Research On Rational Reinforced Approach Pavements Length Of Jointless Bridges

The jointless bridge approach pavement is a pre-cutting pavement. Thepavement connects approach slab, main girder and bridge together without any joints.This kind of structure eliminates not only all the expansion deck joints, but also thejoints between bridge and approach road. Reinforced approach pavement as ajointless bridge structure system to absorb the main beam deformation, the length anddurability of the pavement pay a important part in the jointless bridge system. Whentemperature drops, the approach moves with the main girder and approach slab, thecracks in the weak pre-cutting-sections are developed and the jointless bridgestructure system uses those cracks developed at the approach pavement to absorb thebridge contraction displacement, which is the worst stress state to the pavement. Themechanical performance of the reinforced approach pavements is influenced bycontraction distortion of the main beam, shrinkage and layer friction. This papermainly focuses on the mechanical performance analysis of pavement. On the basis oftheoretical analysis, the length calculation method of reinforced approach pavementand design method of the anchoring ground beam is put forward. The main researchworks are done as follow:(1)The paper summarizes the interlayer sliding friction resistance distributionforms of approach pavement slab, combines with the interior sliding test to determinethe inter-layer sliding the interfacial shear stress-slip displacement relationship, andprovides theoretical data reference for approach pavement analysis; The stress anddisplacement solution of the reinforced approach pavement has been deducedaccording to the linear constitutive bond-slip relation between the reinforcement steeland concrete, the friction forces and the anchor forces.(2)The working mechanism of the reinforced approach pavement anchoringbeam has been studied. The displacement of anchoring ground beam under levelforces is calculated by matrix displacement method. The parameter values ofanchorage ground beam are analyzed. The end anchorage ground beam of reinforcedapproach pavement design is given.(3)The length and reinforcement calculation method of reinforced approachpavement has been put forward based on the theoretical analysis and anchor beam.The program of the reinforced approach pavement has been complied by fortran language, which can calculate pavement length automatically. Influencing factors,such as longitudinal reinforcement ratio, interfacial friction coefficient and slabthickness are analyzed to evaluate their effects on the length of approach pavement.The conclusions obtained from this work may be benefit to optimize the length ofapproach pavement and improve the overall stability and durability of the approachpavement structure.(4)The ANSYS software has been used to simulate a real construction project.The performance indicators of the reinforced approach pavement are analyzed. Acomparison is made between the finite element numerical solution and exactsolution.The Results show that the length and reinforced calculation method aresecurity. It can apply to the reinforced approach pavement length estimate calculation.