Abstract: In order to study the failure displacement criterion of shallow-buried vertically loaded anchors(VLA) in soft clay, displacement-controlled and load-controlled static loading model tests are conducted by using an electric servo loading apparatus developed by the authors. The embedment depth of vertically loaded anchors is 3 times of the plate width and the acute angle between the plate and horizontal line is 30°. The normalized curve is obtained by normalizing the normal load and displacement based on the ultimate bearing capacity and width of the anchor plate; then, the failure displacement criterion of the vertically loaded anchor can be determined according to that. The model test results show that the failure displacement is about 0.38 times the width of anchor plate when the anchor failure occurs. Besides, on the basis of the size of anchor plate, the burial depth and the strength of soil for tests, the ultimate bearing capacity of anchor is calculated by using the empirical formula. It turned out that the ultimate bearing capacity of vertically loaded anchors determined according to the failure displacement criterion is nearly identical to the value determined based on the empirical formula. The difference between them is less than 10%. The rationality of the failure displacement criterion is verified by the comparison.

Key words: soft clay, vertically loaded plate anchors(VLA), model test, displacement failure criterion