Analysis Of Response And Vehicle Weight Limit Of Fabricated Box Girder Bridge Based On Monitoring Data

It is of great importance to develop a reasonable vehicle weight limit for the safeoperation and durability of the bridge, because extra heavy trucks frequently traveling damagethe bridge structure performance and durability severely. Based on long-term traffic loadmonitoring data, this paper calculated the response of five prestressed concrete continuousbox girder bridges. Then selects five types of vehicle models, analyze the load limit under thedesign load and ultimate capacity state. The major researches are as follows:Firstly, extract traffic cases that have a great impact on the bridge structure from actualtraffic flow data recorded by the WIM system, the characteristics of the extra heavy truckcases and the vehicle traveling lane, weight, length, speed is studied.Secondly, take the fabricated box girder bridges common in highway as the object,discusses grillage method modeling features, and establishes several fabricated concretecontinuous box girder bridges that have different spans. Using the random traffic-bridgecoupled vibration analysis software calculates the DAFs and actual spatial effect of the boxgirder bridges under extra heavy truck cases, then compares with the bridges’ responses underdesign specifications loads.Finally, combined with the characteristics of the real vehicle type distribution, selectsseveral typical vehicles as overloading transport models. Using the whole vehicle loadedfunction of the random traffic-bridge coupled analysis software, three loading method isstudied, a single heavy truck loaded on overtaking lane and carriageway respectively, and twoheavy trucks loaded side by side on both lane. The vehicle weight when two heavy trucksloaded side by side on the bridge that induce the similar response to design load could beregard as the limit weight reference.