abutmentThe heavy block a bridge rests on at each bank. It carries the end of the span and holds back the earth of the bank. On an arch bridge the abutments also resist the sideways push of the arch.
arch bridgeA bridge held up by a curve that pushes on its ends. The arch passes the load outward and down to the abutments. The Romans built stone arch bridges such as the Alcántara Bridge in Spain, finished in 106 AD.
beam bridgeThe simplest bridge: a flat span resting on supports. A log laid across a stream is a beam bridge. The farther apart its supports, the weaker it gets, so one beam span is rarely longer than 250 feet (about 80 meters).
bridgeA structure that takes a path across an obstacle. A bridge can cross a river, a valley, a road or a railway. Most have a flat deck held up by beams, arches or cables.
cable-stayed bridgeA bridge whose cables go from deck to tower directly. The cables normally fan out from the tower or run side by side in parallel lines.
Show all 36 terms (31 more)
Bridges and their parts, continued
cantilever bridgeA bridge built of arms that are held at one end only. A cantilever sticks out into space like a diving board. Scotland's Forth Bridge, an early cantilever bridge, held the record for the longest span in the world for 29 years.
deckThe floor of a bridge, where the roadway runs. Decks are built of wood, steel, concrete or open metal grating, and many are topped with pavement or railroad track.
loadAny weight or force that presses on a bridge. Dead loads never go away: the bridge has to hold up its own weight. Live loads come and go, such as traffic. Wind and earthquakes are counted too.
pierA pillar standing under the middle of a bridge. A pier rests on a foundation and holds up the deck. A bridge with a single span has no piers.
spanThe reach of a bridge from one support to the next. The longest spans in the world belong to suspension and cable-stayed bridges, which hang the deck from high-strength steel cables.
suspension bridgeA bridge whose roadway is hung from long main cables. The main cables are anchored in the ground at each end. Simple versions with no vertical hangers have a long history in mountain regions.
truss bridgeA bridge carried by a web of bars set in triangles. The straight bars of the frame are pulled or squeezed as a load crosses. Builders usually make truss bridges from steel bars.
Forces and materials 12
bedrockThe hard rock layer that everything else sits on. A bridge rests on foundations that pass its weight down into the ground. Engineers study the soil and rock at a site before they design them.
brittleBreaking with a clean crack and hardly any stretch. Glass and cast iron are brittle. A brittle material often breaks with a sharp snapping sound.
compressionThe squeezing force that tries to shorten a part. The weight of a beam bridge pushes straight down on its piers, which are in compression. An arch works in compression too.
corrosionDamage that air and water slowly do to bare metal. Rust forms when iron corrodes. Painting is one way to protect the metal.
ductileAble to stretch a long way before it breaks. Gold and copper are ductile metals. In its pure form, no metal is more ductile than platinum.
equilibriumA balance in which no force wins, so nothing moves. A bridge at rest is in equilibrium: its supports push up exactly as hard as its loads push down.
forceAnything that pushes, pulls or twists an object. Tension and compression are the two forces found in every bridge.
gravityThe tug of the Earth that gives a load its weight. Gravity acts on the bridge itself and on everything that crosses it. The word comes from the Latin gravitas, weight.
safety factorHow many times stronger a thing is than it has to be. Bridges and buildings are made far stronger than everyday use demands, to allow for emergencies, unexpected loads, misuse and wear.
strengthThe most load a material can bear without failing. Engineers work out the highest load a bridge could meet, then how much material is needed to resist it.
structureA thing built to stand firm and carry weight. Buildings, bridges and machines are structures made by people. Nature has structures too, from minerals to living things.
tensionThe pulling force that tries to stretch a part. The cables of a suspension bridge are in tension. So is the rope in a tug of war.
Crossings and bridge care 12
causewayA raised road or track across water or wet ground. Earth, stone, wood and concrete have all been used to build causeways. The Sweet Track in England, a wooden one, dates from the Neolithic age and is among the earliest known.
culvertA pipe or channel that lets water pass under a road. A badly designed culvert can block the way for fish moving up and down a stream.
ferryA vessel that shuttles riders from shore to shore. A ferry service costs far less to set up than a bridge or a tunnel.
fordA spot where a stream is low enough to walk through. A ford may be natural or built, and it can be impassable when the water is high.
infrastructureShared works such as roads, sewers and power lines. It is everything a country, city or area needs for its homes and businesses to function, airports, railways and water supply included.
inspectionA careful check for damage or wear. In the United States, the National Bridge Inspection Standards cover the safety inspection of highway bridges on public roads. The first version was published in 1971.
natural archA bridge of rock shaped by nature, not by people. Many form where the sea, a river or the weather wears away the rock of a cliff. Rainbow Bridge in Utah is one of the largest in the world.
obstacleWhatever stands between a traveler and the far side. The obstacle to be crossed, such as a river, a canyon, another road or railroad tracks, is the main thing that decides which kind of bridge is best.
pedestrianAnyone who is getting about on their own two feet. A bridge built for pedestrians is called a footbridge.
stepping stonesStones set in a stream for crossing it on foot. People probably crossed streams on stepping stones and on logs long before they built anything else.
tunnelA way cut through earth or rock, closed in overhead. The world's longest railway tunnel is the Gotthard Base Tunnel in Switzerland.
wildlife crossingA bridge or tunnel built so animals can cross a road. Crossings range from green bridges for herds of large animals to small tunnels for amphibians and reptiles.
How this list was compiled: Term list chosen for this site on 2026-10-12. Each meaning is written in our own words and was checked that day against the article on the term in the English Wikipedia (https://en.wikipedia.org/), whose text is under the Creative Commons Attribution-ShareAlike license: Bridge, Span (engineering), Deck (bridge), Pier (bridge structure), Abutment, Structural load, Beam bridge, Arch bridge, Truss bridge, Suspension bridge, Cable-stayed bridge, Cantilever bridge, Cantilever, Tension (physics), Compression (physics), Gravity, Structure, Mechanical equilibrium, Factor of safety, Ductility, Brittleness, Corrosion, Rust, Bedrock, Causeway, Culvert, Tunnel, Ferry, Ford (crossing), Stepping stones, Natural arch, Rainbow Bridge National Monument, Wildlife crossing, Infrastructure and Tacoma Narrows Bridge (1940). Force, obstacle, pedestrian, footbridge, strength and inspection were read in Wiktionary, the free dictionary (https://en.wiktionary.org/). Force, tension and compression, the kinds of load, the strength of materials, foundations and the obstacle a bridge crosses were checked a second time against TeachEngineering of the University of Colorado Boulder (https://www.teachengineering.org/lessons/view/cub_brid_lesson01, Bridge Types: Tensile and Compressive Forces; https://www.teachengineering.org/lessons/view/cub_brid_lesson02, Designing Bridges; https://www.teachengineering.org/lessons/view/cub_brid_lesson03, A Good Foundation); beam, arch, truss, suspension and cantilever bridges and their spans against Building Big of the Public Broadcasting Service (https://www.pbs.org/wgbh/buildingbig/bridge/basics.html, Bridge Basics); bridge inspection against the Federal Highway Administration of the U.S. Department of Transportation (https://www.fhwa.dot.gov/bridge/nbis.cfm, National Bridge Inspection Standards). The fact after each meaning is from the same pages. Licence: own work
How it works
This bridge vocabulary worksheet has bridge, span, deck, pier, abutment and load to match to their meanings, with six kinds of bridge: beam, arch, truss, suspension, cable-stayed and cantilever. An answer key follows the sheet.
Read the full guide
Forces and materials
Set opens on Bridges and their parts. The second set, for the lesson before a class builds and loads its own bridges, has force, tension, compression, gravity, strength, structure, equilibrium, safety factor, ductile, brittle, corrosion and bedrock.
Crossings and bridge care
The third set has obstacle, causeway, culvert, tunnel, ferry, ford, stepping stones, natural arch, wildlife crossing, infrastructure, inspection and pedestrian.
Keystone, girder, trestle, viaduct and the truss shapes by name are on the bridge word search.
Questions and answers
What is the difference between a suspension bridge and a cable-stayed bridge?
The path of the cables. On a suspension bridge the deck hangs by vertical hangers from main cables that run from tower to tower. On a cable-stayed bridge the cables run straight from the towers to the deck.
How long can a suspension bridge be?
Longer than any other kind of bridge: 2,000 to 7,000 feet (about 600 to 2,100 meters) between its towers. The longest main span in the world is that of the 1915 Çanakkale Bridge in Turkey, which joins Europe and Asia.
Why did the Tacoma Narrows Bridge collapse?
Wind. On November 7, 1940, four months after it opened, a 40-mile-an-hour wind set the deck of this suspension bridge in Washington State twisting in a motion called flutter, which grew until the main span tore apart.