As a common waterproof material used in tunnel construction

nonwoven fabrics are widely used as a cushion in the waterproof layer. But the water pressure and structure stress distribution mechanism after using it hasn’t been studied thoroughly. Through the research of Xiang’an subsea tunnel

the effect of nonwoven fabrics has been studied with different proof-drainage patterns; i.e. whole block

block combined with drainage and drainage modes. The primary research method adopted is simulated model test with proportional scale of 1:38.88. Its test apparatus can apply both soil pressure and water pressure at the same time. According to the model test

the conclusion is as follow: under whether whole block or limited drainage condition

nonwoven fabrics have a good function of water collection and absorption; the nonwoven fabrics can strengthen the water fluxility and complementarity around the lining to make the water pressure distribution on it more well and also improve the stress condition around the lining structure.