Impact Analysis Of Static Load Test Calibration Coefficient On Pavement And Guardrail Of Beam Bridge

This paper takes 4 pieces of prestressed.T girder bridge(span 35 m,width 8m)and 6 pieces of prestressed hollow slab(span 20 m,width 8m)as an example,with the aid of the finite element software MIDAS to establish grillage model,through the analysis of the result of loading test and through analyzing the influence of deck pavement and the guardrail on two kinds of bridges,the following four models were established: model 1 considering 10 cm concrete now poured layer structure involved in the force,model 2 the pavement layer as external loads applied to establish model 3considering the guardrail in structure stress,and in the last model the guardrail as external load was applied to simulate.Based on the experimental data and the theoretical analysis of these models,the following conclusions are drawn:(1)The strain calibration coefficient of model 1(span 20 m,width 8m,6 pieces of prestressed hollow slab bridge)is 0.72~0.78,and deflection calibration coefficient is0.90~0.95,compared with model 2 and model 4,the calculated value of model 1 is closer to the measured value and to the actual structure.Besides,the calibration factor of model 3 of beam and plate is greater than 1.Therefore,the modeling of model 1 is optimal.(2)The strain calibration coefficient of model 1(span 35 m,width 8m,4 pieces of prestressed T girder bridge)is 0.74~0.91,deflection calibration coefficient is 0.82~0.94,compared with model 2 and model 4,the calculated value of model 1 is closer to the measured value and to the actual structure.Besides,the calibration factor of model3 of beam and plate is greater than model 1,therefore,the modeling of model 1 is optimal.(3)Through the analysis between seven hollow slab bridges(width 9.25m)and eight hollow slab bridges(width 10.5m),the author found that the change trend of calibratio n coefficient of these two types of bridge widths is basically the same as that of six hollow slab bridge with width 8.(4)Through the analysis between 5 prestressed T girder bridge(width 10.06m)and 6prestressed T girder bridge,(width 12.12m),the author found the variation trend of calibration coefficient of these two types above is basically the same as that of 4prestressed T girder bridge with width 8m.(5)considering the fact that crash barriers are all involved in model 3 and its calibration coefficient of deflection and strain is mostly more than 1.0,so this modeling approach can not be used in model 3.