Performance of CFRP posttensioned transverse grouted joints for full-depth precast concrete panels

摘要

One method employed in accelerated bridge construction is the use of full-depth precast concrete panels to construct new bridge decks or replace existing ones. The grouted transverse joint between precast concrete deck panels is one of the most vulnerable elements of the bridge deck. To extend the life of precast concrete bridge decks, it is imperative to improve the integrity of the grouted transverse joint. This paper compares the effect of low posttensioning stress on the initial joint cracking load, the peak load, and the overall behavior of precast concrete panels at a new female-to-female grouted transverse deck joint. Nine specimens with grouted transverse joints were tested monotonically to failure using an equivalent concentrated double-tire truck load. Three of the nine specimens had no posttensioning, three specimens were subjected to a 35 psi (240 kPa) posttensioning stress, and three were subjected to a 48 psi (330 kPa) posttensioning stress using carbon-fiber-reinforced polymer rods. Low posttensioning stress in the panel joint area increased both the initial joint cracking load and peak load capacity of the specimens and changed the failure mode from a bond failure of grout to concrete for the specimens without posttensioning to a tensile failure of the grout for the posttensioned specimens.