&P Clever Reinforcement Company AG (Seewen, Switzerland) for the field application of the developed strengthening systems. Funding Information: The authors also gratefully acknowledge the support of Dr. Michel Barbezat from the Mechanical Systems Engineering Laboratory of Empa (Dübendorf, Switzerland) for performing the DMTA tests. Moreover, grateful thanks go to Matthias Wellauer, Dr. Abdollah Sadeghi Marzaleh, Slavko Tudor, Giovanni Saragoni, Dimitri Ott, Robert Widmann, and Hossein Heydarinouri from the Structural Engineering Research Laboratory of Empa (Dübendorf, Switzerland) for their assistance in performing the laboratory tests, and the preparation and shipment of the strengthening systems to Australia. The authors also acknowledge Prof. Alain Nussbaumer from the Resilient Steel Structures Laboratory (RESSLab), EPFL, for instructive scientific and technical discussions. Publisher Copyright: © 2019 Elsevier Ltd

PY - 2019/6/10

Y1 - 2019/6/10

N2 - This paper summarizes the strengthening of a historically significant 122-year-old roadway metallic bridge using nonprestressed bonded carbon fiber reinforced polymer (CFRP) plates. Prior to the bridge strengthening, sets of laboratory tests were conducted to characterize the mechanical properties, glass transition temperature, and CFRP-to-steel bond strength of two different epoxy adhesives (linear and nonlinear) commonly used for structural retrofitting. Furthermore, the field application complexity, as well as the short- and long-term efficiency of the developed nonprestressed bonded system, was compared with the existing flat prestressed unbonded retrofit (FPUR) system. Short-term measurements, including sets of truck-loading tests performed before and after strengthening, demonstrated that the tensile stresses were reduced by approximately 15% and 44% in the bridge cross-girders after strengthening by the proposed nonprestressed bonded and FPUR systems, respectively. The long-term measurement results, obtained from a wireless sensor network (WSN) system installed on the bridge, revealed that because of the mismatch of the steel-CFRP thermal expansion coefficient, diurnal temperature changes can cause significant thermal-induced stress cycles in the nonprestressed bonded CFRP plate. These diurnal cyclic stresses must be considered in the design of bonded CFRP strengthening solutions.

AB - This paper summarizes the strengthening of a historically significant 122-year-old roadway metallic bridge using nonprestressed bonded carbon fiber reinforced polymer (CFRP) plates. Prior to the bridge strengthening, sets of laboratory tests were conducted to characterize the mechanical properties, glass transition temperature, and CFRP-to-steel bond strength of two different epoxy adhesives (linear and nonlinear) commonly used for structural retrofitting. Furthermore, the field application complexity, as well as the short- and long-term efficiency of the developed nonprestressed bonded system, was compared with the existing flat prestressed unbonded retrofit (FPUR) system. Short-term measurements, including sets of truck-loading tests performed before and after strengthening, demonstrated that the tensile stresses were reduced by approximately 15% and 44% in the bridge cross-girders after strengthening by the proposed nonprestressed bonded and FPUR systems, respectively. The long-term measurement results, obtained from a wireless sensor network (WSN) system installed on the bridge, revealed that because of the mismatch of the steel-CFRP thermal expansion coefficient, diurnal temperature changes can cause significant thermal-induced stress cycles in the nonprestressed bonded CFRP plate. These diurnal cyclic stresses must be considered in the design of bonded CFRP strengthening solutions.

KW - Bond behavior

KW - Carbon fiber reinforced polymer

KW - Fatigue performance

KW - Mechanical anchorage

KW - Prestressed strengthening

KW - Steel structure

KW - Truck loading

KW - Wireless sensor network

UR - http://www.scopus.com/inward/record.url?scp=85062833434&partnerID=8YFLogxK

U2 - 10.1016/j.conbuildmat.2019.03.095

DO - 10.1016/j.conbuildmat.2019.03.095

M3 - Article

AN - SCOPUS:85062833434

VL - 209

SP - 240

EP - 259

JO - Construction and Building Materials

JF - Construction and Building Materials

SN - 0950-0618

ER -