Abstract: The prestressed double-layer lining structure of a shield water conveyance tunnel is a novel type of support structure with great potential for high-internal-pressure water conveyance projects, and its stress characteristics are a key focus in structural design and research.To investigate the mechanical adaptability of this lining at different burial depths, a 1 ∶5 scale model test was conducted based on the Pearl River Delta Water Resources Allocation Project.The results showed that: the prestressed lining is the primary load-bearing component of the prestressed double-layer lining, with higher internal force levels than those on the segmental lining.Under the combined action of internal and external loads, the overall deformation of the structure exhibits a "horizontal duck-egg" shape.As burial depth decreases, the risk of concrete cracking in the prestressed double-layer lining increases, and the contact pressure between the lining layers decreases, the interactive load-sharing capability between the segmental lining and the prestressed lining weakens, resulting in more microstructural damage cracks.Therefore, in the structural design of pressure water conveyance tunnels with prestressed double-layer linings, greater attention should be paid to their mechanical behavior under shallow burial conditions.This study can serve as a reference for the design of shield water conveyance tunnels with prestressed double-layer linings.