Structural Performance Test of Long-placed Prestressed Box Girder under Design Load
In order to explore the structural performance of long-placed prestressed concrete box beams under the action of design loads,a batch of prestressed concrete box beams stored for more than two years in extreme weather conditions where the temperature difference between day and night exceeds 30℃were mostly used as research objects,and the appearance inspection and working per-formance strength inspection of the box beams were carried out in the way of sampling detection.The stress(strain)and deflection of the control section of the prestressed concrete box girder under the design load are measured.The results show that the longitudinal cracks of different lengths appear in the web of the box girder along the position of the prestressed steel bellows.The strength uniformity coeffi-cient Kbt is between 1.04 and 1.12,and the average strength uniformity coefficient Kbm is greater than 1.The variable calibration coeffi-cient ranges from 0.6 to 0.9,and the relative residual strain ranges from 2%to 17%.The overall sampling results show that the strength of concrete is in good condition.Under the test control load,the working performance is normal,and the bearing capacity meets the design requirements.
万方数据
维普
