Method for arranging protection layer on hole wall of large-diameter rotary-excavating hole

The invention relates to a rotary-excavating hole filling pile construction method, in particular to a method for arranging a protection layer on the hole wall of a large-diameter rotary-excavating hole. The method for arranging the protection layer on the hole wall of the large-diameter rotary-excavating hole comprises the steps that a core formwork is placed in the large-diameter rotary-excavating hole, concrete is poured in a gap between the rotary-excavating hole and the core formwork, the core formwork is upwards pulled by a certain height after initial setting of the concrete, pouring and pulling-up operation is circulated till the core formwork is completely pulled out, and thus the concrete forms the protection layer on the hole wall of the large-diameter rotary-excavating hole. Inthe hole pile foundation construction process, collapse possibly often occurs to the rotary-excavating hole to influence the subsequent construction progress, the protection layer is arranged on thehole wall of the rotary-ex