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The in-situ stress can significant influence the damage caused to rock. A comprehensive analysis of the in-situ stress field is essential for tunnel design, construction and geological monitoring. This study establishes a 3D geologic model using the finite difference method, explicit considering material heterogeneity through random field theory. After conducting 300 simulations, the distribution pattern of the in-situ stress field was statistically analyzed. The inversion accuracy, considering material heterogeneity, is superior to that for homogeneous materials at the measurement points, with smaller relative errors. The extent of in-situ stresses in both the horizontal and vertical directions of the model depend not only the burial depth but also on the physico-mechanical properties of the material. In particular, the distribution of the in-situ stress field exhibits heterogeneity in localized regions, influenced by the material's variability. In the river valley area, the river valley bank slopes are divided into three zones based on the stress force values: the stress release zone, the stress concentration zone, and the virgin rock stress zone. The stress distribution around the tunnel shows significant non-uniformity and irregular fluctuations, with alternating high-stress and low-stress regions. Notably, stress concentration occurs at the crown, sidewalls, and both sides of the tunnel bottom. These in-situ stress fields, which account for the spatial variability of rock parameters, provide a more realistic and accurate reference for engineering practice.

来源平台：GEOTECHNICAL AND GEOLOGICAL ENGINEERING