Abstract: A coupling trolley is provided for a rail or runway beam that is longitudinally translatable relative to a member located above and extending transversely of the rail or runway beam. The trolley has rollers to engage and support the rail or runway beam via upper flanging thereof, and has first and second supporting engagers for the member, specifically lower flanging thereof. The trolley is movable with the rail or runway beam and relative thereto. When the trolley is stopped by its first engager reaching said member as the rail or runway beam is advanced with the trolley, the second engager of the trolley is movable by the end of the rail or runway beam, from non-engagement towards and into securing engagement with the member where it is held by cooperation with the upper surface of the rail or runway beam.

Abstract: The invention provides a method for furbishing or renovating large span overhead structures, for example the roofs of railway stations, or bridges and the like, and utilizes apparatus which comprises a plurality of runway beams suspended in spaced parallel disposition from the main ribs or framework of an overhead structure said beams spanning a plurality of said ribs or framework and being longitudinally displaceable relative thereto, and a work platform or platforms suspended from said runway beams and being displaceable therealong. Thus arranged, the overhead structure can be treated for substantially its entire length by alternately advancing the work platforms along the runway beams and the runway beams relative to the structure.