<p>During open-pit mining, the geotechnical strength and geological structure of the slope are rather complicated. Varying geological structures and rock mass strengths can lead to diverse failure modes of slopes. Particularly, fault-containing geological structures can exert a pivotal influence on the slope stability and ultimately affect the safe production of open-pit mines. This paper focuses on the K5-K6-K7 convex slope formed from the top to the bottom in the eastern mining area of Kangcheng Stone Mine. Through similarity simulation, the failure modes and deformation characteristics of the convex slope under two conditions, namely with and without a fault tectonic alteration zone, were analyzed. Furthermore, the results of similarity simulation experiments were verified with the aid of FLAC^3D based on the strength reduction method. The key findings are as follows: (1) The failure mode of the K5-K6-K7 slope and similar convex slopes in Kangcheng Stone Mine is overall arc-shaped sliding. The horizontal displacement of the convex slope surface mainly occurs on both sides of the convex surface. (2) The displacement process of the slope can be divided into three stages. In Stage I, i.e., the stable deformation stage, the displacement is relatively mild, accompanied by the emergence of small cracks. In Stage II, i.e., the local failure stage, the displacement changes increasingly noticeably, and small cracks keep expanding into large ones in the upper left, upper middle, and lower middle parts of the slope. Besides, these cracks penetrate the inner part of the slope, ultimately inducing plastic failure and slope sliding. In Stage III, i.e., the failure stage, the deformation and displacement continue at an accelerated rate. Moreover, cracks extend from the upper part to the bottom of the slope and penetrate the inner part of the slope, resulting in damage and sliding. At this time, the displacement distance reaches the maximum. (3) Due to its low strength, the rock mass in the FTA zone exerts a relatively strong influence on the intact surrounding rock mass. During slope failure, the displacement is mainly concentrated on the midline of the convex slope ridge and in the upper part on both sides are relatively large. The stability of the slope with a FTA zone is 0.067 less than that of the slope without a FTA zone, as calculated by the strength reduction method.</p>