Review on Extreme Extrapolation Methods for Bridge Traffic Load Response

Abstract:

Extreme extrapolation methods are critical to predict the extreme value of long-term load response on the base of traffic data acquired in a short time. In this paper, a review on the extreme extrapolation methods in the fields of traffic load research is presented. Several main extrapolation methods are introduced in current applications. Analysis on the key parameters, including basic data and bottom distribution, is performed with consideration to their influence on extrapolated extreme values. A detailed comparison between empirical extrapolation method and maximum extrapolation method is also provided. The research results suggest that the key of extreme extrapolation of traffic load response is the description of tail data tendency of the bottom distribution. Length of the measured data which would be adopted for extreme extrapolation should be at least 21 days to provide a reliable reflection on the practical situations. The empirical extrapolation method is credible in a way when the reliability standard problem is answered. The maximum extrapolation method is very accurate and efficient under the circumstance of basic data with large capacity. The extrapolation method based on level crossing method not only needs to search for the optimum fitting starting point, interval and goodness-of-fit test method, but also significantly depends on the selection of empirical distribution including Rick Formula.