DURABILITY OF ARAMID FIBER REINFORCED PLASTIC PRETENSIONED ELEMENTS UNDER TIDAL/THERMAL CYCLES

This paper presents results from a 33-month exposure study to assess the likely effect of diurnal/seasonal temperature change on the durability of aramid fiber reinforced plastic (AFRP) pretensioned piles driven in tidal waters. The aramid fiber composite ARAPREE was used in the investigation. Twelve precracked AFRP pretensioned beams, designed to fail by rupture of the prestressing rods, were placed outdoors in two saltwater tanks. The beams were simultaneously exposed to wet/dry cycles (simulating tides) and hot/cold cycles (simulating temperature variation). The effect of exposure was evaluated from bending tests conducted periodically over the nearly 3-year exposure period. The results showed that exposure led to visible cracking and a rapid deterioration in bond. Accompanying strength reductions ranged from 43% to 55% in specimens exposed for more than 21 months (15,500 hr). This provides persuasive evidence of the unsuitability of AFRP as a pretensioning element for piles driven in tidal waters. Two-dimensional finite element analysis indicated that moisture absorption by the AFRP rods had been more important than temperature change for the bond degradation observed in the study.

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  • English

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  • Accession Number: 00762791
  • Record Type: Publication
  • Contract Numbers: 2901090/F
  • Files: TRIS
  • Created Date: Apr 17 1999 12:00AM