EXAMINATION OF BRIDGE LIVE LOAD MODEL IN KOREA

Recently it has been reported in many countries, including Korea, that bridges have been seriously damaged due to the increasing volume of overloaded vehicles. Since the safety of bridges is highly related to the design load level and extreme effects induced by traffic loads during their lifetime, it is important to determine the design live load to properly represent the load effect of the current truck traffic. The live load depends on many parameters of truck and traffic characteristics. The objective of this study was to calculate the maximum effect of truck loadings based on the survey data collected, and to evaluate the current live load model in Korean Bridge Design Code. Several citation data were collected and two cases were considered: single truck and two trucks on the bridge. The maximum live load effects for simple span and two equal continuous span bridges were calculated. As a result of this study, the effect of live load models in the current design code is relatively low at very short spans and medium spans (about 40-50m). Also, results show similar trends as the new live load model in AASHTO.