Title: Durability Assessment of Combined Environmental Exposure and Bending

Author(s): C. Helbling and V.M. Karbhari

Publication: Symposium Paper

Volume: 230

Issue:

Appears on pages(s): 1397-1418

Keywords: durability; e-glass; hygrothermal; sustained strain;vinylester; water

DOI: 10.14359/14900

Date: 10/1/2005

Abstract:
Although fiber reinforced polymer (FRP) composites are increasingly beingused in civil infrastructure applications, there is still a lack of well documented data andunderstanding regarding their long-term performance especially under combinedexposure to environmental conditions and sustained load. This paper presents theresults of an investigation into synergistic effects of hygrothermal exposure andsustained strain on pultruded E-glass/vinylester composites. It is seen that effects ofincreasing strain levels can be significant and can lead to changes in damagemechanisms, especially in conjunction with moisture uptake. High strains incombination with moderate to elevated temperatures resulted in substantially morecatastrophic failure than elevated temperatures in combination with lower strains.These effects were noted in tension and short-beam-shear modes, and overalldeterioration was corroborated by moisture uptake, Dynamic Mechanical ThermalAnalysis (DMTA) and Fourier Transform Infrared Spectroscopy (FTIR) investigations.