Study On The Decay Of Load Transfer On Cement Concrete Pavement

Joints are the important part of cement concrete pavement, but also are the weak positonof cement concrete pavement. Load Transfer Capacity of the joints have a greater impact onthe performance and service life of the Cement Concrete pavement.There are some maindiseases caused by joints,such as pumping,cavity,slab corner crack. These diseases can lead tothe load transfer capacity of joints reduce, and serious influence the use situation of thepavement. Therefore,the decay rule of load transfer capacity of joints under the couplingeffect of the load and temperature is deeply studied,which has the important practicalsignificance.Through the load transfer capacity of joints of concrete pavement investigation,andconcludes that the load transfer capacity are increased as the base stiffness.The load transfercapacity of poor cement concrete base is better than the cement stable macadam,the last is ashstabilized gravel.According to research the mechanism of load transfer capacity of different types ofjoints,the dowel bar diameter,the dowel bar length,slab thickness and the foundation modulusare analyzed,draw a conclusion that the load transfer capacity is determined by the loosenedquantity.Using the finite element software to create three-dimensional joint model,analayzing thestress distribution of concrete around the dowel bar in different situations,and the influence ofloosened quantity for the concrete stress around the dowel bar.The conclusions are that thereduce of load transfer capacity is not caused by the transformation of dowel bar,but becauseof concrete became fatigue damage around the dowel bar.According to make fatigue loading test to the specimens of dowel bar, different factorson the effect of load transfer capacity are analyzed,and summarizing the decay rule of loadtransfer capacity. Regression the relationship between the number of loads and load transfercapacity of joints.