The stability of the soils between unbaffled cantilever anti-slide piles should be considered during design. Based on model test results, a three-dimensional sliding surface model for the soils between cantilever anti-slide piles is established. The upper bound limit analysis method is used to obtain the maximum height of free face of the soils. The strength reduction method is combined with the upper bound limit analysis method to calculate the stability coefficient of the soils between piles. Both methods...