circumferential

M.Tokiyoshi1), H.Kudo1), M.Endo1), K.Inoue1)N.Shibasaki2), T.Nakayama2), H.Matsukuma2), M.Kodera2)Y.Niinomi3), M.Masuko3) P.Vanspeybroeck4) 1)High stiffness Polyethylene Pipes Association, JAPAN 2)Tokyo Electric Power Company.,Inc , JAPAN 3)Tokyo Electric Power Service Company.,Ltd, JAPAN 4)BECETEL v.z.w , BELGIUM Abstract Polyethylene pipes are successful worldwide due to the superior performance (Flexibility, light weight, lifetime, tighten joint) for water and sewerage supply. However according