The excess pore water pressure

which imposes a negative role on the stability of excavation face

generated in sand due to the train vibration load of a running metro when a slurry shield cross under the metro. This paper presents an investigation on the effect of the train vibration load on the generation of excess pore water pressure in three categories of sand specimens through dynamic triaxial tests. It is concluded that the excess pore water pressure increases with the rise of amplitude of train vibration load; but the increase of excess pore water pressure is not significant when the amplitude of train vibration load is less than 10 kPa; and the influence of train vibration load on the excess pore water pressure is more significant when the excavation face pressure declined; moreover

the decrease of vertical pressure plays a bigger role in the growth of excess pore water pressure than that of horizontal pressure. The vibration load has the most significant influence on the excess pore water pressure in saturated loose fine sand. The excess pore water pressure could reduce the resultant pressure on filter cake at least 33%.