The invention relates to a foundation pit support
pile using a steel
pipe pile to replace a cast-in-place
pile rock-socketed, and belongs to the field of
foundation engineering. The foundation pit support pile comprises an upper support cast-in-place pile and a lower rock-socketed steel
pipe pile, wherein the rock-socketed steel
pipe pile consists of a plurality of steel pipes embedded into a
bedrock and
cement paste poured; and the upper parts of the steel pipes extend into the support cast-in-place pile to be lapped with a pile body reinforcing bar. During construction, a hole is formed in acomplete
bedrock surface, after the hole is formed, the hole is drilled by a drilling
machine, the steel pipes are placed into the hole, and the
cement paste is poured into the hole, so that the steel pipes and the
bedrock are fixedly connected into a whole, and the rock-socketed replacement of the support cast-in-place pile is realized. The method has the advantages that the hole
diameter of thesteel pipe pile is larger, the number of holes is small, the centering is easy during pipe placement, the cost is low, the construction speed is high, and the process is simple. A
karst cave can be vertically spanned in a
karst area, so that materials are saved, and the stability of a rock-socketed section of the support pile is ensured. Meanwhile, in a bedrock fracture development area, the strength of the bedrock is greatly improved by pouring the
cement paste, and the problem of strength of the bedrock due to fracture development is solved.