Abstract: A novel method for constructing kinematically admissible velocity fields in the upper bound limit analysis is introduced. It is based on rotational block set, which is formed by a number of triangular wedges, and the construction of admissible velocity fields can be simplified to a combination of several rotational block sets. An application to the upper bound analysis of deep strip anchor in undrained clay is given to illustrate the utility and effectiveness of the proposed method, and include detailed comparisons with the results obtained by means of other approaches. It is shown that the value of pull-out capacity factor (11.42) for deep strip anchor is independent of the incline angle of anchor.