Experimental Study And Numerical Simulation On Bearing Capacity Model Of Modular Reinforced Soil Abutment

Geosynthetic reinforced soil(GRS)bridge abutment is widely used in foreign countries,but it is just in the initial stage in China.And its deformation and bearing capacity under static work are more critical.This paper takes modular GRS bridge abutment project as the research object,and relies on the project of China Earthquake Bureau "Full-height rigid facing wall reinforced abutment design theory research"(XH204402)to design and complete the static test of large GRS bridge abutment.The deformation and bearing capacity performance were studied through a combination of experiments and numerical simulations,and the main work and results are as follows:(1)According to the large similarity ratio of 1:2,the similarity relationship of the main physical quantities of the GRS bridge abutment model was deduced through the three basic dimensions and dimensional analysis method.And a three-dimensional test model of the bearing capacity of GRS bridge abutment was designed.The mechanical properties of materials are introduced.The sensor layout and calibration methods are introduced.The preparation work of model test is introduced.The experimental loading scheme and termination conditions are introduced.(2)To carry out model tests on the bearing capacity of GRS bridge abutment and describe the phenomenon of the test model;The deformation laws of the top settlement,the horizontal displacement of the front wall and the soil displacement are analyzed and the relevant data are compared.The law of vertical earth pressure and horizontal earth pressure behind substructure slab of abutment is studied and compared with FHWA.The strain distribution law of geogrid is studied.By comparing the experimental data with the theory,the calculation method of predicting the maximum lateral displacement and the axial force of steel bars is evaluated.(3)FLAC 3D numerical simulation was used to model the test model to verify the accuracy of numerical simulation and analyze the influencing factors of abutment top settlement and horizontal displacement deformation;The potential fracture surface trend in X and Y directions of GRS bridge abutment is introduced,and the influencing factors are analyzed.(4)According to the numerical simulation results of ultimate bearing capacity obtained from the code,the influencing factors of ultimate bearing capacity are studied;The standard calculation method of bearing capacity is evaluated.