基于特征参数的栓接结合部螺栓预紧力评估

Evaluation of bolted joints tightening force based on characteristic parameters

为了解决频响函数法在栓接结合部特征参数辨识中的不适定性问题及期望通过定量评估螺栓预紧力以评估栓接结合部损伤程度,采用正问题求解思路,提出依据动力方程定义参数辨识的目标函数并利用特征参数定量计算螺栓预紧力的评估方法。建立栓接结合部等效线性模型,通过模态试验测量不同预紧力下的结构频响函数;构建目标函数,采用粒子群优化算法获取不同预紧力下的特征参数,并通过多项式拟合特征参数与预紧力之间的关系曲线,从而评估螺栓预紧力;通过数值仿真和试验验证方法的有效性和适用性。研究结果表明:所提方法能够准确辨识结合部参数,利用拟合的关系曲线可以准确地定量评估螺栓预紧力。

In order to solve the ill-posed problem in characteristic parameters identification of bolted joints,the positive problem solving idea was adopted that an objective function was proposed for parameters identification based on the dynamic equations.In addition,the characteristic parameters were used to evaluate the bolt tightening force quantitatively.Firstly,the linear model of bolted joint was constructed and frequency response functions under different bolt tightening force were measured in model test.After obtaining the objective function,the particle swarm algorithm was used to identify the characteristic parameters under different bolt tightening force.The fitting curve for characteristic parameters and bolt tightening force was obtained and used to evaluate the bolt tightening force quantitatively.Finally,the validity and applicability of proposed method was verified by a series of numerical simulations and experimental studies.The illustrated results show that the proposed method can identify parameters accurately,and the fitting curve can be used to evaluate the bolt tightening force reliably.