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 Cliff stabilization is a coastal management erosion control technique. This is most suitable for softer or less stable cliffs. Generally speaking, the cliffs are stabilised through dewatering (drainage of excess rainwater to reduce water-logging) or ...
* Grout curtain
* Retaining wall
* Slurry wall
* Soil nailing
* Tieback (geotechnical)
* Trench shoring
* Caisson
* Dam
* Gabion
* Ground freezing
Gallery
Excavation
Excavation may be classified by type of material:Frederick S. Merritt, M. Kent Loftin, Jonathan T. Ricketts, ''Standard Handbook for Civil Engineers, Fourth Edition'', McGraw-Hill Book Company, 1995.
* Topsoil excavation
* Earth excavation
* Rock excavation
* Muck excavation – this usually contains excess water and unsuitable soil
* Unclassified excavation – this is any combination of material types
Excavation may be classified by the purpose:
* Stripping
* Roadway excavation
* Drainage or structure excavation
* Bridge excavation
* Channel excavation
* Footing excavation
* Borrow excavation
* Dredge excavation
* Underground excavation
Civil engineering use
Typical earthworks include road construction, railway beds,causeways
A causeway is a track, road or railway on the upper point of an embankment across "a low, or wet place, or piece of water". It can be constructed of earth, masonry, wood, or concrete. One of the earliest known wooden causeways is the Sweet ...
, dams, levee
A levee (), dike (American English), dyke (English in the Commonwealth of Nations, Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually soil, earthen and that often runs parallel (geometry), parallel to ...
s, canals, and berms. Other common earthworks are land grading to reconfigure the topography of a site, or to stabilize slopes.
Military use
In military engineering, earthworks are, more specifically, types of fortifications constructed from soil. Although soil is not very strong, it is cheap enough that huge quantities can be used, generating formidable structures. Examples of older earthwork fortifications include moat
A moat is a deep, broad ditch, either dry or filled with water, that is dug and surrounds a castle, fortification, building or town, historically to provide it with a preliminary line of defence. In some places moats evolved into more extensive ...
s, sod walls, motte-and-bailey
A motte-and-bailey castle is a European fortification with a wooden or stone keep situated on a raised area of ground called a motte, accompanied by a walled courtyard, or bailey, surrounded by a protective ditch and palisade. Relatively easy to ...
castles, and hill forts. Modern examples include trenches and berms.
Equipment
Heavy construction equipment is usually used due to the amounts of material to be moved — up to millions of cubic metres. Earthwork construction was revolutionized by the development of the ( Fresno)scraper
Scrape, scraper or scraping may refer to:
Biology and medicine
* Abrasion (medical), a type of injury
* Scraper (biology), grazer-scraper, a water animal that feeds on stones and other substrates by grazing algae, microorganism and other matter ...
and other earth-moving machines such as the loader, the dump truck, the grader, the bulldozer
A bulldozer or dozer (also called a crawler) is a large, motorized machine equipped with a metal blade to the front for pushing material: soil, sand, snow, rubble, or rock during construction work. It travels most commonly on continuous track ...
, the backhoe
A backhoe—also called rear actor or back actor—is a type of excavating equipment, or digger, consisting of a digging bucket on the end of a two-part articulated arm. It is typically mounted on the back of a tractor or front loader, the latt ...
, and the dragline excavator.
Mass haul planning
Engineers need to concern themselves with issues of geotechnical engineering
Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. It uses the principles of soil mechanics and rock mechanics for the solution of its respective engineering problems. It als ...
(such as soil density and strength) and with quantity estimation to ensure that soil volumes in the cuts match those of the fills, while minimizing the distance of movement. In the past, these calculations were done by hand using a slide rule and with methods such as Simpson's rule. Earthworks cost is a function of hauled amount x hauled distance. The goal of mass haul planning is to determine these amounts and the goal of mass haul optimization is to minimize either or both.
Now they can be performed with a computer
A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...
and specialized software, including optimisation on haul cost and not haul distance (as haul cost is not proportional to haul distance).
See also
* * *, construction/engineering vehicles used for earthworks civil engineering * * * * * * * *Calculation software
The table below provides a list of software used in the engineering and construction industries to plan, execute and cost these earthworks.
Earthwork software is generally a subset of CAD software, in which case it often an add-on to a more general CAD package such as AutoCAD. In that case, earthwork software is principally used to calculate cut and fill volumes which are then used for producing material and time estimates. Most products offer additional functionality such as the ability to takeoff terrain elevation from plans (using contour lines and spot heights); produce shaded cut and fill maps; produce cross sections and visualize terrain in 3D. The means by which volumes are calculated in software can differ quite considerably leading to potentially different results with the same input data. Many software products use methods based on triangulated irregular networks (TINS) and triangular prism volume algorithms, however other calculation methods are in use based on rationalizing elevations into high density grids or cross-sections.
A few programs are specialised in earthworks transport optimization and planning the construction works.
References
External links
*Finding Volume of Earthwork using Simpson's Rule
{{Geotechnical engineering Fortification (architectural elements) Civil engineering