5,208 articles
Rogfast
Rogfast is a 26.7 km subsea road tunnel under construction in Rogaland, Norway, carrying the E39 under the Boknafjorden; when it opens in 2033 it will be the world's longest and deepest subsea road tunnel.
Rogue River Basin Project
The Rogue River Basin Project is a federal irrigation and hydropower project in southwestern Oregon, whose Talent Division, built by the Bureau of Reclamation, was authorized in 1954.
Rogun Dam
Rogun Dam is a 335-meter dam under construction on the Vakhsh River in Tajikistan, expected to become the world's tallest when completed, with a 3,600 MW hydropower plant.
Roller-compacted concrete
Roller-compacted concrete (RCC), also known as rollcrete, is a dry, zero-slump concrete placed in layers with earthmoving equipment and compacted by vibratory rollers, widely used for concrete gravity dams and heavy-duty pavements.
Roller-compacted concrete dam
A roller-compacted concrete dam is a concrete gravity dam built by placing dry concrete in horizontal layers compacted with vibratory rollers, cutting costs 25 to 40 percent.
Rolling lift
Rolling lift is a bascule bridge where the span rolls along a curved track rather than pivoting, as in the design patented by William Scherzer in 1893.
Roman aqueduct
A Roman aqueduct was a channel, tunnel, or pipeline that carried water by gravity from springs to Roman towns, chiefly for public baths and drinking fountains.
Roman bridge
Roman bridge: stone-arch bridges built by Roman engineers along the empire's road network, also called pontes. Over 300 major examples, built mainly in the 1st century BC and early 2nd century AD, using the voussoir arch, concrete, and cofferdam foundations; Alcántara, Mérida, and Trajan's Danube bridge are famous cases.
Roman bridge at Buonfornello
Roman bridge at Buonfornello (Ponte Grande), an ancient stone bridge of seven piers and eight arches crossing the Imera river in Sicily on the via Valeria, probably 1st century BC, collapsed by the 16th century and eliminated in 1960-70 river works.
Roman bridge at Habitancum
Roman bridge at Habitancum (Risingham), Northumberland: Dere Street's crossing of the River Rede beside the Habitancum fort (HER 7947). Bridge-works noted by Hodgson in 1824; post-Roman river action removed most remains.
Roman Bridge at Moulin de Boisseron
Roman Bridge at Moulin de Boisseron (Pont romain de Boisseron): 1st-century AD, Tiberian-era Roman road bridge over the Bénovie at Boisseron, Hérault, France; five semicircular arches, 50.60 m long, widened 1833-36, classified monument historique 2008.
Roman bridge at Valeriana
The Roman bridge at Valeriana was a Roman bridge over the Danube at the ford between Dolni Vadin, Bulgaria, and Grojdibodu, Romania, built under Emperor Domitian during the Dacian war.
Roman bridge of San Vito
Roman bridge of San Vito (Ponte romano di San Vito, Pontaccio): ruined Roman bridge near Rimini, Italy, carrying the Via Emilia over the Uso river, probably Augustan, tied to the Rubicon question and redeveloped in 2022.
Roman bridge, Mérida
Roman bridge, Mérida (Puente Romano sobre el Guadiana): Augustan-era Roman bridge at Augusta Emerita, Spain; 792 m, 60 semicircular arches, granite ashlar over concrete, pedestrian since 1993, UNESCO-listed.
Roman bridge, Pietralunga di Paternò
Roman bridge, Pietralunga di Paternò (Ponte romano di Pietralunga): ruined two-arched Roman lava-stone bridge over the Simeto at Paternò, Catania, Sicily; about 23 m long, 4.15 m wide, on the Catania-Centuripe-Enna road.
Roman concrete
Roman concrete (opus caementicium): lime-and-volcanic-ash building material with coarse caementa aggregates, documented by Vitruvius, used for the Pantheon dome and Roman harbors; distinct from Portland cement by pozzolanic C-A-S-H chemistry and self-healing lime clasts.
Roman dams
Roman dams are water-retaining structures built across the Roman and early Byzantine world from the 1st century BC, concentrated in Spain, North Africa, and the Near East.
Roman irrigation in North Africa
Roman irrigation in North Africa was the system of dams, terraces, cisterns, and foggaras that made the arid region a major grain and olive supplier to Rome.
Roman irrigation in Spain
Roman irrigation in Spain comprised dam-fed canals, estate waterworks, and legally organized irrigation communities in Hispania, distinct from urban aqueducts, with channels still functioning today.
Roman irrigation in the Levant
Roman irrigation in the Levant was a set of runoff-harvesting, floodwater-farming, and qanat systems in the Negev, southern Jordan, and Syria, from the first century BCE to the eighth century CE.
Roman roads
Roman roads were the paved routes built by the Roman state from 312 BCE, when the Via Appia linked Rome to Capua, eventually spanning nearly 300,000 kilometers.
Roman villa
Roman villa: rural estate center combining elite residence (pars urbana) and farm (pars rustica), a market-oriented farming institution spread across the western Roman Empire, later revived by Renaissance architects like Palladio.
Romanesque architecture
Romanesque architecture is the style of building that prevailed in western Europe from the late 10th to the 12th century, characterized by round arches and thick walls.
Ronald Rael
Ronald Rael is an American architect, author, and design technologist at UC Berkeley, known for the Teeter-Totter Wall at the US–Mexico border and 3D-printed earthen architecture.
Ronald Reagan Building and International Trade Center
Ronald Reagan Building and International Trade Center (RRB/ITC), Washington DC's largest structure at 3.1 million sq ft on Pennsylvania Avenue; GSA-owned, TCMA-operated federal building and official World Trade Center, opened May 5, 1998.
Ronan Point
Ronan Point was a 22-storey tower block of flats in Canning Town, London, built of prefabricated concrete panels. A 1968 gas explosion collapsed its corner, killing five, and prompted new building-code rules against progressive collapse.
Roof
A roof is the construction covering the upper part of a building to exclude rain, snow, and sun, combining structure, weatherproofing, and, increasingly, energy and climate functions.
Roof garden
A roof garden, or rooftop garden, is a garden built on a building's roof, either in containers or as an engineered green roof that reduces urban stormwater runoff.
Roof shingle
A roof shingle, also called a roofing shingle, is a thin piece of wood, asphalt, slate, metal, or concrete laid in overlapping rows to shed rainwater.
Room for the River (Netherlands)
Room for the River (Ruimte voor de Rivier) is a Dutch flood-protection program that gives rivers more space rather than raising dikes, running from 2006 to 2019.