Abstract: A method of constructing a modular bridge across a span comprises at least a first trestle on the home bank of the span, placing a first module of a modular launching rail on the trestle, connecting one or more subsequent launching rail modules to the launching rail being formed, placing a first bridge module on the launching rail, connecting one or more subsequent bridge modules to the bridge being formed, booming out the launching rail across the span and launching the bridge across the span along the launching rail. A trestle for use in such a method is also disclosed.

Abstract: A method of deploying a modular bridge across a span having a home bank and a far bank wherein a plurality of modular bridge sections are utilized includes providing a launching vehicle with a support for bridge launching. The method employs the steps of booming out a launching rail from the vehicle until the launching rail reaches the far bank and thereafter placing the modular bridge sections on the launching rail in order to form the bridge.

Abstract: Laser welding apparatus includes a first mirror whose angle may be adjusted but which is fixed in position and on which a laser beam is incident. The first mirror reflects the laser beam onto a second mirror which may be rotated through at least 180.degree. about the axis of the articles to be welded and which reflects the laser beam onto a third mirror whose angle may be adjusted and which may be rotated through at least 360.degree. about the axis of the articles to be welded. The laser beam then passes to a focussing mirror which focusses the beam through a welding nozzle onto the surfaces to be welded. In use, the third mirror is continuously rotated about the entire periphery of the articles to be welded and the positions and/or angles of all the mirrors are adjusted to ensure that the laser beam is transmitted along the desired pathway.

Abstract: A bridge module comprises two longitudinal main girder structures and a central deck having a deck surface, said main girder structures being foldably connected are along each side of said central deck and being foldable between an operative position in which said main girder structures offer extensions of said deck surface on either side of said central deck for use and a closed position in which said main girder structures are folded beneath said deck.

Abstract: A stackable freight container comprising a rigid bottomless container body 10 and a separate freight-carrier pallet 11 which can be bolted into the open underside of the body 10 by means of shoot-bolts 37 to close the container and form its load-carrying floor. When the closed container is placed on a flat supporting surface 40 the lower edges of the body 10 rest on the surface 40 with the loaded pallet 11 supported clear of the surface 40 by the shoot-bolts 37, the weight of the loaded pallet 11 then preventing the withdrawal of the shoot-bolts. To open the container it must be lowered on to packing 39 to take the weight of the loaded pallet 11 off the shoot-bolts 37 so that they can be withdrawn.The body 10 can be used inverted as a floating pontoon unit, whose deck is afforded by the pallet 11.