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

In present paper,the effect of distance from boundary to hole center and hole to hole on the accuracy of blind-hole technique are discussed on the basis of Kirsch elastic solusion and solusion of 3D.F.E. calculation.Analysis shows that the boundary and distance between holes have effects to a certain content and moreover the effect of distanee between holes is related to direction of loading.Experiments verifred the obtained analytical conclusions. Finally,the transverse and longitudinal minimum distance between noles d_min and d_min and the minimum distance from hole to boundary d_min are detemined. It provides necessary basis for obtaining accurate and reliable stress value with blind-hole method.