DRAIN PIPE FOR LIQUEFACTION COUNTERMEASURE

PROBLEM TO BE SOLVED: To ensure excellent workability, and to reduce the change with time of a liquefaction preventive effect by forming a linear slit with a specified pattern to a surface. SOLUTION: The drain pipe 10 for the liquefaction countermeasure is made of a pipe made of bored steel, linear slits S penetrated to the inside and the outside of the pipe are formed properly to a surface by a specified pattern P, and the groundwater of a peripheral ground can be made to flow in appropriately. A long-sized slit, in which the aspect ratio of a slit shape formed to the surface of the pipe 10 exceeds 1, is used as the linear slit S, and the width of the slit S is set in the grain size or less of soil and sand constituting the peripheral ground. The length of the pipe S is determined adequately in consideration of the inflow velocity and efficiency of groundwater and the strength or the like of the pipe. The front end section 11 of the pipe is formed in a shape corresponding to the conditions of the ground as an object, and closed. Accordingly, a liquefaction preventive effect can be maintained with maintenance hardly required approximately because the pipe can be executed efficiently and permeability after the execution of works is not also lowered.