Basic Performance And Engineering Application Of Two Types Of Semi-Integral Abutment Jointless Bridges

The abutment and the main beam of the jointless bridges in Canada was relatively independent,which keeping the characteristics of conventional joint bridges in the maximal degree,the swell-shrinking deformation of main beam under temperature was transferred to approach pavement,this type of bridge has such features as clarity of compressive stress and deformation,simple structure,convenient construction and maintenance,this jointless bridges were commonly used in western countries?The pavement joint was ulteriorly cancelled in the new full jointless bridge with semi-integral abutment,the swell-shrinking deformation of main beam under temperature was absorbed by the continuous reinforced concrete pavement with pre-cutting crack,setting of pre-cutting crack can control the location and width of cracks,prevent the production of reflection crack in asphalt surface,durability and bearing capacity of continuous reinforced concrete pavement was ensured,the jointless bridge was realized in real meaning?Relying on Science and Technology Project of"Study on design and construction technology of semi-integral jointless bridge" in Yunnan,this paper made a systematic exposition of basic performance and engineering application of this two jointless bridges with semi-integral abutment by theoretical calculation analysis,test room study and practical application on the relying bridges,The main research contents are as follows:1?On the Basis of investigation of application and development of the jointless bridges in the world and the research and practice of our country,application research on the introduction of semi integral bridge in Canada,use continuous reinforced concrete pavement to allow the characteristics of the work with cracks,we develop a new type of semi-integral full jointless bridge structure system?2?Through the test in model test and full-scale model test,we study the development of continuous reinforced concrete pavement crack under active crack control,put forward countermeasures to prevent and control reflective cracking?3?By analyzing force performance of key structure include main girder,approach slab,continuous reinforced concrete slab and abutment etc,under the effect of the temperature fluctuation and the concrete shrinkage and creep,we present the design principles and calculation methods of two types of semi integral jointless bridges,For example,the calculation of beam pressure calculation,expansion joint width between road and bridge,continuous reinforced concrete pavement length and reinforcement calculation etc?4?Through the implementation of the test bridge,we present Design and construction key technology of main structure include main girder,approach slab,abutment drainage,expansion joint width between road and bridge,continuous reinforced concrete slab and base course etc?5?By burying earth pressure box,steel string strain sensor,displacement observation point in the main girder and approach slab,We are continuously monitoring the longitudinal displacement of the main girder,backfill settlement,Strain of approach slab,earth pressure at the end of the main girder,provide data support for the evaluation of the test bridge?Based on test bridge operation state and monitoring data,The monitoring results show that the behaviour of this two kinds of jointless bridges with semi-integral abutment is normal,the appearance of main beam,bridge pier and bearing was perfect,no crack was found,the structur was safe and reliable?From the application effect,his two kinds of jointless bridges can ensure smooth ride,driving comfort,especially in the new full jointless bridge with semi-integral abutment,vehicle jumping phenomenon at bridge abutment was completely eliminated,expected targe was completely reached !...