Abstract: Based on geological characteristics of the three-level terraces in the Yangtze River at Wuhan, we analyze the feasibility of depressurization by blind trench drainage. We introduce the practical application of drainage depressurization in engineering projects, present the theoretical analysis and experimental results of blind trench drainage test models, and evaluates the reliability and durability of blind trenches. The findings demonstrate a close agreement between the calculated seepage flow of the test models and the actual experimental results. When the foundation of underground structures is situated in less permeable clay layers,the blind trench drainage technique proves effective in reducing the buoyant water level of these structures. Additionally, blind trenches exhibit minimal seepage flow, resulting in negligible long-term impact on the surrounding environment. Consequently, in areas where the foundations of underground structures lie within the clay layers of the three-level terraces in the Yangtze River at Wuhan, the blind trench drainage technique proves highly efficient in significantly reducing or even completely eliminating the buoyant water level of underground structures. This approach holds substantial potential for application, particularly in the anti-floating of underground stations of subway systems with relatively low self-weight.

Key words: anti-floating stability design, blind trench, depressurization by drainage, feasibility analysis, three-level terrace