In Vietnam, the solution of designing and
constructing deep foundation pits with the geology of sandy or
clayey sand is very difficult, especially in case soil mix mud. In
some deep foundation pits, the unreasonable treatment solution
causes the bottom plug of the foundation pit to be pushed up to the
foundation pit or not to pump a foundation pit dried. Solving
those problems, this article introduces a particular case study,
sealing the bottom of the foundation pit for no
14 of Yen Xa
drainage works with the Jet grouted bottom plug hydraulic
barriers. To treat the soft soil layer, mix organic without breaking
the upper soil layers, this solution uses Jet-grouting technology
with a mixture of materials including cement, fly ash, blast
furnace slag, lime in a reasonable proportion to ensure
waterproof and not uplift the massive bottom plug hydraulic
barriers when excavating soil in the pit. Results of calculation and
acceptance after the foundation pit is completed show that this is a
good solution, high reliability and can be applied to seal the
bottom of the foundation pit in similar geological conditions.