Folded sheets of material for use as a structural member and assembly thereof

A sheet of material defining at least one tab and pair of slots, and first, second, third, fourth, fifth, sixth, seventh, eighth, and ninth substantially straight fold lines each extending from a first end of the sheet to a second end of the sheet, the at least one tab and pair of slots are spaced from each other in a direction substantially perpendicular to the fold lines,

• wherein the first fold line forms a first portion between a third end of the sheet and the first fold line, a space between the third end and the first fold line being a first distance,
• wherein the second fold line forms a second portion between the first fold line and the second fold line, a space between the first fold line and the second fold line being a second distance,
• wherein the third fold line forms a third portion between the second fold line and the third fold line, a space between the second fold line and the third fold line being a third distance,
• wherein the fourth fold line forms a fourth portion between the third fold line and the fourth fold line, a space between the fourth fold line and the third fold line being a fourth distance,
• wherein the fifth fold line forms a fifth portion between the fourth fold line and the fifth fold line, a space between the fourth fold line and the fifth fold line being a fifth distance,
• wherein the sixth fold line forms a sixth portion between the fifth fold line and the sixth fold line, a space between the fifth fold line and the sixth fold line being a sixth distance,
• wherein the seventh fold line forms a seventh portion between the sixth fold line and the seventh fold line, a space between the sixth fold line and the seventh fold line being a seventh distance,
• wherein the eighth fold line forms a eighth portion between the seventh fold line and the eighth fold line, a space between the seventh fold line and the eighth fold line being a eighth distance,
• wherein the ninth fold line forms a ninth portion between the eighth fold line and the ninth fold line, and forms a tenth portion between the ninth fold line and a fourth end of the sheet that is opposed to the third end of the sheet, a space between the eighth fold line and the ninth fold line being a ninth distance, a space between the ninth fold line and the fourth end being a ninth distance,
• wherein the fold lines are spaced such that folding the sheet along the hold lines forms an elongated structural member having an interior space, and places at least one pair of slots in substantial alignment for receiving the at least one tab such that a substantially X shape is formed by the first, third, and sixth portions in the interior space when view from one of the first end and the second end, wherein the X shape extends between the first end and the second end.