When a large-diameter shield tunnel is excavated close to an isolation wall, the lateral rigid boundary formed by the wall changes the propagation paths of ground loss, tail gap, and synchronous grouting disturbances. As a result, the ground responses on the tunnelling side and the wall-back side no longer satisfy the symmetric free-field assumption. This effect is more pronounced in soil-rock composite and karst strata, where wall constraint couples with stratigraphic heterogeneity and may cause settlement-trough offset and local deformation amplification. To clarify these differences, field monitoring was carried out in a practical project where the tunnel clearance from the isolation wall is approximately 0.1 times the tunnel diameter. Four typical sections, including soil-rock composite strata, a stiffness-transition zone, intact hard rock, and a karst-developed zone, were selected. The results show that the settlement on the tunnelling side is significantly larger than that on the wall-back side, and the settlement trough shifts away from the isolation wall. Horizontal displacement near tunnel depth mainly points toward the wall and decreases with increasing distance from the wall. Based on variations with wall distance and burial depth, a transverse spatial zoning pattern can be established, revealing shallow disturbance transmission, wall-body constraint, strong circumferential response, and attenuation on the far-wall side. The isolation efficiencies of the wall against settlement and horizontal displacement are 81.2%-94.1% and 43.1%-89.7%, respectively. Karst development weakens the continuous displacement transfer path, amplifying local ground deformation without a synchronous increase in wall response. The findings provide a basis for ground-response assessment and risk control during large-diameter shield tunnelling close to isolation walls. [Keywords] large-diameter shield tunnel; isolation-wall constraint; ground deformation; disturbance transmission; isolation effect