Experimental Research On Concrete Shrinkage And Creep Of Large Span Continuous Rigid Frame Bridge

Large span prestressed concrete continuous rigid frame bridge due to the structural response caused by shrinkage and creep of concrete,especially mid span deflection,which is a subject of research and experiment in bridge engineering,also achieve fruitful results,but due to the influence of concrete materials,bridge structure and stress,bridge site environment,research conclusion still exist differences.This paper relies on Prefecture of Yunnan Honghe Shiping to Yuanjiang Expressway 3 contract Xintian section babaoshu long-span continuous rigid frame bridge(bridge 90m+160m+160m +90m),through at the scene to carry out the standard test,a three span continuous rigid frame model,model of a simply supported beam,bridge construction monitoring means,long-span continuous rigid frame bridge site concrete shrinkage and creep experimental study,comparing the results of the analyzing results based on the measured data and the prediction model,obtained the following main conclusions:(1)The standard specimen shrinkage strain measured value and JTJ 023-85 model before 60 days the results are in good agreement,and in age of 190 days,the calculated values of the model are larger 19.4% than the measured shrinkage strain value;standard test pieces of creep coefficient measured values and JTG D62-04 model before a month are in good agreement,and in age of 190 days,the calculated values of the model are larger 27.3% than the measured creep coefficient.(2)In the three span continuous rigid frame model,the measured values of the displacements are in good agreement with the calculated results by using the JTG D62-04 model,and the relative deviation between the calculated values of the model and the measured shrinkage creep coefficient is only 0.1% after loading for 250 days.(3)In simple supported beam model,the measured values of the span in the span are in agreement with the calculated results by using JTG D62-04 model,and after loading for 250 days,the calculated values of the model are larger 6.5% than the measured shrinkage creep coefficient.(4)Combined with the data analysis of standard specimens,continuous rigid frame model and simple supported beam model,the JTG D62-04 shrinkage and creep model is suitable for this bridge.(5)Predicted deflection displacement of real bridge girder caused by shrinkage and creep with JTG D62-04 model,and after 1 year the maximum deflection displacement of this bridge main span is 5.87 mm,after 2 years is 9.00 mm,after 3 years is 11.39 mm,after 5 years is 14.91 mm,after 10 years is 20.21 mm.