Excessive sinking preventing method for construction of open caisson of tapered-bottom and spiral flow type pool

The invention provides an excessive sinking preventing method for construction of an open caisson of a tapered-bottom and spiral flow type pool. The method comprises the following steps: arranging locking feet between blade feet at the lower part of the open caisson and the tapered bottom; dividing the pool wall into an upper part and a lower part and respectively constructing; arranging a supporting plate on the outer side of the upper end of the upper wall; arranging a supporting beam at the outer side of the lower end of the upper wall; calculating the specification and size of the locking feet, the supporting beam and the supporting plate, the reinforcing bars and the concrete intensity; constructing the lower wall by the open caisson method; then constructing the locking feet; constructing the supporting beam and the upper wall at the same time; backfilling sand-included stone at the outside of the wall; constructing the supporting plate; excavating the soil from the tapered bottom; constructing the reinforced concrete of the tapered bottom; then constructing a flow stabilizing plate, an inner barrel and a platform. According to the excessive sinking preventing method for the construction of the open caisson of the tapered-bottom and spiral flow type pool, the technology of locking and then dragging is adopted, so that the construction is convenient, the operation is easy, the construction is safe, the time is saved, and the technical problems of excessive sinking, inclining, sudden sinking to cause injury in the construction of the tapered-bottom and spiral flow type pool under the open caisson method can be effectively solved.