This invention relates to the field of bridge construction technology and provides a method for constructing a steel
pipe pile cofferdam in a hard clay layer, comprising the following steps: S1, driving steel
pipe piles at the designed location to form a
cofferdam; S2, determining the ratio of
sodium silicate solution and
oxalic acid solution injected into the support layer and the Baumé degree of the
sodium silicate solution based on the pH value of the hard clay layer, the
compressive strength required for the underlying support layer during bridge
abutment construction, and the shortest time for the support layer to maintain this
compressive strength; wherein the support layer is the hard clay layer from below the
abutment to the bottom of the steel
pipe piles; S3, injecting
oxalic acid solution and
sodium silicate solution sequentially into the support layer at a predetermined location within the
cofferdam according to the stated ratio. This method utilizes the inherent high
bearing capacity of the hard clay layer, and by injecting
sodium silicate solution and
oxalic acid solution of predetermined concentration and ratio, its
compressive strength is improved, enabling it to possess sufficient
bearing capacity for a period of time to withstand the construction load of the
abutment.