盲孔法检测钢结构工作应力研究

RESEARCH ON WORKING STRESS OF STEEL STRUCTURES BY HOLE-DRILLING METHOD

通过有限元方法对盲孔法释放系数A、B进行标定,并与轴心受拉下标定试验的结果进行对比验证。结果表明:对于轴心受拉构件,使用盲孔法进行工作应力的检测是可行的;有限元标定得到的释放系数A、B在低应力状态下与实测值吻合较好;对于高应力状态下的孔边塑性应变引发的误差,可根据形状改变比能参量S与释放系数A、B的关系进行修正;对于加载状态下钻孔时产生的切削加工应变,可根据试验测得的切削加工应变与释放应变的关系进行修正。

The finite element method was used to calibrate the release coefficient A and B of the hole-drilling method,and the results were compared with the test results under axial tension load.The results showed that it was feasible to use hole-drilling method to detect the working stress of axial tension member.The release coefficient A and B obtained by finite element calibration were in good agreement with the measured value under low stress state.The error caused by the plastic strain on the hole edge under high stress state could be modified according to the relationship between the distortion-energy parameter S and the release coefficient A and B.The cutting strain produced by drilling under loading state could be modified according to the measured relationship between the cutting strain and the released strain.