Construction method of micro pile for skin friction column composed soil cement

摘要

The present invention provides a method for constructing a micropile to form a skin friction column made of soil cement, which is provided to improve foundation bearing capacity and horizontal load-resisting capacity by forming the skin friction column around the micropile. According to a proper embodiment of the present invention, the method for constructing a micropile comprises step (a) of excavating an excavation groove on the ground to have a bigger cross-sectional area than that of the micropile and the predetermined depth; step (b) of filling a grout material in the excavation groove; step (c) of forming a soil cement column which shows a mixture of the grout material and stratal soil from the circumference of the micropile with one or more stirring impellers by making the micropile penetrate through the excavation groove by rotation until the micropile reaches a support layer after inserting the micropile into the excavation groove; and step (d) of forming a core column by filling the grout material in the micropile having completed penetration. In step (c), the micropile penetrates through the excavation groove to stand with a predetermined distance from the ground. The method also includes a step of curing cast-in-place concrete after filling the cast-in-place concrete in the excavation groove which becomes empty due to penetration of the micropile after step (d).