Title: Reliability analyses of interface shear transfer in AASHTO LRFD specifications model and an alternative model
Date Published: September - October 2018
Volume: 63
Issue: 5
Page Numbers: 36 - 50
Authors: Mahmoodreza Solrani
https://doi.org/10.15554/pcij63.5-03
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Abstract
Interface shear transfer (IST) is a concept that describes the mechanisms by which shear forces pass through a concrete-to-concrete interface where no, or negligible, moment is present. Previous research has shown that the IST model of the 2014 American Association of State Highway and Transportation Officials’ AASHTO LRFD Bridge Design Specifications produces inconsistent levels of accuracy for different values of design variables, such as compressive strength of concrete. In this study, a reliability analysis was performed on the AASHTO LRFD specifications model to evaluate the code’s resistance factor. In addition, a comparative reliability analysis was performed on a new IST model that improves the limitations of the AASHTO LRFD specifications model to calibrate its resistance factor to meet the target reliability index of 3.50. Results showed that for a critical load combination, the reliability indices of the AASHTO LRFD specifications model with normalweight and lightweight concrete were 2.80 and 5.38, respectively, whereas applying a resistance factor of 0.95, the reliability indices of the alternative IST model for tests with normalweight concrete and lightweight concrete were 3.56 and 4.11, respectively. The results of the reliability study show that the alternative model performs better than the AASHTO LRFD specifications model. In this study, reliability indices were also scrutinized for different ranges of IST design variables, which benefits designers and practitioners.
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