| 摘要 |
The invention concerns a method which consists in producing on either side of a crack (6), initiated at the top of a notch (5), at least two through holes (3) in the width (B) of the specimen (4); projecting part of one or several homogeneous incident light beams (1) through said holes (3) whereof each displacement simultaneous with the opening of the crack (6) lips is measured by means of biaxial planar photodetectors (8). Said measuring method is independent of the type and velocity of loads exerted on the specimen and of the temperature thereof. |
