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54-541: Heavy equipment has been used since at least the 1st century BC, when the ancient Roman engineer Vitruvius described a crane powered by human or animal labor in De architectura . Heavy equipment functions through the mechanical advantage of a simple machine that multiplies the ratio between input force applied and force exerted, easing and speeding tasks which often could otherwise take hundreds of people and many weeks' labor. Some such equipment uses hydraulic drives as

108-552: A gear train cutting rectangular blocks. Further crank and connecting rod mechanisms, without gear train, are archaeologically attested for the 6th-century AD water-powered stone sawmills at Gerasa , Jordan , and Ephesus , Turkey. Literary references to water-powered marble saws in Trier , now Germany , can be found in Ausonius 's late 4th-century AD poem Mosella . They attest a diversified use of water-power in many parts of

162-510: A quay or yard on a rail track. Instead of a hook, they are equipped with a specialized handling tool called a spreader . The spreader can be lowered on top of a container and locks onto the container's four locking points ("corner castings") using a twistlock mechanism. Cranes normally transport a single container at once, but some newer cranes have the capability to pick up two to four 20-foot containers at once. There are two common types of container handling gantry crane: high profile, where

216-539: A city of bricks to a city of marble. The Romans had originally brought marble over from Greece, but later found their own quarries in northern Italy. Cement was made of hydrated lime (calcium oxide) mixed with sand and water. The Romans discovered that substituting or supplementing the sand with a pozzolanic additive , such as volcanic ash, would produce a very hard cement, known as hydraulic mortar or hydraulic cement . They used it widely in structures such as buildings, public baths and aqueducts, ensuring their survival into

270-623: A conveyance, usually a wheelbarrow , or a cart or wagon drawn by a draft animal . In antiquity, an equivalent of the hand shovel or hoe and head basket—and masses of men—were used to move earth to build civil works. Builders have long used the inclined plane , levers, and pulleys to place solid building materials, but these labor-saving devices did not lend themselves to earthmoving, which required digging, raising, moving, and placing loose materials. The two elements required for mechanized earthmoving, then as now, were an independent power source and off-road mobility, neither of which could be provided by

324-576: A country where gold mining developed on a very large scale in the early part of the first century AD, such as at Las Medulas . Roman bridges were among the first large and lasting bridges ever built. They were built with stone, employing the arch as basic structure. Most utilized concrete as well. Built in 142 BC, the Pons Aemilius , later named Ponte Rotto (broken bridge) is the oldest Roman stone bridge in Rome, Italy. The biggest Roman bridge

378-549: A fact attested both by Vitruvius (in De architectura ) and by Pliny the Elder (in Naturalis Historia ). The largest complex of water wheels existed at Barbegal near Arles , where the site was fed by a channel from the main aqueduct feeding the town. It is estimated that the site comprised sixteen separate overshot water wheels arranged in two parallel lines down the hillside. The outflow from one wheel became

432-872: A growing concern for heavy equipment manufacturers with manufacturers beginning research and technology acquisition. A number of companies are currently developing ( Caterpillar and Bobcat ) or have launched ( Built Robotics ) commercial solutions to the market. These subdivisions, in this order, are the standard heavy equipment categorization. Tractor Grader Excavator Backhoe Timber Pipelayer Scraper Mining Articulated Compactor Loader Track loader Skid-steer loader Material handler Paving Underground Hydromatic tool Hydraulic machinery Highway Heavy equipment requires specialized tires for various construction applications. While many types of equipment have continuous tracks applicable to more severe service requirements, tires are used where greater speed or mobility

486-622: A large expense on any construction project, careful consideration should be given to prevent excessive wear or damage. A heavy equipment operator drives and operates heavy equipment used in engineering and construction projects. Typically only skilled workers may operate heavy equipment, and there is specialized training for learning to use heavy equipment. Much publication about heavy equipment operators focuses on improving safety for such workers. The field of occupational medicine researches and makes recommendations about safety for these and other workers in safety-sensitive positions. Due to

540-422: A long history; the ancient Roman engineer Vitruvius (1st century BCE) gave descriptions of heavy equipment and cranes in ancient Rome in his treatise De architectura . The pile driver was invented around 1500. The first tunnelling shield was patented by Marc Isambard Brunel in 1818. Until the 19th century and into the early 20th century heavy machines were drawn under human or animal power. With

594-444: A primary source of motion. The word plant , in this context, has come to mean any type of industrial equipment, including mobile equipment (e.g. in the same sense as powerplant ). However, plant originally meant "structure" or "establishment" – usually in the sense of factory or warehouse premises; as such, it was used in contradistinction to movable machinery, often in the phrase "plant and equipment". The use of heavy equipment has

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648-591: A similar way. Engineering was also institutionally ingrained in the Roman military, who constructed forts, camps, bridges, roads, ramps, palisades, and siege equipment amongst others. One of the most notable examples of military bridge-building in the Roman Republic was Julius Caesar's bridge over the Rhine River . This bridge was completed in only ten days by a dedicated team of engineers. Their exploits in

702-489: A steep hill. The site thus resembles Barbegal , although excavations in the late 1990s suggest that they may have been undershot rather than overshot in design. The mills were in use in 537 AD when the Goths besieging the city cut off their water supply. However they were subsequently restored and may have remained in operation until at least the time of Pope Gregory IV (827–44). Many other sites are reported from across

756-456: A wave of water from a tank to scour away the soil and so reveal the bedrock with any veins exposed to sight. They used the same method (known as hushing ) to remove waste rock, and then to quench hot rocks weakened by fire-setting . Such methods could be very effective in opencast mining, but fire-setting was very dangerous when used in underground workings. They were made redundant with the introduction of explosives , although hydraulic mining

810-420: Is determined by the design vessel and local environment. Container cranes are generally classified by their lifting capacity and the size of the container ships they can load and unload. Smaller container cranes, such as straddle carriers , are used at railway sidings to transfer containers from flatcars and well cars to semi-trailers or vice versa. Both the rolling stock and the trailers may pass under

864-449: Is driven by an operator who sits in a cabin suspended from the trolley. The trolley runs along rails located on the top or sides of the boom and girder. The operator runs the trolley over the ship to lift the cargo, usually containers. Once the spreader locks onto the container, the container is lifted, moved over the dock, and placed on a truck chassis (trailer) to be taken to the storage yard. The crane also lifts containers from chassis on

918-667: Is required. An understanding of what equipment will be used for during the life of the tires is required for proper selection. Tire selection can have a significant impact on production and unit cost. There are three types of off-the-road tires, transport for earthmoving machines, work for slow moving earthmoving machines, and load and carry for transporting as well as digging. Off-highway tires have six categories of service C compactor, E earthmover, G grader, L loader, LS log-skidder and ML mining and logging. Within these service categories are various tread types designed for use on hard-packed surface, soft surface and rock. Tires are

972-514: Is still used on alluvial tin ores. They were also used to produce a controlled supply to wash the crushed ore. It is highly likely that they also developed water-powered stamp mills to crush hard ore, which could be washed to collect the heavy gold dust. At alluvial mines, they applied their hydraulic mining methods on a vast scale, such as Las Medulas in north-west Spain. Traces of tanks and aqueducts can be found at many other early Roman mines. The methods are described in great detail by Pliny

1026-504: The Dacian wars under Trajan in the early 2nd century AD are recorded on Trajan's column in Rome. The army was also closely involved in gold mining and probably built the extensive complex of leats and cisterns at the Roman gold mine of Dolaucothi in Wales shortly after conquest of the region in 75 AD. Water wheel technology was developed to a high level during the Roman period,

1080-461: The Roman Empire , although many remain unexcavated. Container crane A container crane (also container handling gantry crane or ship-to-shore crane ) is a type of large dockside gantry crane found at container terminals for loading and unloading intermodal containers from container ships . Container cranes consist of a supporting framework that can traverse the length of

1134-628: The Roman Empire . A complex of mills also existed on the Janiculum in Rome fed by the Aqua Traiana . The Aurelian Walls were carried up the hill apparently to include the water mills used to grind grain towards providing bread flour for the city. The mill was thus probably built at the same time as or before the walls were built by the emperor Aurelian (reigned 270–275 AD). The mills were supplied from an aqueduct, where it plunged down

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1188-615: The Subiaco dams , two of which fed Anio Novus , the largest aqueduct supplying Rome. One of the Subiaco dams was reputedly the highest ever found or inferred. They built 72 dams in Spain, such as those at Mérida , and many more are known across the empire. At one site, Montefurado in Galicia , they appear to have built a dam across the river Sil to expose alluvial gold deposits in the bed of

1242-586: The pavimentum , was one inch thick and made of mortar. Above this were four strata of masonry. The layer directly above the pavimentum was called the statumen . It was one foot thick, and was made of stones bound together by cement or clay. Above that, there was the rudens , which was made of ten inches of rammed concrete. The next layer, the nucleus , was made of twelve to eighteen inches of successively laid and rolled layers of concrete. Summa crusta of silex or lava polygonal slabs, one to three feet in diameter and eight to twelve inches thick, were laid on top of

1296-427: The Elder in his Naturalis Historia . He also described deep mining underground, and mentions the need to dewater the workings using reverse overshot water-wheels , and actual examples have been found in many Roman mines exposed during later mining attempts. The copper mines at Rio Tinto were one source of such artefacts, where a set of 16 was found in the 1920s. They also used Archimedean screws to remove water in

1350-560: The Romans, the Colosseum exhibits the arches and curves commonly associated with Roman buildings. The Pantheon in Rome still stands a monument and tomb, and the Baths of Diocletian and the Baths of Caracalla are remarkable for their state of preservation, the former still possessing intact domes . Such massive public buildings were copied in numerous provincial capitals and towns across

1404-546: The advent of portable steam-powered engines the drawn machine precursors were reconfigured with the new engines, such as the combine harvester . The design of a core tractor evolved around the new steam power source into a new machine core traction engine , that can be configured as the steam tractor and the steamroller . During the 20th century, internal-combustion engines became the major power source of heavy equipment. Kerosene and ethanol engines were used, but today diesel engines are dominant. Mechanical transmission

1458-680: The base. Smaller container cranes are also used at break-of-gauge transloading facilities . A Panamax crane can fully load and unload containers from a panamax class container ship capable of passing through the Panama Canal. A "post-Panamax" crane can load and unload containers from a container ship too large (too wide) to pass through the Panama Canal . The largest modern container cranes are classified as "super-post-Panamax". A modern container crane capable of lifting two 20-foot (6.1 m) long containers at once (end to end) under

1512-451: The boom is hinged at the waterside of the crane structure and lifted in the air to clear the ships for navigation, and low profile, where the boom is shuttled toward and over the ship to allow the trolley to load and discharge containers. Low-profile cranes are used where they may be in the flight path of aircraft, such as where a container terminal is located close to an airport. The type of crane selected in container terminal design process

1566-598: The building of reservoirs to hold the water needed at the minehead. It is known that they were also capable of building and operating mining equipment such as crushing mills and dewatering machines. Large diameter vertical wheels of Roman vintage, for raising water, have been excavated from the Rio Tinto mines in Southwestern Spain. They were closely involved in exploiting gold resources such as those at Dolaucothi in south west Wales and in north-west Spain,

1620-400: The bulldozer. The largest engineering vehicles and mobile land machines are bucket-wheel excavators , built since the 1920s. Until almost the twentieth century, one simple tool constituted the primary earthmoving machine: the hand shovel —moved with animal and human powered, sleds, barges, and wagons. This tool was the principal method by which material was either sidecast or elevated to load

1674-418: The city. Roman engineers used inverted siphons to move water across a valley if they judged it impractical to build a raised aqueduct. The Roman legions were largely responsible for building the aqueducts. Maintenance was often done by slaves. The Romans were among the first civilizations to harness the power of water. They built some of the first watermills outside of Greece for grinding flour and spread

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1728-473: The crane or electric power from the dock. The most common is by electric power from the dock (also known as shore power). The voltage required may range from 4,000 to 13,200 volts . Cranes were used in harbors starting in the Middle Ages (see crane: harbor usage and list of historical harbour cranes ). Modern inter-modal containerization emerged in the mid-1950s from transport strategies developed in

1782-430: The dock to load them onto the ship. Straddle carriers , sidelifts , reach stackers , or container lorries then manoeuvre underneath the crane base and collect the containers, rapidly moving them away from the dock and to a storage yard. Flatcars or well cars may also be loaded directly beneath the crane base. A crane can be powered by two types of power supply : a diesel engine–driven generator located on top of

1836-403: The empire, and the general principles behind their design and construction are described by Vitruvius writing at the turn of millennium in his monumental work De architectura . The technology developed for the baths was especially impressive, especially the widespread use of the hypocaust for one of the first types of central heating developed anywhere. That invention was used not just in

1890-464: The equipment while minor repairs are costed to a project. Another common costing strategy is to cost all repairs to the equipment and only frequently replaced wear items are excluded from the equipment cost. Many firms keep their costing structure closely guarded as it can impact the bidding strategies of their competition. In a company with multiple semi-independent divisions, the equipment department often wants to classify all repairs as "minor" and charge

1944-471: The equipment. These costs are as follows: The biggest distinction from a cost standpoint is if a repair is classified as a major repair or a minor repair . A major repair can change the depreciable equipment value due to an extension in service life , while a minor repair is normal maintenance . How a firm chooses to cost major and minor repairs vary from firm to firm depending on the costing strategies being used. Some firms will charge only major repairs to

1998-482: The gold mines at Dolaucothi in west Wales . Masonry dams were common in North Africa for providing a reliable water supply from the wadis behind many settlements. The buildings and architecture of Ancient Rome were impressive. The Circus Maximus , for example, was large enough to be used as a stadium. The Colosseum also provides an example of Roman architecture at its finest. One of many stadiums built by

2052-430: The input to the next one down in the sequence. Twelve kilometers north of Arles, at Barbegal, near Fontvieille , where the aqueduct arrived at a steep hill, the aqueduct fed a series of parallel water wheels to power a flourmill . There are two aqueducts which join just north of the mill complex, and a sluice which enabled the operators to control the water supply to the complex. There are substantial masonry remains of

2106-503: The large public buildings, but spread to domestic buildings such as the many villas which were built across the Empire. The most common materials used were brick , stone or masonry , cement , concrete and marble . Brick came in many different shapes. Curved bricks were used to build columns, and triangular bricks were used to build walls. Marble was mainly a decorative material. Augustus once boasted that he had turned Rome from

2160-492: The modern era. The Romans were the first to exploit mineral deposits using advanced technology, especially the use of aqueducts to bring water from great distances to help operations at the pithead. Their technology is most visible at sites in Britain such as Dolaucothi where they exploited gold deposits with at least five long aqueducts tapping adjacent rivers and streams. They used the water to prospect for ore by unleashing

2214-456: The river. The site is near the spectacular Roman gold mine of Las Medulas . Several earthen dams are known from Britain, including a well-preserved example from Roman Lanchester, Longovicium , where it may have been used in industrial-scale smithing or smelting , judging by the piles of slag found at this site in northern England. Tanks for holding water are also common along aqueduct systems, and numerous examples are known from just one site,

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2268-764: The rudens. The final upper surface was made of concrete or well-smoothed and fitted flint. Generally, when a road encountered an obstacle, the Romans preferred to engineer a solution to the obstacle rather than redirecting the road around it: bridges were constructed over all sizes of waterway; marshy ground was handled by the construction of raised causeways with firm foundations; hills and outcroppings were frequently cut or tunneled through rather than avoided (the tunnels were made with rectangle hard rock block). A thousand cubic metres (260,000 US gal) of water were brought into Rome by eleven different aqueducts each day. Per capita water usage in ancient Rome matched that of modern-day cities like New York City or modern Rome. Most water

2322-571: The simplest is the straight-line method. The annual depreciation is constant, reducing the equipment value annually. The following are simple equations paraphrased from the Peurifoy & Schexnayder text: m = some year in the future N = equipment useful life (years) and D n = Annual depreciation amount Book value (BV) in year m example: N = 5 purchase price = $ 350,000 m = 3 years from now For an expense to be classified as an operating cost, it must be incurred through use of

2376-431: The small profit margins on construction projects it is important to maintain accurate records concerning equipment utilization, repairs and maintenance. The two main categories of equipment costs are ownership cost and operating cost . To classify as an ownership cost an expense must have been incurred regardless of if the equipment is used or not. These costs are as follows: Depreciation can be calculated several ways,

2430-501: The technology for constructing watermills throughout the Mediterranean region. A famous example occurs at Barbegal in southern France, where no fewer than 16 overshot mills built into the side of a hill were worked by a single aqueduct, the outlet from one feeding the mill below in a cascade. They were also skilled in mining, building aqueducts needed to supply equipment used in extracting metal ores, e.g. hydraulic mining , and

2484-596: The technology of that time. Container cranes were used from the 1950s and onwards, and made containerization possible. Nowadays such is the importance of this machinery, some transport companies have developed specific equipment to transport heavy construction equipment to and from sites. Most of the major equipment manufacturers such as Caterpillar, Volvo, Liebherr, and Bobcat have released or have been developing fully or partially electric-powered heavy equipment. Commercially-available models and R&D models were announced in 2019 and 2020. Robotics and autonomy has been

2538-541: The telescopic spreader will generally have a rated lifting capacity of 65 tonnes. Some new cranes have a 120-tonne load capacity, enabling them to lift up to four 20-foot (6.1 m) or two 40-foot (12 m) containers. Cranes capable of lifting six 20-foot containers have also been designed. Post-Panamax cranes weigh approximately 800–900 tonnes, while the newer-generation super-post-Panamax cranes can weigh 1,600–2,000 tonnes. The largest Super-post-Panamax cranes have an outreach of 26 container rows. The crane

2592-448: The water channels and foundations of the individual mills, together with a staircase rising up the hill upon which the mills are built. The mills apparently operated from the end of the 1st century until about the end of the 3rd century. The capacity of the mills has been estimated at 4.5 tons of flour per day, sufficient to supply enough bread for the 12,500 inhabitants occupying the town of Arelate at that time. The Hierapolis sawmill

2646-572: The work to a job – therefore improving their 'profit' from the equipment. Die-cast metal promotional scale models of heavy equipment are often produced for each vehicle to give to prospective customers. These are typically in 1:50 scale . The popular manufacturers of these models are Conrad and NZG in Germany, even for US vehicles. Roman engineering The ancient Romans were famous for their advanced engineering accomplishments. Technology for bringing running water into cities

2700-419: Was Trajan's bridge over the lower Danube, constructed by Apollodorus of Damascus , which remained for over a millennium the longest bridge to have been built both in terms of overall and span length. They were normally at least 18 meters above the body of water. An example of temporary military bridge construction is the two Caesar's Rhine bridges . The Romans built many dams for water collection, such as

2754-427: Was a Roman water-powered stone saw mill at Hierapolis , Asia Minor (modern-day Turkey ). Dating to the second half of the 3rd century AD, the sawmill is the earliest known machine to combine a crank with a connecting rod . The watermill is shown on a raised relief on the sarcophagus of Marcus Aurelius Ammianos, a local miller . A waterwheel fed by a mill race is shown powering two frame saws via

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2808-531: Was developed in the east, but transformed by the Romans into a technology inconceivable in Greece. The architecture used in Rome was strongly influenced by Greek and Etruscan sources. Roman roads were constructed to be immune to floods and other environmental hazards. Some roads built by the Romans are still in use today. There were several variations on a standard Roman road. Most of the higher quality roads were composed of five layers. The bottom layer, called

2862-404: Was for public use, such as baths and sewers. De aquaeductu is the definitive two volume treatise on 1st century aqueducts of Rome, written by Frontinus . The aqueducts could stretch from 10–100 km (10–60 mi) long, and typically descended from an elevation of 300 m (1,000 ft) above sea level at the source, to 100 m (330 ft) when they reached the reservoirs around

2916-647: Was in many cases replaced by hydraulic machinery. The early 20th century also saw new electric-powered machines such as the forklift . Caterpillar Inc. is a present-day brand from these days, starting out as the Holt Manufacturing Company . The first mass-produced heavy machine was the Fordson tractor in 1917. The first commercial continuous track vehicle was the 1901 Lombard Steam Log Hauler . The use of tracks became popular for tanks during World War I , and later for civilian machinery like

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