To explore the effect of soil mechanical parameters and their spatial distribution characteristics on the construction deformation behavior of deep excavation construction, a three-dimensional construction mechanics model of a dual-phase soil-rock stratum deep excavation was established using ABAQUS finite element software. Various construction scenarios were analyzed to compare and study the induced deformation patterns in the dual-phase soil-rock stratum. The study considered factors such as soil stratum mechanical parameters and the inclination angle of the soil-rock interface. The research findings indicate the following: (1) As the elastic modulus of the soil increases, the lateral displacement of the pile decreases. The lateral displacement curve changes from a monotonically decreasing distribution to a "fish belly" distribution with an initial increase followed by a decrease. The maximum lateral displacement point also moves downward from the pile top. (2) As the cohesive strength of the soil increases, the lateral displacement of both the soil and the pile decreases. Within a certain safe range, the cohesive strength has a relatively small influence on soil displacement. (3) The inclination angle of the soil-rock interface significantly affects the deformation of the support structure. It can alter the lateral soil pressure exerted on the pile. When the soil-rock interface is inclined towards one side of the anti-sliding pile, it increases the lateral soil pressure, resulting in greater pile and soil displacement. The impact of the soil-rock interface on the pile within the rock layer or its vicinity is relatively small.