In order to study the contribution of segmental protection-wall to the horizontal bearing capacity of anti-slide piles,based on an artificial drilled anti-slide pile engineering,the model structure of segmental protection-wall and integral pile was designed by using similarity theory. With two same actuators of MTS respectively loading horizontally on the top of pile with protection-wall and of pile with no protection-wall, a model test with the scale of 1∶10 was carried out to study the interaction of segmental protection-wall and integral pile structure of anti-slide pile under horizontal load. By simultaneously loading horizontally of MTS actuators,the following results were achieved. Firstly, with the same horizontal displacement of pile top,the soil pressure at the bottom of pile with segmental protection-wall is larger than that of pile with no protection-wall,but the passive soil resistance on the top of pile is reverse,and reinforcing of upper passive soil of flexible pile could improve the horizontal bearing capacity.Secondly,with the same horizontal displacement of pile top,the maximum strain of tensile steel bar of pile structure with segmental protection-wall is always larger than that of pile with no protection-wall.With the increase of horizontal displacement of pile top,the section position of maximum strain of tensile steel bar of pile is moving down,but the moving velocity of section position of pile with protection-wall loges behind that of pile with no protection-wall.Furthermore,with the increase of horizontal load,the proportion of maximum strain of tensile steel bar with protection-wall than that of with no protection-wall increass first and then decreases,and the maximum proportion is 165.03% with the horizontal displacement of 30 mm and the minimum proportion is 20.23% with the horizontal displacement of 90 mm.Thirdly, with the horizontal displacement of pile top as the control standard of horizontal bearing capacity of pile,the horizontal bearing capacity of test pile in this paper increases more than 20%, and in the pile engineering practice,the contribution of horizontal bearing capacity improvement of segmental protection-wall can be computed by the formulas and reduction factor in the present work.
