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59-424: A wharf commonly comprises a fixed platform, often on pilings . Commercial ports may have warehouses that serve as interim storage: where it is sufficient a single wharf with a single berth constructed along the land adjacent to the water is normally used; where there is a need for more capacity multiple wharves, or perhaps a single large wharf with multiple berths, will instead be constructed, sometimes projecting over

118-402: A continuous flight augering (CFA) pile, is formed by drilling into the ground with a hollow stemmed continuous flight auger to the required depth or degree of resistance. No casing is required. A cement grout mix is then pumped down the stem of the auger. While the cement grout is pumped, the auger is slowly withdrawn, conveying the soil upward along the flights. A shaft of fluid cement grout

177-441: A foundation is the element of a structure which connects it to the ground or more rarely, water (as with floating structures ), transferring loads from the structure to the ground. Foundations are generally considered either shallow or deep . Foundation engineering is the application of soil mechanics and rock mechanics ( geotechnical engineering ) in the design of foundation elements of structures. Foundations provide

236-449: A 4.74-meter-diameter monopile footing in ocean depths up to 16 meters of water. A floating foundation is one that sits on a body of water, rather than dry land. This type of foundation is used for some bridges and floating buildings. Foundations are designed to have an adequate load capacity depending on the type of subsoil/rock supporting the foundation by a geotechnical engineer , and the footing itself may be designed structurally by

295-402: A Continuous Flight Auger rig but using smaller, more lightweight equipment. This piling method is fast, cost-effective and suitable for the majority of ground types. In drilled pier foundations, the piers can be connected with grade beams on which the structure sits, sometimes with heavy column loads bearing directly on the piers. In some residential construction, the piers are extended above

354-430: A continuous barrier in the ground. The main application of sheet piles is in retaining walls and cofferdams erected to enable permanent works to proceed. Normally, vibrating hammer, t-crane and crawle drilling are used to establish sheet piles. Soldier piles, also known as king piles or Berlin walls, are constructed of steel H sections spaced about 2 to 3 m apart and are driven or drilled prior to excavation. As

413-463: A crisscross of timbers or steel beams in concrete is called grillage. Perhaps the simplest foundation is the padstone, a single stone which both spreads the weight on the ground and raises the timber off the ground. Staddle stones are a specific type of padstone. Dry stone and stones laid in mortar to build foundations are common in many parts of the world. Dry laid stone foundations may have been painted with mortar after construction. Sometimes

472-417: A displacement pile (like Olivier piles ) may provide the cost efficiency of an augercast pile and minimal environmental impact. In ground containing obstructions or cobbles and boulders, augercast piles are less suitable as refusal above the design pile tip elevation may be encountered. Small Sectional Flight Auger piling rigs can also be used for piled raft foundations. These produce the same type of pile as

531-420: A failure of the foundation system. Vibrated stone columns are a ground improvement technique where columns of coarse aggregate are placed in soils with poor drainage or bearing capacity to improve the soils. Specific to marine structures, hospital piles (also known as gallow piles) are built to provide temporary support to marine structure components during refurbishment works. For example, when removing

590-412: A large hollow steel pile, of some 4 m in diameter with approximately 50mm thick walls, some 25 m deep into the seabed, through a 0.5 m layer of larger stone and gravel to minimize erosion around the pile. A transition piece (complete with pre-installed features such as boat-landing arrangement, cathodic protection , cable ducts for sub-marine cables, turbine tower flange, etc.) is attached to

649-515: A long time below the groundwater level. In 1648, the Royal Palace of Amsterdam was constructed on 13,659 timber piles that still survive today since they were below groundwater level. Timber that is to be used above the water table can be protected from decay and insects by numerous forms of wood preservation using pressure treatment ( alkaline copper quaternary (ACQ), chromated copper arsenate (CCA), creosote , etc.). Splicing timber piles

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708-615: A river pontoon, the brow will be attached to hospital pile to support it. They are normal piles, usually with a chain or hook attachment. Piled walls can be drivene or bored. They provide special advantages where available working space dictates and open cut excavation not feasible. Both methods offer technically effective and offer a cost efficient temporary or permanent means of retaining the sides of bulk excavations even in water bearing strata. When used in permanent works, these walls can be designed to resist vertical loads in addition lateral load from retaining soil. Construction of both methods

767-419: A shallow foundation, such as for a skyscraper . Some of the common reasons are very large design loads, a poor soil at shallow depth, or site constraints like property lines . There are different terms used to describe different types of deep foundations including the pile (which is analogous to a pole), the pier (which is analogous to a column ), drilled shafts, and caissons . Piles are generally driven into

826-448: A single, generally large-diameter, structural element embedded into the earth to support all the loads (weight, wind, etc.) of a large above-surface structure. Many monopile foundations have been used in recent years for economically constructing fixed-bottom offshore wind farms in shallow-water subsea locations. For example, a single wind farm off the coast of England went online in 2008 with over 100 turbines, each mounted on

885-453: A straight-shaft pile. These piles are suited for expansive soils which are often subjected to seasonal moisture variations, or for loose or soft strata. They are used in normal ground condition also where economics are favorable. Under reamed piles foundation is used for the following soils:- 1. Under reamed piles are used in black cotton soil: This type of soil expands when it comes in contact with water and contraction occurs when water

944-462: A tripod rig to install piles is one of the more traditional ways of forming piles. Although unit costs are generally higher than with most other forms of piling, it has several advantages which have ensured its continued use through to the present day. The tripod system is easy and inexpensive to bring to site, making it ideal for jobs with a small number of piles. Sheet piling is a form of driven piling using thin interlocking sheets of steel to obtain

1003-496: Is a barrier built under ground using a mix of bentonite and water to prevent the flow of groundwater. A trench that would collapse due to the hydraulic pressure in the surrounding soil does not collapse as the slurry balances the hydraulic pressure. These are essentially variations of in situ reinforcements in the form of piles (as mentioned above), blocks or larger volumes. Cement, lime/quick lime, flyash, sludge and/or other binders (sometimes called stabilizer) are mixed into

1062-409: Is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. A pile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site . There are many reasons that a geotechnical engineer would recommend a deep foundation over

1121-412: Is also not possible to extend the wall beyond the bottom of the excavation, and dewatering is often required. Screw piles , also called helical piers and screw foundations , have been used as foundations since the mid 19th century in screw-pile lighthouses . Screw piles are galvanized iron pipe with helical fins that are turned into the ground by machines to the required depth. The screw distributes

1180-465: Is common with steel piles, though concrete piles can be spliced with mechanical and other means. Driving piles, as opposed to drilling shafts, is advantageous because the soil displaced by driving the piles compresses the surrounding soil, causing greater friction against the sides of the piles, thus increasing their load-bearing capacity . Driven piles are also considered to be "tested" for weight-bearing ability because of their method of installation; thus

1239-463: Is formed to ground level. Reinforcement can be installed. Recent innovations in addition to stringent quality control allows reinforcing cages to be placed up to the full length of a pile when required. Augercast piles cause minimal disturbance and are often used for noise-sensitive and environmentally-sensitive sites. Augercast piles are not generally suited for use in contaminated soils, because of expensive waste disposal costs. In cases such as these,

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1298-420: Is more environmentally friendly is to use screw piles . Screw pile installations have also extended to residential applications, with many homeowners choosing a screw pile foundation over other options. Some common applications for helical pile foundations include wooden decks, fences, garden houses, pergolas, and carports. Used to transfer the load of a structure down through the upper weak layer of topsoil to

1357-414: Is often used when the sides of the borehole are likely to slough off before concrete is poured. For end-bearing piles, drilling continues until the borehole has extended a sufficient depth (socketing) into a sufficiently strong layer. Depending on site geology, this can be a rock layer , or hardpan, or other dense, strong layers. Both the diameter of the pile and the depth of the pile are highly specific to

1416-426: Is removed. So that cracks appear in the construction done on such clay. An under reamed pile is used in the base to remove this defect. 2. Under reamed piles are used in low bearing capacity Outdated soil (filled soil) 3.Under reamed piles are used in sandy soil when water table is high. 4. Under reamed piles are used, Where lifting forces appear at the base of foundation. An augercast pile, often known as

1475-443: Is simply there to ensure that the two pieces follow each other during driving. If uplift capacity is required, the splice can incorporate bolts, coach screws, spikes or the like to give it the necessary capacity. Cast iron may be used for piling. These may be ductile . Pipe piles are a type of steel driven pile foundation and are a good candidate for inclined ( battered ) piles. Foundation (architecture) In engineering,

1534-426: Is still quite common and is the easiest of all the piling materials to splice. The normal method for splicing is by driving the leader pile first, driving a steel tube (normally 60–100 cm long, with an internal diameter no smaller than the minimum toe diameter) half its length onto the end of the leader pile. The follower pile is then simply slotted into the other end of the tube and driving continues. The steel tube

1593-409: Is the same as for foundation bearing piles. Contiguous walls are constructed with small gaps between adjacent piles. The spacing of the piles can be varied to provide suitable bending stiffness. Secant pile walls are constructed such that space is left between alternate 'female' piles for the subsequent construction of 'male' piles. Construction of 'male' piles involves boring through the concrete in

1652-624: The Horns Rev wind farm in the North Sea west of Denmark utilizes 80 large monopiles of 4 metres diameter sunk 25 meters deep into the seabed, while the Lynn and Inner Dowsing Wind Farm off the coast of England went online in 2008 with over 100 turbines, each mounted on a 4.7-metre-diameter monopile foundation in ocean depths up to 18 metres. The typical construction process for a wind turbine subsea monopile foundation in sand includes driving

1711-414: The frost line and may have a drain pipe which helps groundwater drain away. They are suitable for soils with a capacity of more than 10 tonnes/m (2,000 pounds per square foot). Often called footings , are usually embedded about a meter or so into soil . One common type is the spread footing which consists of strips or pads of concrete (or other materials) which extend below the frost line and transfer

1770-597: The staith spelling as a distinction from simple wharves: for example, Dunston Staiths in Gateshead and Brancaster Staithe in Norfolk . However, the term staith may also be used to refer only to loading chutes or ramps used for bulk commodities like coal in loading ships and barges. Quay , on the other hand, has its origin in the Proto-Celtic language . Before it changed to its current form under influence of

1829-646: The 'female' piles hole in order to key 'male' piles between. The male pile is the one where steel reinforcement cages are installed, though in some cases the female piles are also reinforced. Secant piled walls can either be true hard/hard, hard/intermediate (firm), or hard/soft, depending on design requirements. Hard refers to structural concrete and firm or soft is usually a weaker grout mix containing bentonite. All types of wall can be constructed as free standing cantilevers , or may be propped if space and sub-structure design permit. Where party wall agreements allow, ground anchors can be used as tie backs. A slurry wall

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1888-752: The Republic of Ireland, and may also refer to neighbourhoods and roadways running along the wayside (for example, Queen's Quay in Toronto and Belfast ). The term wharf is more common in the United States. In some contexts wharf and quay may be used to mean pier , berth , or jetty . In old ports such as London (which once had around 1700 wharves) many old wharves have been converted to residential or office use. Certain early railways in England referred to goods loading points as "wharves". The term

1947-509: The binders and refilling them in the desired area. The technique can also be used on lightly contaminated masses as a means of binding contaminants, as opposed to excavating them and transporting to landfill or processing. As the name implies, timber piles are made of wood . Historically, timber has been a plentiful, locally available resource in many areas. Today, timber piles are still more affordable than concrete or steel. Compared to other types of piles (steel or concrete), and depending on

2006-412: The driven pile, and the sand and water are removed from the centre of the pile and replaced with concrete . An additional layer of even larger stone, up to 0.5 m diameter, is applied to the surface of the seabed for longer-term erosion protection. Also called caissons , drilled shafts , drilled piers , cast-in-drilled-hole piles (CIDH piles) or cast-in-situ piles, a borehole is drilled into

2065-458: The excavation proceeds, horizontal timber sheeting (lagging) is inserted behind the H pile flanges. The horizontal earth pressures are concentrated on the soldier piles because of their relative rigidity compared to the lagging. Soil movement and subsidence is minimized by installing the lagging immediately after excavation to avoid soil loss. Lagging can be constructed by timber, precast concrete, shotcrete and steel plates depending on spacing of

2124-447: The grade beams, while heavier elements bear directly on the pile cap. A monopile foundation utilizes a single, generally large-diameter, foundation structural element to support all the loads (weight, wind, etc.) of a large above-surface structure. A large number of monopile foundations have been utilized in recent years for economically constructing fixed-bottom offshore wind farms in shallow-water subsea locations. For example,

2183-453: The ground in situ ; other deep foundations are typically put in place using excavation and drilling. The naming conventions may vary between engineering disciplines and firms. Deep foundations can be made out of timber , steel , reinforced concrete or prestressed concrete . Prefabricated piles are driven into the ground using a pile driver . Driven piles are constructed of wood, reinforced concrete, or steel. Wooden piles are made from

2242-513: The ground conditions, loading conditions, and nature of the project. Pile depths may vary substantially across a project if the bearing layer is not level. Drilled piles can be tested using a variety of methods to verify the pile integrity during installation. Under-reamed piles have mechanically formed enlarged bases that are as much as 6 m in diameter. The form is that of an inverted cone and can only be formed in stable soils or rocks. The larger base diameter allows greater bearing capacity than

2301-413: The ground is continuously frozen , adfreeze piles are used as the primary structural foundation method. Adfreeze piles derive their strength from the bond of the frozen ground around them to the surface of the pile. Adfreeze pile foundations are particularly sensitive in conditions which cause the permafrost to melt. If a building is constructed improperly then it can melt the ground below, resulting in

2360-432: The ground level, and wood beams bearing on the piers are used to support the structure. This type of foundation results in a crawl space underneath the building in which wiring and duct work can be laid during construction or re-modelling. In jet piling high pressure water is used to set piles. High pressure water cuts through soil with a high-pressure jet flow and allows the pile to be fitted. One advantage of Jet Piling:

2419-438: The ground, then concrete (and often some sort of reinforcing) is placed into the borehole to form the pile. Rotary boring techniques allow larger diameter piles than any other piling method and permit pile construction through particularly dense or hard strata. Construction methods depend on the geology of the site; in particular, whether boring is to be undertaken in 'dry' ground conditions or through water-saturated strata. Casing

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2478-442: The height may be as short as half the diameter. Clays and muds are easy to penetrate but provide poor holding capacity, so the height may be as much as eight times the diameter. The open nature of gravel means that water would flow through the ground during installation, causing 'piping' flow (where water boils up through weaker paths through the soil). Therefore, suction piles cannot be used in gravel seabeds. In high latitudes where

2537-457: The load to the soil and is sized accordingly. Suction piles are used underwater to secure floating platforms. Tubular piles are driven into the seabed (or more commonly dropped a few metres into a soft seabed) and then a pump sucks water out at the top of the tubular, pulling the pile further down. The proportions of the pile (diameter to height) are dependent upon the soil type. Sand is difficult to penetrate but provides good holding capacity, so

2596-695: The modern French quai , its Middle English spelling was key , keye or caye . This in turn also came from the Old Norman cai ( Old French / French chai "wine cellar"), meaning originally "earth bank near a river", then "bank built at a port to allow ship docking". The French term quai comes, through Picard or Norman-French, from Gaulish caio , ultimately tracing back to the Proto-Celtic *kagio- "to encompass, enclose". Modern cognates include Welsh cae "fence, hedge" and Cornish ke "hedge", Deep foundation A deep foundation

2655-545: The motto of the Pile Driving Contractors' Association is "A Driven Pile...Is a Tested Pile!". Foundations relying on driven piles often have groups of piles connected by a pile cap (a large concrete block into which the heads of the piles are embedded) to distribute loads that are greater than one pile can bear. Pile caps and isolated piles are typically connected with grade beams to tie the foundation elements together; lighter structural elements bear on

2714-793: The northeast and east of England the term staith or staithe (from the Norse for landing stage) is also used. The two terms have historically had a geographical distinction: those to the north in the Kingdom of Northumbria used the Old English spelling staith , southern sites of the Danelaw took the Danish spelling staithe . Both originally referred to jetties or wharves. In time, the northern coalfields of Northumbria developed coal staiths specifically for loading coal onto ships and these would adopt

2773-429: The soil to increase bearing capacity. The result is not as solid as concrete, but should be seen as an improvement of the bearing capacity of the original soil. The technique is most often applied on clays or organic soils like peat . The mixing can be carried out by pumping the binder into the soil whilst mixing it with a device normally mounted on an excavator or by excavating the masses, mixing them separately with

2832-421: The soldier piles and the type of soils. Soldier piles are most suitable in conditions where well constructed walls will not result in subsidence such as over-consolidated clays, soils above the water table if they have some cohesion, and free draining soils which can be effectively dewatered, like sands. Unsuitable soils include soft clays and weak running soils that allow large movements such as loose sands. It

2891-446: The source/type of timber, timber piles may not be suitable for heavier loads. A main consideration regarding timber piles is that they should be protected from rotting above groundwater level. Timber will last for a long time below the groundwater level. For timber to rot, two elements are needed: water and oxygen. Below the groundwater level, dissolved oxygen is lacking even though there is ample water. Hence, timber tends to last for

2950-428: The stronger layer of subsoil below. There are different types of deep footings including impact driven piles, drilled shafts, caissons , screw piles , geo-piers and earth-stabilized columns . The naming conventions for different types of footings vary between different engineers. Historically, piles were wood , later steel , reinforced concrete , and pre-tensioned concrete . A type of deep foundation which uses

3009-443: The structure's stability from the ground: The design and the construction of a well-performing foundation must possess some basic requirements: Buildings and structures have a long history of being built with wood in contact with the ground. Post in ground construction may technically have no foundation. Timber pilings were used on soft or wet ground even below stone or masonry walls. In marine construction and bridge building

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3068-439: The top, visible course of stone is hewn, quarried stones. Besides using mortar, stones can also be put in a gabion . One disadvantage is that if using regular steel rebars , the gabion would last much less long than when using mortar (due to rusting). Using weathering steel rebars could reduce this disadvantage somewhat. Rubble trench foundations are a shallow trench filled with rubble or stones. These foundations extend below

3127-423: The trunks of tall trees. Concrete piles are available in square, octagonal, and round cross-sections (like Franki piles ). They are reinforced with rebar and are often prestressed . Steel piles are either pipe piles or some sort of beam section (like an H-pile). Historically, wood piles used splices to join multiple segments end-to-end when the driven depth required was too long for a single pile; today, splicing

3186-486: The type of equipment used to install these elements, they are often used where access restrictions and or very difficult ground conditions (cobbles and boulders, construction debris, karst, environmental sensitivity) exists or to retrofit existing structures.  Occasionally, in difficult ground, they are used for new construction foundation elements. Typical applications include underpinning , bridge , transmission tower and slope stabilization projects. The use of

3245-626: The water jet lubricates the pile and softens the ground. The method is in use in Norway. Micropiles are small diameter, generally less than 300mm diameter, elements that are drilled and grouted in place.  They typically get their capacity from skin friction along the sides of the element, but can be end bearing in hard rock as well. Micropiles are usually heavily reinforced with steel comprising more than 40% of their cross section. They can be used as direct structural support or as ground reinforcement elements.  Due to their relatively high cost and

3304-517: The water. A pier, raised over the water rather than within it, is commonly used for cases where the weight or volume of cargos will be low. Smaller and more modern wharves are sometimes built on flotation devices ( pontoons ) to keep them at the same level as the ship, even during changing tides. In everyday parlance the term quay (pronounced 'key') is common in the United Kingdom, Canada, Australia, and many other Commonwealth countries, and

3363-562: The weight from walls and columns to the soil or bedrock . Another common type of shallow foundation is the slab-on-grade foundation where the weight of the structure is transferred to the soil through a concrete slab placed at the surface. Slab-on-grade foundations can be reinforced mat slabs, which range from 25 cm to several meters thick, depending on the size of the building, or post-tensioned slabs, which are typically at least 20 cm for houses, and thicker for heavier structures. Another way to install ready-to-build foundations that

3422-717: Was carried over from marine usage. The person who was resident in charge of the wharf was referred to as a "wharfinger". The word wharf comes from the Old English hwearf , cognate to the Old Dutch word werf , which both evolved to mean "yard", an outdoor place where work is done, like a shipyard ( Dutch : scheepswerf ) or a lumberyard (Dutch: houtwerf ). Originally, werf or werva in Old Dutch ( werf , wer in Old Frisian ) simply referred to inhabited ground that

3481-460: Was not yet built on (similar to " yard " in modern English), or alternatively to a terp . This could explain the name Ministry Wharf located at Saunderton, just outside High Wycombe, which is nowhere near any body of water. In support of this explanation is the fact that many places in England with "wharf" in their names are in areas with a high Dutch influence, for example the Norfolk broads. In

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