盲孔法测量精度的研究─—边界及孔间距的影响

Effect of boundary and distance between holes on accuracy of blind hole technique

本文根据弹性力学柯西解及三维弹性有限元分析，对通孔及盲孔测量时，边界与孔中心距离和孔与孔间距问题进行了研究讨论，得到边界及孔间距是在一定范围内有影响的，孔与孔之间的影响与载荷方向有关，并且通过实验对其进行了验证。由此确定了误差小于２％～３％的横向最小间距ｄ＿（ｙｍｉｎ）（垂直于载荷）、纵向最小距Ｄ＿（ｘｍｉｎ）（平行于载荷方向）和孔与边界的最小距离ｄ＿（ｍｉｎ）。为盲孔测量获得比较可靠而又完整的应力数值提供了依据。

In present paper,the effect of distance from boundary to hole centerand hole to hole on the accuracy of blind-hole technique are discussed on the basis ofKirsch elastic solusion and solusion of 3D.F.E. calculation.Analysis shows that theboundary and distance between holes have effects to a certain content and moreoverthe effect of distanee between holes is related to direction of loading.Experimentsverifred the obtained analytical conclusions. Finally,the transverse and longitudinalminimum distance between noles d_(ymin) and d_(xmin) and the minimum distance from holeto boundary d_(min) are detemined. It provides necessary basis for obtaining accurate andreliable stress value with blind-hole method.