Roll formed metal member with reinforcement indentations

A metal member (10), (70), (80), (120), (132), (150), (140), (152), (160), (172), (184), (200), (220) having at least one edge formation, web extending from said edge formation, a plurality of generally triangular formations (26), (92), (126), (148), (156), (168), (182), (190), (206), (222) formed in said web at spaced intervals, said triangular formations being alternately reversed relative to one another and defining a base and three corners, a plurality of generally diagonal struts (28), (106), (128) extending across said web between adjacent said triangular formations, edge portions (14, 16), (74,76), (84,86), (124) along either edge of said web, with said struts extending from one said edge portion to the other and merging integrally therewith, first flange formations (30,32), (94,96) formed from said web around said generally triangular formations along each side of said struts, and lying at an angle to said web, whereby to give said diagonal struts a generally channel shaped cross section, and, second flange formations (34), (98) formed along a further side of said triangular formations and forming intermittent flanges along said web edges, at said base of each said triangular formation, and comprising,

• corner flange formations (36, 38, 40) (100,102,104) extending around said corners of said triangular formations, said corner flange formations lying at an angle to said web which is less than said angle of said first flange formations;
• generally three-sided reinforcement indentations (42,44), (108, 110), (130) formed in said web and extending partially into each end of each said diagonal strut, each of said three-sided indentations (42,44), (108,110), (130) comprising a first base side (46,52) which is linear and generally parallel with a said edge of said web, a second linear angled side (48, 54) extending from said base linear side and parallel to and spaced from a linear edge portion (32) of one of said generally triangular formations (26), thereby defining a substantially linear strut root portion (58, 60) formed from said web and merging into said respective diagonal strut and a curved third side (50, 56) extending from said base linear side and meeting said second linear side at an apex, and wherein said apex extends into said diagonal strut portion (28) of said web, wherein said curved third side (50, 56) of said generally three-sided indentation is spaced from the adjacent said curved base corner (36, 38) of a said generally triangular formation, thereby defining a generally curved strut root portion (62, 64), and wherein said linear strut root portion (58, 60) is spaced from said curved strut root portion (62, 64), whereby each said diagonal strut (28) extends from both a generally curved strut root portion and a linear strut root portion formed from said web;
• and,
• an indented web portion of three-sided shape extending between each said first base side (46, 52), said second linear angled side (48, 54), and said curved third side (50, 56).