Abstract: A method for constructing an underpass below a first section of a pre-existing first way where a first quantity of debris must be removed from an underpass space below the first section to form the underpass and enable passage of traffic along a second way. The method comprising the steps of providing foundation pairs on either side of the underpass space, each pair including first and second foundations on opposite sides of the first section, halting traffic along the first section, removing the first section, and removing at least a portion of the first quantity of debris from within the underpass space sufficient to enable installation of a superstructure substantially between the first and second foundation pairs and supported by the top ends of the first and second foundation pairs.

Abstract: A method for constructing an underpass below a first section of a pre-existing first way where a first quantity of debris must be removed from an underpass space below the first section to form the underpass and enable passage of traffic along a second way, the method comprising the steps of providing foundation pairs on either side of the underpass space, each pair including first and second foundations on opposite sides of the first section, halting traffic along the first section, removing the first section, removing at least a portion of the first quantity of debris from within the underpass space sufficient to enable installation of a superstructure substantially between the first and second foundation pairs and supported by the top ends of the first and second foundation pairs, providing a superstructure substantially between the first and second foundation pairs and supported by the top ends of the first and second foundation pairs, constructing a new first section and resuming first way traffic.

Abstract: An apparatus for opening a mechanical bridge. The apparatus includes at least two adjacent bridge spans where the first of the bridge spans is removable from its initial position and the second of the bridge spans is at least partially movable into the space originally occupied by the first span so that at least a portion of the second bridge span can be separated from yet a third adjacent span. This forms an opening between the second and third spans. Alternatively, a span can be moved laterally and then longitudinally to open a section of the bridge.

Abstract: A method and apparatus for opening a mechanical bridge, the apparatus including at least two adjacent bridge spans where the first of the bridge spans is removable from its initial position and the second of the bridge spans is at least partially movable into the space originally occupied by the first span so that at least a portion of the second bridge span can be separated from yet a third adjacent span thereby forming an opening between the second and third spans and another method whereby a span is first moved laterally and then longitudinally to open a section of the bridge.

Abstract: A mobile crane including a wheeled carriage, support members having distal ends, mounted to the carriage and extendable laterally therefrom in two positions including a retracted position with the distal ends adjacent the carriage and an extended position with the distal ends separated from the carriage, first and second glide beams coupled to the distal ends for movement along a movement axis perpendicular thereto, at least one support beam connected to the tops of the glide beams and a hoist trolley coupled to the support beam. The components operate together to provide a fully supported gantry crane having a variable width useful in lifting and transporting various items including items which are wider than the carriage.

Abstract: A mobile crane including a wheeled carriage, support members having distal ends, mounted to the carriage and extendable laterally therefrom in two positions including a retracted position with the distal ends adjacent the carriage and an extended position with the distal ends separated from the carriage, first and second glide beams coupled to the distal ends for movement along a movement axis perpendicular thereto, at least one support beam connected to the tops of the glide beams and a hoist trolley coupled to the support beam. The components operate together to provide a fully supported gantry crane having a variable width useful in lifting and transporting various items including items which are wider than the carriage.