A weldless grating comprising: (a) a plurality of longitudinally extending primary load bearing members having an upper portion, a lower portion and a web located between said upper portion and said lower portion, the primary load bearing member having a plurality of spaced-apart openings in said web, the openings in each of said primary load bearing members being aligned with the openings in adjacent primary load bearing members; (b) a plurality of secondary load bearing members having an upper edge and a lower edge, the secondary load bearing members provided with first slots extending downwardly through the upper edge to provide top slots and with upwardly extending slots through the lower edge to provide bottom slots located substantially opposite said top slots, the secondary load bearing members positioned in the aligned openings in said web of the primary load bearing members, said top and bottom slots in said secondary load bearing member forming a locking engagement with said web surrounding said openings in said primary load bearing members, the secondary load bearing members provided with secondary downwardly extending slots through said upper edge, secondary downwardly extending slots located between primary load bearing members; (c) a plurality of tertiary load bearing members positioned in the secondary slots in the secondary load bearing members; and (d) a rod extending through said tertiary load bearing members and said primary load bearing members locking said tertiary load bearing members in the slots in said secondary load bearing members and locking said secondary load bearing members in the openings in said primary load bearing members to form said weldless grating.

A method and apparatus for building bridges from one location to another, and in which the construction activity takes place primarily at such terminal locations. Forms are assembled at one of the locations, such forms establishing the characteristics of the bridge deck to be built. When the forms are completed, they are elevated and suspended upon cables passing between the two locations. The forms are then pulled from one location toward the other, sequentially engaging with previously built and positioned forms until an entire complement of such forms extends between the two locations. The forms are then filled with concrete and finished. The forms provide an exterior finished surface for the bridge structure.

An automated weldless inter-locking grating assembly for bridge decks and the like which includes a plurality of primary load-bearing members located laterally, a plurality of transverse secondary load-bearing members and a plurality of trimorphic load-bearing members. Secondary load-bearing structural members are inserted sideways into apertures of primary load-bearing members and trimorphic load-bearing members. Thus, when a horizontal force is applied to alternate primary or trimorphic load-bearing members or any combination thereof, rotation of secondary load-bearing member or members occur to efficiently and automatically lock secondary load-bearing member or members into primary and trimorphic load-bearing member or members completing assemblage thereof into a rigid structural form.

A weldless grating comprising: (a) a plurality of longitudinally extending primary load-bearing members having an upper portion, a lower portion and a web located between the upper portion and the lower portion, the primary load-bearing member having a plurality of spaced-apart openings in the web, the openings in each of the primary load-bearing members being aligned with the openings in adjacent primary load-bearing members; (b) a plurality of secondary load-bearing members having an upper edge and a lower edge, the secondary load-bearing members provided with first slots extending downwardly through the upper edge to provide top slots and with upwardly extending slots through the lower edge to provide bottom slots located substantially opposite the top slots, the secondary load-bearing members positioned in the aligned openings in the web of the primary load-bearing members, the top and bottom slots in the secondary load-bearing member forming a locking engagement with the web surrounding the openings in the primary load-bearing members, the secondary load-bearing members provided with secondary downwardly extending slots through the upper edge, secondary downwardly extending slots located between primary load-bearing members; (c) a plurality of tertiary load-bearing members positioned in the secondary slots in the secondary load-bearing members; and (d) a rod extending through the tertiary load-bearing members and the primary load-bearing members.

A weldless grating comprising primary, secondary tertiary members wherein top and bottom slots in the secondary load bearing member form a locking engagement with the web surrounding openings in the primary load bearing members, the secondary load bearing members having secondary downwardly extending slots through the upper edge, the slots having an upper portion extending downwardly from the upper edge and a lower portion located below the upper portion, the upper portion having a first extent and the lower portion having a second extent, the first extent being greater than the second extent.