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Section through railway track and foundation showing the sub-grade. Grading in civil engineering and landscape architectural construction is the work of ensuring a level base, or one with a specified slope, [1] for a construction work such as a foundation, the base course for a road or a railway, or landscape and garden improvements, or surface drainage.
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 moats, sod walls, motte-and-bailey castles, and hill forts.
Technical Specification, Edition 1.0, September 2023 [3] IEC 62443-2-1 Security program requirements for IACS asset owners Edition 2.0, 2024 [4] This part of the standard is aimed at operators of automation solutions and defines requirements for how security during the operation of plants is to be considered (see ISO/IEC 27001). IEC 62443-2-3
Turning is a term used when referring to moving the level to take an elevation shot from a different location. To "turn" the level, one must first take a reading and record the elevation of the point the rod is located on. While the rod is being kept in exactly the same location, the level is moved to a new location where the rod is still visible.
The metric rod has major numbered graduations in meters and tenths of meters (e.g. 18 is 1.8 m - there is a tiny decimal point between the numbers). Between the major marks are either a pattern of squares and spaces in different colours or an E shape (or its mirror image) with horizontal components and spaces between of equal size. In both ...
The commonly used datum is mean sea level. [3] Dumpy level – optical instrument used to establish or check points in the same horizontal plane. It is used in surveying and building with a vertical staff to measure height differences and to transfer, measure and set heights. Also called a builder's level or leveling instrument.
As a general guide for Zone 2, unwanted substances should only be present under 10 hours per year or 0–0.1% of the time. [3] Unclassified locations Also known as non-hazardous or ordinary locations, these locations are determined to be neither Class I, Division 1 or Division 2; Zone 0, Zone 1 or Zone 2; or any combination thereof.
The E horizon (or Ae in Canadian soil classification system), which is usually 4 to 8 centimetres (1.6 to 3.1 in) thick, is low in Fe and Al oxides and humus. It is formed under moist, cool and acidic conditions, especially where the parent material, such as granite or sandstone , is rich in quartz .