The Internal Force Calculation Method Research Of The Semi-Integral Abutment Bridge’s Slab

For joint bridge, the slab of the bridge is an one-way slab which is supported on the abutment bracket and the corbel.The internal force calculation method is that simplifing slab into simply supported beam or elastic foundation beam. But for the Semi-Integral abutment bridge,the girder is linked with the slab,which will be influenced by the gider’s expansion and the beam-end’s deformation.The slab of the Semi-Integral abutment bridge is also beared the load which is transferred by the girder while it is bearing the vertical load provided by the cars and the gravity.The load aspects,level and if the existing design method of the slab still available while considering the slab-end’s load is a worthful subject to exploring.First,we should verify the adaptation of the existing internal force calculation method of the slab.Simulating the joint of the girder and the slab by the finite element software ABAQUS and then apply the slab-end with moment,shear force and axial force,operate model and get the calculation result. Analysis the calculation result and get that the slab-end axial force is the most important factor which affect the slab’s internal force calculation.After then,set up the entity model and operate it with different parameters, which is associated with the influence degree of the slab’s internal force calculation.Then,we get that the existing internal force calculation method is not adapted in the Semi-Integral abutment bridge.Then,based on the simply-supported beam method and put forward Modified simply-supported beam method which is appropriated for the Semi-Integral abutment bridge.The Modified simply-supported beam method consider the actual force environment by two modified coefficient α and β.And they replace respectively the supporting role of the foundation soil and the influence of the axial force.At last,multiply α and β,get the comprehensive modified coefficient y. In the slab’s internal force calculation of the Semi-Integral abutment bridge,we just multiply the comprehensive modified coefficient y with the length of the slab,get the calculated length and operate with the calculated length by the simply-supported beam method.Finally,comparing the theoretical value and the finite element value to prove the correctness of the Modified Simply-supported beam method.In addition,build the slab model with the simply-supported beam method,elastic foundation beam method and modified simply-supported beam method respectively,calculate and get the result. Analysis the results and compare the advantages and disadvantages of the three calculation methods.Then we get the result:In the three internal force calculation method of the slab,the Modified simply-supported beam method is the most available for the Semi-Integral abutment bridge area.