Abstract: Double-shield tunnel boring machines (TBMs) are prone to jamming incidents when tunneling through jointed rock masses. To effectively mitigate such risks, it is therefore essential to investigate the mechanisms underlying TBM jamming in jointed geological conditions. In this study, a numerical model is established using the discrete-element software 3DEC. Combined with an orthogonal experimental design, the influences of geological conditions, joint characteristics, and anti-jamming measures on the contact pressure between the surrounding rock and TBM are comprehensively evaluated. The results indicate that the burial depth and over-excavation clearance exert extremely significant effects on the contact pressure. The angle between the joint strike and tunnel axis, as well as joint spacing, exhibit very significant influences. The soft filling length and lateral pressure coefficient have significant impacts, while other parameters show negligible effects.