基于相对转角与位移的空心板桥铰缝损伤识别

Damage Identification of Hinge Joints of Hollow Slab Bridges Based on Relative Angle and Displacement

针对现有空心板梁桥铰缝损伤的研究中,对传统铰缝理论在实际铰缝内部受力状态及传力机制分析不足的问题,在考虑剪切传递和侧向力基础上,建立弹簧铰缝的铰缝力学模型,推出铰缝损伤程度计算公式,代入相对挠度、剪力和相对转角,计算出铰缝损伤程度,定位损伤位置。研究发现,铰缝的受力状态较为复杂,因此若只考虑剪切传递并不完整,铰缝的侧向力也十分重要。依据既有铰接板理论,考虑铰缝的侧向力、损伤和变形,提出相应假设,建立铰缝力学模型和空心板桥计算模型。基于侧向力和剪切力产生的板梁相对转角和相对位移,建立了弹簧铰缝的力学模型,推出铰缝损伤程度的计算公式,并结合数值计算结果验证了理论模型的有效性,将相对挠度、剪力和相对转角代入公式,计算损伤程度,可有效发现铰缝损伤部位和计算损伤程度。结果表明,加载区域越接近损伤位置,损伤定位的精确性越显著,损伤程度识别结果的准确性越高。

In response to the existing research on hollow slab girder bridge hinge damage, the traditional hinge theory is not sufficient to analyze the internal force state and transmission mechanism of the actual hinge, and on the basis of considering shear transfer and lateral force, the hinge mechanics model of spring hinge was established, the hinge damage degree calculation formula was introduced, and the relative deflection, shear force and relative rotation angle were substituted to calculate the hinge damage degree and locate the damage location. It is found that the force state of the hinge joint is complex, so if only shear transfer is considered, it is not complete, and the lateral force of the hinge joint is also very important. Based on the existing articulated plate theory, the lateral force, damage and deformation of the hinge joint are considered, and corresponding assumptions are made to establish the hinge joint mechanics model and hollow slab bridge calculation model. Based on the relative turning angle and relative displacement of the plate and beam generated by lateral force and shear force, the mechanical model of spring hinge joint is established, and the formula for calculating the damage degree of hinge joint is introduced, and the validity of the theoretical model is verified by combining the numerical calculation results. The relative deflection, shear force and relative turning angle are substituted into the formula to calculate the damage degree, which can effectively find the damage area of hinge joint and calculate the damage degree. The results show that the closer the loading area is to the damage location, the more significant the accuracy of damage localization and the higher the accuracy of damage degree identification results.