Glossary

ASHTO- The American Association of State Highway and Transportation Officials is comprised of transportation officials from states and agencies. The AASHTO sub committee developed the Guide Specifications for Design of Pedestrian Bridges. This guide serves a manual for pedestrian bridge design requirements.

ABUTMENTS – A structure that supports the ends of a bridge. Abutment design usually depends on the weight rating of the bridge and the geotechnical reports.

AISC – Refers to the American Institute of Steel Construction. The AISC design code is used for design and fabrication of the steel components of the bridge.

ANCHOR BOLTS – Bolts which are used to attach the bridge to the abutments. The precise layout pattern of the bolts are indicated in the bridge plans.

A-588 STEEL – Otherwise known as self weathering steel, cor ten , or rust resistant steel.

BEARING ASSEMBLY – Is the steel plate which is used to attach the bridge to the abutments, with the use of the anchor bolts.

BOTTOM CHORD – A structural truss part of the bridge which runs longitudinal.

CAMBER – Is a slight upward curve which is engineered into the design of the bridge. The dead load camber off sets the weight of the bridge itself.

DEFLECTION – The engineered amount of movement the bridge will sustain when it is bearing a load.

DIAGONAL – The angled member of the bridge truss which joins the upper and bottom chords of the bridge.

ELEVATION DIFFERENCE – The difference in the vertical height of the abutments.

ELEVATION VIEW – A side view drawing of the bridge.

GALVANIZE – Is generic term for protective zinc coating on steel.

HALF THROUGH SYSTEM – A type of bridge that does not have any overhead lateral bracing system.

LIVE LOAD – Is the total weight borne by the bridge. The weight the bridge is rated for is indicated by the pound per square foot, example 85 psf or 10,000 single live load limit.

PENTACHORPHENAL – A chemical compound which is used as a wood preservative.

RUB RAILS – A wooden plank type of rail attached to the inside of the trusses, above the deck. 

SKEWED ENDS – When the abutments are unsymmetrical or not parallel to each other. This requires the design of the bridge to compensate for this situation.

TOP CHORD – The top structural longitudinal part of the bridge.

VERTICALS – A structural part of the bridge which connects the top and bottom chord.