Prestressed Concrete Continuous Rigid Framebridge Stress Monitoring And Prestressinglosses

In this paper, a prestressed concrete continuous rigid frame bridge as the engineering background to detailed stress monitoring methods in monitoring stress, respectively by Midas FEA and Midas civil to establish the finite element model and finite element model analysis simulation of bridge, and using Midas FEA to calculate theoretical stress. Combined with the actual stress monitoring process and theoretical analysis, makes a detailed analysis on the stress error caused by test instrument, temperature, shrinkage and creep, hydration heat, concrete condensation, shear lag effect, monitoring method.Applicating method of stress analysis to practical engineering stress monitoring results to verify the correctness of the method. The experimental study on prestress loss of longitudinal prestressed anchor postat the construction site, the measured loss of prestress anchoring steel beam with different forms, different steel length and different tensioning anchorage velocity values. Experimental study on the twisting process of anchorage prestress loss of vertical prestress anchoring at three kinds of arrangement of not set the plate, cone plate and flat plate on the sensor. Screw torque values, set the layout of the form of cone plate anchorage prestress loss maximum. The screw torque under different values of prestress losses of experiment is conducted. When the main reason of anchorage prestress loss value decreases with thescrew torque value increases is that enlarge the screw torque can effectively reduce the tendon retraction, rather than increase additional prestressed. Through the experimental study, combined with the situation of construction site, reasonable screw torque values are given.