Skip to content

Axial pullout resistance of reinforcements embedded in fill materials is an important property in the design of mechanically stabilized earth walls. Commonly, minimum of three pullout tests are performed to develop the pullout factors considering the different levels of overburden stresses acting on the reinforcement. Pullout tests involve large-scale testing and performance of these tests is time consuming as well as sample preparation is labour intensive. Accordingly, in the present study, a staged pullout test is conducted on a smooth-metal- strip reinforcement embedded in sand and compared with conventional pullout test results. A large-size (0.9 m in length x 0.9 m in width x 0.6 m in depth) pullout box is used in the study, and normal stresses equivalent to 1 m, 3 m and 5 m overburden of sand at the reinforcement level are applied. The results of staged pullout testing on smooth metal strip embedded in sand are found to be in close agreement with the conventional pullout tests under the normal stresses considered in the study. Pullout resistance factors derived from conventional and staged pullout test results are presented in the study. Based on extensive pullout studies conducted in the study, it is found that staged pullout testing of metal-strip reinforcement placed in granular fill can be an alternative to conventional pullout tests performed on samples subjected to different normal stresses.