Reaserch On Structural Performance And Design Methods Of Simply Supported-Continuous Carriageway Slab Without Prestress

With the development of expressway, the quantity of the bridge sharply increased, but the high speed of driving requires that the bridge has the fairly good continuous function.The expressway bridge with advanced level, most part of the small-span bridge (5 ~ 15meter) and the deck of bridge of spandrel arch bridge have adopt the consecutive bridge deck simple support structural system, these stuctures ubiquity diseases of driving discomfort and deck cracking. This article taking Fen-Shui-River Bridge for rely-on project, research using the method of simply supported-continuous without prestess to implement problems of carriageway slab continuously, doing some researches is followed as below:1. By relying on the detection of Fen-Shui-River Bridge, make the conclusion of insufficient stiffness for carriageway slab and compessive stress on the edge too much of their conclusions and analysis of its causes. For the exists problem in carriageway slab, several kinds treatment measures are proposed, compared by analysis, selected simply supported-continuous without prestess for final treatment measure.2. By the field test, proved that the stiffness of the carriageway slab had great improvement with simply supported-continuous treatment measure, but for the structure system of the small-span bridge, as we can not implement prestress in negative moment section, the problem of cracking in top surface still exsist.3. The load lateral distribution is the first problem in the structure design. According to simply supported-continuous system in this article, provided a load transverse distribution calculation through application of equal stiffness method; obtained the change rule of load transverse distribution along span direction; considered the influence of combined effect of deck pavement combined effect, and explored the considered cracks influenced calculated method.4. According to the top surface cracking of small span simply upported-continuous system without prestress, introducing fracture mechanical theory, adopted the measures of pasting FRP material on its top surface, analysis the measure effects influence of paste layer mumber and length, the conclusion is that this mesure can solve the problem of top surface cracing effectively.