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Pipe Ramming
Pipe ramming (sometimes also called pipe jacking) is a trenchless method for installation of steel pipes and casings. Distances of 30 m (150 feet) or more and over 500 mm (20 inches) 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. The main differences between pipe ramming and pipe jacking are that pipe ramming uses percussion and does not have a navigation system, while pipe jacking uses hydraulic jacks and does have an active navigation system. Pipe ramming is preferable for shorter distances and applications that do not require tight directional control, such as cable installations. The method uses pneumatic percussive blows to drive the pipe through the ground. The leadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trenchless
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." Trenchless & construction Trenchless construction includes such construction methods as tunneling, microtunneling (MTM), horizontal directional drilling (HDD) also known as directional boring, pipe ramming (PR), pipe jacking (PJ), moling, horizontal auger boring (HAB) and other methods for the installation of pipelines and cables below the ground with minimal excavation. Large diameter tunnels such as those constructed by a tunnel boring machine (TBM), and drilling and blasting techniques are larger versions of subsurface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel Pipe
A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases (fluids), slurries, powders and masses of small solids. It can also be used for structural applications; hollow pipe is far stiffer per unit weight than solid members. In common usage the words ''pipe'' and ''tube'' are usually interchangeable, but in industry and engineering, the terms are uniquely defined. Depending on the applicable standard to which it is manufactured, pipe is generally specified by a nominal diameter with a constant outside diameter (OD) and a schedule that defines the thickness. Tube is most often specified by the OD and wall thickness, but may be specified by any two of OD, inside diameter (ID), and wall thickness. Pipe is generally manufactured to one of several international and national industrial standards. While similar standards exist for specific industry applicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipeline Transport
Pipeline transport is the long-distance transportation of a liquid or gas through a system of pipes—a pipeline—typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than of pipeline in 120 countries of the world. The United States had 65%, Russia had 8%, and Canada had 3%, thus 76% of all pipeline were in these three countries. ''Pipeline and Gas Journals worldwide survey figures indicate that of pipelines are planned and under construction. Of these, represent projects in the planning and design phase; reflect pipelines in various stages of construction. Liquids and gases are transported in pipelines, and any chemically stable substance can be sent through a pipeline. Pipelines exist for the transport of crude and refined petroleum, fuels – such as oil, natural gas and biofuels – and other fluids including sewage, slurry, water, beer, hot water or steam for shorter distances. Pipelines are useful for transporting water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Line
Rail terminology is a form of technical terminology. The difference between the American term ''railroad'' and the international term ''railway'' (used by the International Union of Railways and English-speaking countries outside the United States) is the most significant difference in rail terminology. These and other terms have often originated from the parallel development of rail transport systems in different parts of the world. In English-speaking countries outside the United Kingdom, a mixture of US and UK terms may exist. Various global terms are presented here. Where a term has multiple names, this is indicated. The abbreviation "UIC" refers to standard terms adopted by the International Union of Railways in its official publications and thesaurus. 0–9 A B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Road
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation. There are many types of roads, including parkways, avenues, controlled-access highways (freeways, motorways, and expressways), tollways, interstates, highways, thoroughfares, and local roads. The primary features of roads include lanes, sidewalks (pavement), roadways (carriageways), medians, shoulders, verges, bike paths (cycle paths), and shared-use paths. Definitions Historically many roads were simply recognizable routes without any formal construction or some maintenance. The Organization for Economic Co-operation and Development (OECD) defines a road as "a line of communication (travelled way) using a stabilized base other than rails or air strips open to public traffic, primarily for the use of road motor vehicles running on their own wheels", whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subsidence
Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement. Processes that lead to subsidence include dissolution of underlying carbonate rock by groundwater; gradual compaction of sediments; withdrawal of fluid lava from beneath a solidified crust of rock; mining; pumping of subsurface fluids, such as groundwater or petroleum; or warping of the Earth's crust by tectonic forces. Subsidence resulting from tectonic deformation of the crust is known as tectonic subsidence and can create accommodation for sediments to accumulate and eventually lithify into sedimentary rock. Ground subsidence is of global concern to geologists, geotechnical engineers, surveyors, engineers, urban planners, landowners, and the public in general.National Research Council, 1991. ''Mitigating losses from land subsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Compaction
In geotechnical engineering, soil compaction is the process in which stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water (or other liquid) being displaced from between the soil grains, then consolidation, not compaction, has occurred. Normally, compaction is the result of heavy machinery compressing the soil, but it can also occur due to the passage of, for example, animal feet. In soil science and agronomy, soil compaction is usually a combination of both engineering compaction and consolidation, so may occur due to a lack of water in the soil, the applied stress being internal suction due to water evaporation as well as due to passage of animal feet. Affected soils become less able to absorb rainfall, thus increasing runoff and erosion. Plants have difficulty in compacted soil because the mineral grains are pressed together, leaving little space for air and wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentonite
Bentonite () is an absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelling capacity than Ca-montmorillonite. Bentonite usually forms from the weathering of volcanic ash in seawater, or by hydrothermal circulation through the porosity of volcanic ash beds, which converts (devitrification) the volcanic glass ( obsidian, rhyolite, dacite) present in the ash into clay minerals. In the mineral alteration process, a large fraction (up to 40-50 wt.%) of amorphous silica is dissolved and leached away, leaving the bentonite deposit in place. Bentonite beds are white or pale blue or green (traces of reduced ) in fresh exposures, turning to a cream color and then yellow, red, or brown (traces of oxidized ) as the exposure is weathered further. As a swelling clay, bentonite has the ability to absorb large quantities of water, which increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymers
A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Boring
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. Although often used interchangeably, the terms directional boring and horizontal directional drilling are distinct in that they convey a different sense of scale. The term "directional boring" or "bore" is generally reserved for mini/small sized drilling rigs, small diameter bores, and crossing lengths in terms of hundreds of feet. Generally, the term Horizontal Directional Drilling (HDD) is intended to describe large/maxi si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthworks (engineering)
Earthworks are engineering works created through the processing of parts of the earth's surface involving quantities of soil or unformed rock. Shoring structures An incomplete list of possible temporary or permanent geotechnical shoring structures that may be designed and utilised as part of earthworks: *Mechanically stabilized earth *Earth anchor * Cliff stabilization *Grout curtain *Retaining wall *Slurry wall *Soil nailing *Tieback (geotechnical) *Trench shoring * Caisson *Dam *Gabion *Ground freezing Gallery File:Mechanically stabilized earth diagram.gif, Mechanically stabilized earth File:GroutCurtain.gif, Grout curtain File:Retaining Wall Type Function.jpg, Retaining wall types File:Soil Nail.jpg, Soil nailing File:FEMA - 6044 - Photograph by Larry Lerner taken on 03-15-2002 in New York.jpg, Tieback File:Sbh s600.JPG, Trench shoring File:Caisson Schematic.svg, Caisson File:Vyrnwy dam.JPG, Dam File:Gabion 040.jpg, Gabions File:Cross section of a ground freezing pipe as u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slurry Pipe Jacking Micro Tunneling
A slurry is a mixture of denser solids suspended in liquid, usually water. The most common use of slurry is as a means of transporting solids or separating minerals, the liquid being a carrier that is pumped on a device such as a centrifugal pump. The size of solid particles may vary from 1 micrometre up to hundreds of millimetres. The particles may settle below a certain transport velocity and the mixture can behave like a Newtonian or non-Newtonian fluid. Depending on the mixture, the slurry may be abrasive and/or corrosive. Examples Examples of slurries include: *Cement slurry, a mixture of cement, water, and assorted dry and liquid additives used in the petroleum and other industries *Soil/cement slurry, also called Controlled Low-Strength Material (CLSM), flowable fill, controlled density fill, flowable mortar, plastic soil-cement, K-Krete, and other names *A mixture of thickening agent, oxidizers, and water used to form a gel explosive *A mixture of pyroclastic material, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
