Trench-box panel

Claim 2

A trench-box panel comprising an array of horizontal members, arranged one on top of another and welded together in mutually adjoining pairs, at least one element of one member of each said pair of mutually adjoining members co-operating with at least one adjoining element of the other member of the pair to define a horizontally-extending cavity which is closed by said elements except at the ends of the cavity, adjacent ends of mutually adjoining members being in mutually staggered relationship to leave spaces between the ends of alternate horizontal members at each of two vertical edges of the panel, and vertical panel-strengthening members welded to said ends of the horizontal members, at both said vertical edges of the panel, by means of welds, so as to seal the ends of said horizontally-extending cavities, some of said welds being welds in said spaces between the horizontal members on the one hand and at least one said vertical member at each said vertical edge of the panel on the other hand.

Claim 3

A panel as claimed in claim 1 wherein the horizontal members are of a uniform length and are longitudinally staggered to provide said spaces between the ends.

Claim 4

A panel as claimed in claim 1, wherein the vertical members at each said vertical edge of the panel comprise a vertical, two-element, angle member and a vertical flat member which extends from one edge of one said element of the angle member and which faces the other said element of the angle member.

Claim 5

A panel as claimed in claim 3 wherein said vertical angle member is said one member welded in said spaces to said horizontal members.

Claim 6

A panel as claimed in claim 1, each said horizontal member comprising a horizontal element, a pair of mutually facing vertical elements extending from inside and outside edges of the horizontal element, and a pair of flange elements extending inwardly towards each other from distal edges of the vertical elements, mutually adjacent flange elements and horizontal elements of mutually adjacent members being welded together, and a horizontal closed-section or box-section member welded to the flange elements of a top or bottom one of the first-mentioned horizontal members.

Claim 7

A panel as claimed in claim 1 wherein the horizontal members are of a uniform length and are longitudinally staggered to provide said spaces between the ends; wherein the vertical members at each said vertical edge of the panel comprise a vertical, two-element, angle member and a vertical flat member which extends from one edge of one said element of the angle member and which faces the other said element of the angle member; wherein said vertical angle member is said one member welded in said spaces to said horizontal members; and each said horizontal member comprising a horizontal element, a pair of mutually facing vertical elements extending from inside and outside edges of the horizontal element, and a pair of flange elements extending inwardly towards each other from distal edges of the vertical elements, mutually adjacent flange elements and horizontal elements of mutually adjacent members being welded together, and a horizontal closed-section or box-section member welded to the flange elements of a top or bottom one of the first-mentioned horizontal members.