a material and method is provided for lining man - entry sized pipes and securing the lining to the pipe . a plurality of lining panels are positioned along the interior surface of a pipe so as to form a plurality of adjacent wall portions extending through the pipe . the lining panels are each formed with a plurality of t - shaped flanges extending perpendicular to and along said outer wall of the lining panel . a stiffening panel is positioned between at least selected pairs of the t - shaped flanges . the hollow interiors of the stiffening panels are formed to receive and hold grout . the grout when cured provides strength and support for a second layer of grout injected into an annulus between the pipe &# 39 ; s inner surface and an outer surface of the lining .