Moisture diffusion and hygrothermal aging in pultruded fibre reinforced polymer composites of bridge decks

Abstract Gravimetric experimental studies were undertaken to characterise the moisture diffusion process in pultruded Fibre Reinforced Polymer (FRP) composites of bridge decks exposed to the vapour environmental aging condition as well as water immersed condition at temperatures of 20 °C and 40 °C respectively. After a short-term (250 days) aging duration, the moisture weight gain curves as a function of time were obtained. Comparing with the vapour conditions, FRP composites immersed in water resulted in much higher moisture uptake levels, around 3% of the initial self-weight. Based on the one-dimensional moisture diffusion theory, the moisture diffusion coefficients of FRP composites under different aging conditions were identified by the best least-square curve fitting to the experimental data. The obtained results indicated that high temperature can speed up the moisture diffusion rate, and the moisture equilibrium contents were mainly governed by the humidity of aging environment. Large portion of polymer relaxation was evident from the experimental data in the aging condition of 20 °C-water and 40 °C-water. Moisture desorption tests confirmed that, for the aging conditions of 40 °C-96% relative humidity (RH) and 40 °C-water, mass loss of FRP composites took place. No significant variations on moisture diffusion characteristic of FRP specimens from different parts of the bridge deck element can be drawn expect that, flange part specimens absorbed less moisture content than the two web parts.

[1]  Thiru Aravinthan,et al.  A review of optimization techniques used in the design of fibre composite structures for civil engineering applications , 2012 .

[2]  A Comparison of Laboratory-conditioned and Naturally-weathered Bonded Joints , 2001 .

[3]  A. Machida,et al.  Fiber-Reinforced Polymer Composites for Construction—State-of-the-Art Review , 2002 .

[4]  T. Keller,et al.  Investigation of 3D Moisture Diffusion Coefficients and Damage in a Pultruded E-glass/Polyester Structural Composite , 2009 .

[5]  Simon Collins,et al.  Advanced Composite Bridge Decking System—Project ASSET , 2002 .

[6]  B. Benmokrane,et al.  Environmental effects on glass fiber reinforced polypropylene thermoplastic composite laminate for structural applications , 2009 .

[7]  John Crank,et al.  The Mathematics Of Diffusion , 1956 .

[8]  A. Vautrin,et al.  A Novel Procedure for Identification of 3D Moisture Diffusion Parameters on Thick Composites: Theory, Validation and Experimental Results , 2002 .

[9]  Jan Knippers,et al.  Bridges with Glass Fibre–Reinforced Polymer Decks: The Road Bridge in Friedberg, Germany , 2010 .

[10]  Yixin Shao,et al.  DURABILITY OF FIBERGLASS COMPOSITE SHEET PILES IN WATER , 2002 .

[11]  S. Basavarajappa,et al.  Damage characterisation of glass/textile fabric polymer hybrid composites in sea water environment , 2010 .

[12]  J. Lim,et al.  Moisture absorption, tensile strength and microstructure evolution of short jute fiber/polylactide composite in hygrothermal environment , 2010 .

[13]  G. Marom,et al.  The anisotropic diffusion of water in Kevlar-epoxy composites , 1987 .

[14]  Ignaas Verpoest,et al.  Strength of Aramid-Epoxy Composites during Moisture Absorption , 1991 .

[15]  A. R. Berens,et al.  Diffusion and relaxation in glassy polymer powders: 2. Separation of diffusion and relaxation parameters , 1978 .

[16]  S. Shaw,et al.  The effect of environment on the fatigue of bonded composite joints. Part 1: testing and fractography , 2001 .

[17]  Arthur J. Helmicki,et al.  CLOSE LOOK AT CONSTRUCTION ISSUES AND PERFORMANCE OF FOUR FIBER-REINFORCED POLYMER COMPOSITE BRIDGE DECKS , 2004 .

[18]  R. Boukhili,et al.  Investigation of water absorption in pultruded composites containing fillers and low profile additives , 2007 .

[19]  S. M. Sapuan,et al.  Moisture absorption behavior of sugar palm fiber reinforced epoxy composites , 2008 .