【摘要】 为确保钢结构工程的可靠性和安全性,必须严格控制连接螺栓的预紧力,必要时还要在线监测螺栓工作应力。依据声弹性原理,提出了利用高强度螺栓轴向应力与拧紧前后超声波渡越时间差的关系,结合螺栓材料系数、夹紧厚度等参数,间接检测螺栓轴向应力的方法。克服了耦合层厚度的离散以及温度变化造成的测量误差,大幅度提高了应力的测量精度。在此基础上,提出了材料系数预测、校正的方法。精度分析结果表明,螺栓应力测量精度优于5％,可满足绝大多数工业现场的要求。更多还原

【Abstract】 To guarantee the reliability and security of the steel construction, the clamp load of the joint bolt should be under strict control, sometimes even the tension of the bolt should be measured on-line. Referring to the sonic elasticity principles, an indirect method is proposed for bolt tension measurement, based on the relation between the axial tension of high strength bolt and the time difference for the echo to return from the opposite end before and after the bolt is tightened. This method also takes the material factors and the clamp length into account. The method achieves high accuracy measurement by removing the measuring error caused by the discreteness of the thickness of the couplant and change in temperature. Based on the method, a new way on forecasting and revising the material factors is brought forward. The accuracy in bolt tension measurement is proved to be better than five percent, and thus is acceptable in most of the industry use.更多还原