Abstract: Based on the similarity ratios of simulated model to the prototype in elastic and plastoelastic stages, the loading behaviors of the simulated model are back analyzed to the prototype for the reinforced aqueduct with multi-longitudinal beams. Utilizing the three dimensional nonlinear finite element method, the bearing properties of the prototype reinforced concrete aqueduct are calculated under gravity load, water loads at design level and checking level. The calculation results are compared with the back analysis. The accuracy of the simulated model is demonstrated including the cracking load, stresses of longitudinal-horizontal beams and the side wall, the aqueduct vertical displacements and support counter-forces. The simulated model can be used to evaluate the normal service behaviors of the prototype aqueduct after back analysis.