| I.P Abstract & Summary |
The present invention relates to an extendable perforated pipe having an improved structure so as to prevent clogging of through-holes with external soil, wherein the extendable perforated pipe can be formed in a spiral pipe shape by spirally winding a material and can be extended in the longitudinal direction by sliding a cover part on the upper side of a perforated part in which a plurality of the through-holes are perforated. In the extendable perforated pipe, drainage properties in an extension operation can be improved by increasing the width interval of the perforated part, first and second bent portions can be bent in directions opposite to each other at the lateral edge portions of the cover part and the perforated part so as to adjust the longitudinal extension interval, and by a cover member of a braided structure being arranged outside the perforated pipe, a separate nonwoven fabric can be omitted during construction work of the perforated pipe. |
