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Northeast Extreme Tee (NEXT) beams have been recently developed for the accelerated bridge construction. The skew effect on live load distribution in a NEXT beam bridge, especially with integral abutments, is not clear and shall be assessed. In this paper, various skew NEXT beam bridges are evaluated through validated finite element (FE) analyses with solid brick elements. Parameters as studied include beam section, span length, and skew angle. Per AASHTO LRFD specifications, one- and two-lane loaded cases are examined to obtain the maximum tensile strains in beam stems under the design live loading (HL-93). Unskewed bridges are used as control specimens to compute skew reduction factors (SRF) for moment from the obtained FE strains. The FE- and LRFD-SRFs for moment are compared in terms of figures, which indicate the LRFD-SRFs have good agreements with the FE-SRFs at large. For the majority of the bridges, LRFD-SFRs govern the FE-SRFs. The research findings from this paper are useful for practicing engineers to safely design a skew NEXT beam bridge with integral abutments.

In order to resolve the steel corrosion problem in bridge decks, glass fiber reinforced polymer (GFRP) has been recommended as a substitute to the conventional steel reinforcement in bridge decks. However, the use of GFRP bars in bridge decks is still limited by several concerns, including the long-term durability of GFRP bars in the concrete under sustained loadings. Literature review showed that the tensile strength reduction of the GFRP bar should be governed by the sustained stress level in the GFRP bar. In this regard, a GFRP reinforced concrete deck was simulated in this paper, aiming to investigate the sustained stress levels in the GFRP bars through three dimensional finite element (FE) modeling. Per AASHTO LRFD specifications, one lane loaded and two lane loaded cases were examined to identify the maximum tensile strains in the internal GFRP bars subjected to dead loads and HL-93 design loadings. The FE results showed that the maximum tensile stresses in GFRP bars under service loads were less than 1% of the GFRP design strength, which implied that the GFRP bars could have excellent long-term performance in real concrete bridge decks.