Assessing Code Live-Load Models for Bridge Substructures
The present paper examines the effectiveness of code live-load models in accurately estimating vehicular loads on bridge substructures. The study utilizes realistic traffic vehicle data from four Weigh-in-Motion databases, which provide an authentic representation of vehicle information. This ensures that the examination of the bridges studied is based on real-world data.
The evaluation includes various bridge models, ranging from single-span girder bridges to two-, three-, and four-span continuous pinned-support girder bridges. By comparing the extreme force values obtained from the Weigh-in-Motion databases with those predicted by selected code live-load models, the study assesses the accuracy of the models.
The exceedance rates, which indicate the frequency with which the predicted forces exceed the actual forces, are presented in a spectra format, organized by span length. The analysis reveals significant variations in these exceedance rates, underscoring the need for improvements in code live-load models to achieve more accurate estimations of the forces transferred to bridge substructures.
Enhancing the accuracy of these models is crucial in achieving more consistent reliability levels for a range of limit states, such as resistance, fatigue, serviceability, and cracking. By refining code live-load models, engineers and policymakers can ensure that bridges are designed to withstand the actual loads they will experience, leading to improved bridge safety and longevity.