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In the construction industry, moling is a trenchless method used to lay pipes. During the moling process, a pneumatically-driven machine known as a mole forces its way through the soil along the desired path of the pipe. Moling avoids the need to dig a trench and can be used to lay water pipes and the heating coils of heat pump systems. [1]
Recently moles that are steerable have been developed allowing an operator to correct the track of the mole and to achieve curved bores.
The standard approach to moling is to dig a hole about 1 m square and 2 m deep. Such a hole is small enough that it can be dug by hand instead of by machine in inaccessible locations. The mole is then entered into the earth on the horizontal face at the bottom of this hole. A destination hole of similar proportions is also dug, and this is where the mole emerges. The mole itself is a steel cylinder about 60 cm long and 6 cm in diameter. It works as a pneumatic cylinder with pulsed compressed air causing the head of the mole to repeatedly hammer against the soil in front of the mole. Once the mole has passed through the earth the pipe can be pulled through the long horizontal hole.
A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. Tunnels are excavated through hard rock, wet or dry soil, or sand, each of which requires specialized technology.
Trenchless technology is a type of subsurface construction work that requires few trenches or no continuous trenches. It is a rapidly growing sector of the construction and civil engineering industry. It can be defined as "a family of methods, materials, and equipment capable of being used for the installation of new or replacement or rehabilitation of existing underground infrastructure with minimal disruption to surface traffic, business, and other activities."
A drilling rig is an integrated system that drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the earth's subsurface. Drilling rigs can be massive structures housing equipment used to drill water wells, oil wells, or natural gas extraction wells, or they can be small enough to be moved manually by one person and such are called augers. Drilling rigs can sample subsurface mineral deposits, test rock, soil and groundwater physical properties, and also can be used to install sub-surface fabrications, such as underground utilities, instrumentation, tunnels or wells. Drilling rigs can be mobile equipment mounted on trucks, tracks or trailers, or more permanent land or marine-based structures. The term "rig" therefore generally refers to the complex equipment that is used to penetrate the surface of the Earth's crust.
The American shrew mole is the smallest species of mole. It is the only living member of the genus Neurotrichus and the tribe Neurotrichini. It is also known as Gibb's shrew mole and least shrew mole. It is not closely related to the Asian shrew mole. The reason that it is called a "shrew mole" instead of being called either a "shrew" or a "mole" is because of its fur, which is a characteristic of shrews and its large head and heavy dentition, which is characteristic of moles.
Tracker action is a term used in reference to pipe organs and steam calliopes to indicate a mechanical linkage between keys or pedals pressed by the organist and the valve that allows air to flow into pipe(s) of the corresponding note. This is in contrast to "direct electric action" and "electro-pneumatic action", which connect the key to the valve through an electrical link or an electrically assisted pneumatic system respectively, or "tubular-pneumatic action" which utilizes a change of pressure within lead tubing which connects the key to the valve pneumatic.
Pipe bursting is a trenchless method of replacing buried pipelines without the need for a traditional construction trench. "Launching and receiving pits" replace the trench needed by conventional pipe-laying.
Directional boring, also referred to as horizontal directional drilling (HDD), is a minimal impact trenchless method of installing underground utilities such as pipe, conduit, or cables in a relatively shallow arc or radius along a prescribed underground path using a surface-launched drilling rig. Directional boring offers significant environmental advantages over traditional cut and cover pipeline/utility installations. The technique is routinely used when conventional trenching or excavating is not practical or when minimal surface disturbance is required.
A cured-in-place pipe (CIPP) is a trenchless rehabilitation method used to repair existing pipelines. It is a jointless, seamless pipe lining within an existing pipe. As one of the most widely used rehabilitation methods, CIPP has applications in sewer, water, gas, chemical and district heating pipelines ranging in diameter from 0.1 to 2.8 meters.
Pipe ramming is a trenchless method for installation of steel pipes and casings. Distances of 30 m or more and over 500 mm in diameter are common, although the method can be used for much longer and larger installations. The method is useful for pipe and casing installations under railway lines and roads, where other trenchless methods could cause subsidence or heaving. The majority of installations are horizontal, although the method can be used for vertical installations.
Landslide mitigation refers to several human-made activities on slopes with the goal of lessening the effect of landslides. Landslides can be triggered by many, sometimes concomitant causes. In addition to shallow erosion or reduction of shear strength caused by seasonal rainfall, landslides may be triggered by anthropic activities, such as adding excessive weight above the slope, digging at mid-slope or at the foot of the slope. Often, individual phenomena join to generate instability over time, which often does not allow a reconstruction of the evolution of a particular landslide. Therefore, landslide hazard mitigation measures are not generally classified according to the phenomenon that might cause a landslide. Instead, they are classified by the sort of slope stabilization method used:
A subsoiler or flat lifter is a tractor-mounted farm implement used for deep tillage, loosening and breaking up soil at depths below the levels worked by moldboard ploughs, disc harrows, or rototillers. Most such tools will break up and turn over surface soil to a depth of 15–20 cm (6–8 in), whereas a subsoiler will break up and loosen soil to twice those depths.
A well is an excavation or structure created in the earth by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. The well water is drawn up by a pump, or using containers, such as buckets or large water bags that are raised mechanically or by hand. Water can also be injected back into the aquifer through the well. Wells were first constructed at least eight thousand years ago and historically vary in construction from a simple scoop in the sediment of a dry watercourse to the qanats of Iran, and the stepwells and sakiehs of India. Placing a lining in the well shaft helps create stability, and linings of wood or wickerwork date back at least as far as the Iron Age.
Soil steam sterilization is a farming technique that sterilizes soil with steam in open fields or greenhouses. Pests of plant cultures such as weeds, bacteria, fungi and viruses are killed through induced hot steam which causes vital cellular proteins to unfold. Biologically, the method is considered a partial disinfection. Important heat-resistant, spore-forming bacteria can survive and revitalize the soil after cooling down. Soil fatigue can be cured through the release of nutritive substances blocked within the soil. Steaming leads to a better starting position, quicker growth and strengthened resistance against plant disease and pests. Today, the application of hot steam is considered the best and most effective way to disinfect sick soil, potting soil and compost. It is being used as an alternative to bromomethane, whose production and use was curtailed by the Montreal Protocol. "Steam effectively kills pathogens by heating the soil to levels that cause protein coagulation or enzyme inactivation."
A direct exchange (DX) geothermal heat pump is a type of ground source heat pump in which refrigerant circulates through copper tubing placed in the ground unlike other ground source heat pumps where refrigerant is restricted to the heat pump itself with a secondary loop in the ground filled with a mixture of water and anti-freeze.
An agricultural drainage system is a system by which water is drained on or in the soil to enhance agricultural production of crops. It may involve any combination of stormwater control, erosion control, and watertable control.
The purpose of a land drain is to allow water in wet or swampy ground to rapidly drain away or to relieve hydrostatic pressure. They are subterranean linear structures which are laid to a fall which should be as steep as practicable. They are used in agriculture and in building construction sites. Modern land drains take the form of a perforated or discontinuous pipe. Typically, the land drains conduct the surplus water to an open ditch or natural water source.
Underground pneumatic boring is a trenchless method of installing underground utilities.
Suranga is a traditional water management system used to provide a reliable supply of water for human settlements and irrigation in Kasargod district of Kerala and Dakshin Kannada district of Karnataka, India. A suranga is basically a horizontal tunnel dug in the slope of a laterite hill for about 30 metres (98 ft) to 40 metres (130 ft), which uses gravitational force for extraction of the underground water and collect into a storage tank. As both the areas are covered by uneven and steep laterite hill which makes boring of traditional bore well hard and expensive, surangas are considered as a relatively cheap option.
A pipelayer is a skilled tradesman who lays pipe, such as for storm sewers, sanitary sewers, drains, and water mains. Pipelayers may grade trenches and culverts, position pipe, or seal joints. The Standard Occupational Classification System code for pipelayers is 47-2151.
An earth auger, earth drill, or post-hole auger is a drilling tool used for making holes in the ground. It typically consists of a rotating vertical metal rod or pipe with one or more blades attached at the lower end, that cut or scrape the soil.