New Jersey Department of Transportation Movable Bridge Inspections

NJDOT Movable Bridge Inspections

Type:  Various Types of Movable Bridges
Location: Various
Owner: New Jersey Department of Transportation


Stafford Bandlow Engineering personnel have performed the mechanical and electrical inspections of 19 movable bridges including seven bascule, five swing, six vertical lift, and one Strauss heel trunnion bascule bridge. Drive types include both electro-mechanical and electro-hydraulic drive machinery.  The majority of bridges have been inspected over multiple inspection cycles with inspections ranging in depth from Type III (cursory) to Type I (in-depth). Some of the bridges are new within the past three years while others date to the early 1900’s.

Electrical services provided as part of these inspections have included functionality testing, verification of adequacy of safety interlocks, insulation resistance testing “megger”, voltage profile and voltage regulation testing, load current measurement and recording of all electrical drives, analysis and preparation of comprehensive reports.

Mechanical services provided as part of these inspections have included gear tooth measurements, bearing clearance measurements, coupling alignment verification, evaluation of mechanical integrity, functional testing, strain gage balance testing and drive analysis, and preparation of comprehensive reports.

The work performed also included a special project to design emergency operating machinery for an existing bridge that was no longer operational utilizing the original electro-mechanical drive machinery.