The anchor stress gauge outrange problems often happen in the in-situ monitoring work in large-scale water conservancy and hydropower project construction

and the reliability of data outrange is always be focused.Ultimate tensile test on three kinds of vibrating string stress gauge which range 210

310

400 MPa

is carried out respectively and working state under outrange ultimate stress state is studied.The results show that the curve of the load-displacement is linear within the range and the measurement readings before the anchor stress gauge yielded are reliable

but a rather big errors will occur if the load exceeds 1.6

2.0 times the measurement range.