| With the rapid development of the transportion in our country, long-span continuouspre-stressed concrete beam and continuous rigid frame bridges were used in highway whichacross rivers, lakes, deep groove canyon. because of its easily building, beautiful appearanceand economical. However, these type of bridges had the defect of continuous downwarping inmidspan which may cause cracking of concrete and bridge damage.The studies in recent yearsshow that，the creep of concrete has a direct impact on the linear and internal forces ofbridges of these type，how to evaluate and forecast the effect of on the structure correctly hasthe vital significance to guide the engineering design and constructionThis article finite the element model of a large long-span continuous girder bridge withMIDAS/Civil build bar system，then analyes the effects of creep of concrete on large spancontinuous girder bridge, at last expound the mutual effect of pre-stress loss and the beambody cracking under the creep.The article compares and analyes the creep of different patternsreferring to the standard of JTGD62-2004，then analyes the concrete creep effect of thedifferent time, different humidity and different countries standard the temperature andcracking.The calculation result shows that： it is relatively safe to select JTGD62-2004tobuild the concrete creep model； creep effect is increased along with the growth of the timeand the rate is fast after a slow first and at last it is leveing off. After10years the deflectionand deformation under the creep is basically completed, the humidity, the greater the concretecreep effect on the bridge； The temperature gradient mode of UK has a great difference withthe JTGD62-2004，the opposite is the rail specification； Compared with the cracking ofpre-stressed concrete box girder structure，crack deflection and stress of the girder after allshowed a trend of growth and the stress of the pres-tressed reinforcement increased afterdecreased。... |
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