Glossary for the subject CIE5308C

amplitude amplitude (1) The magnitude of the displacement of a wave from a mean value. An ocean wave has an amplitude equal to the vertical distance from still-water level to wave crest. For a sinusoidal wave, the amplitude is one-half the wave height. (2) The semirange of a constituent tide.
Barrier Stuw The function of a barrier is to control the water level. It consists of a combination of a concrete or a steel structure with or without adjacent ROCKFILL DAMS.
Bathymetry diepteligging, bodemprofiel The measurement of depths of water in oceans, seas, and lakes; also information derived from such measurements.
Bed protection bodembescherming A (rock) structure on the sea bed or on the bed of a river or estuary in order to protect the underlying bed against erosion due to current and/or wave action.
boulder clay keileem clay type formed in the ice age, including rocks from moraines; very resistant against erosion.
Boundary condition randvoorwaarde
Buoyancy Opdrijving The resultant of upward forces, exerted by the water on a submerged or floating body, equal to the weight of the water displaced by this body.
Caisson Caisson Concrete box-type structure
Channel geul, kanaal, zeestraat (1) A natural or artificial waterway of perceptible extent which either periodically or continuously contains moving water, or which forms a connecting link between two bodies of water. (2) The part of a body of water deep enough to be used for navigation through an area otherwise too shallow for navigation. (3) A large strait, as the English Channel. (4) The deepest part of a stream, bay, or strait through which the main volume or current of water flows.
Chart datum Referentiepeil The plane or level to which soundings (or elevations) or tide heights are referenced (usually LOW WATER DATUM). The surface is called a tidal datum when referred to a certain phase of tide. To provide a safety factor for navigation, some level lower than MEAN SEA LEVEL is generally selected for hydrographic charts, such as MEAN LOW WATER or MEAN LOWER LOW WATER. See DATUM PLANE.
Clay Klei See SOIL CLASSIFICATION.
cofferdam kistdam A temporary watertight structure enclosing all or part of the construction area so that construction can proceed in the dry.
cohesive cohesief Soil material consisting of fine particles which are in some way bonded (in contradiction to loose sand) like clay
contour dieptelijnen A line on a map or chart representing points of equal elevation with relation to a DATUM. It is called an ISOBATH when connecting points of equal depth below a datum. Also called DEPTH CONTOUR.
crest kruin top part of a construction
Crown kruin Top of a structure
Current Stroom, stroming A flow of water Coastal Current: One of the offshore currents flowing generally parallel to the shoreline in the deeper water beyond and near the surf zone. These are not genetically related to waves and the resulting surf, but may be related to tides, winds, or distribution of mass. >>Ebb current: The tidal current away from shore or down a tidal stream. Usually associated with the decrease in the height of the tide. >>Flood current: The tidal current toward shore or up a tidal stream. Usually associated with the increase in the height of the tide. >>Littoral current: Any current in the littoral zone caused primarily by wave action; e.g., LONGSHORE CURRENT, RIP CURRENT. See also CURRENT, NEARSHORE. >>Longshore current:The littoral current in the breaker zone moving essentially parallel to the shore that is usually generated by waves breaking at an angle to the shoreline. >>Tidal current: The alternating horizontal movement of water associated with the rise and fall of the tide caused by the astronomical tide-producing forces.
Dam Dam Structure built in rivers or estuaries, basically to separate water at both sides and/or to retain water at one side. See also BARRAGE.
Datum Referentievlak See also CHART DATUM.Datum plane is the horizontal plane to which soundings, ground elevations, or water surface elevations are referred. Also reference plane. The plane is called a tidal datum when defined by a certain phase of the tide. The following datums are ordinarily used on hydrographic charts: >>MEAN LOW WATER--Atlantic coast (US), Argentina, Sweden, and Norway >>MEAN LOWER LOW WATER--Pacific coast (US) >>MEAN LOW WATER SPRINGS--United Kingdom) Germany, Italy, Brazil, and Chile. >>LOW WATER DATUM--Great Lakes (U. S. and Canada). >>LOWEST LOW WATER SPRINGS--Portugal. >>LOW WATER INDIAN SPRINGS--India and Japan (See INDIAN TIDE PLANE). LOWEST LOW WATER--France, Spain, and Greece. >>A common datum used on topographic maps is based on MEAN SEA LEVEL. See also BENCHMARK.
Deep water diep water Water so deep that surface waves are little affected by the ocean bottom. Generally, water deeper than one-half the surface wavelength is considered deep water. Compare SHALLOW WATER.
Depth diepte The vertical distance from a specified tidal datum to the sea floor. See also DEEP WATER and SHALLOW WATER
design water level ontwerpwaterstand water level used in the design, usually a waterlevel with a given return probability
dike (dyke) dijk A long, low embankment with a height usually less than four to five metres and a length more than ten or fifteen times the maximum height. Usually applied to protect land from flooding. (Dike is to be preferred above Dyke)
Discharge debiet amount of water flowing trough a cross section per unit of time (m3/s)
Diurnal enkeldaags Having a period or cycle of approximately one tidal day. A diurnal tide is a tide with one high water and one low water in a tidal day.
Ebb eb - vallend water Ebb current: The tidal current away from shore or down a tidal stream and usually associated with the decrease in height of the tide. Ebb tide:The period of tide between high water and the succeeding low water; a falling tide.
Echo sounder echolood An electronic instrument used to determine the depth of water by measuring the time interval between the emission of a sonic or ultrasonic signal and the return of its echo from the bottom.
Embankment dijk, kade An artificial bank such as a mound or dike generally built to retain (hold back) water or to carry a roadway. An embankment is generally higher than a DIKE.
Erosion erosie The wearing away of land by the action of natural forces. On a beach, the carrying away of beach material by wave action, tidal currents, littoral currents, or by deflation.
Estuary zeearm
fascine mattress zinkstuk bedprotection made of brushwood and geotextile to prevent erosion of the subsoil due to currents and waves
Filter Filter Intermediate layer, preventing fine materials of an underlayer from being washed through the voids of an upper layer.
Geotextile Geotextiel A synthetic fabric which may be woven or non-woven used as a FILTER or separation layer.
Gradient Gradient, verhang See SLOPE. With reference to winds or currents, the rate of increase or decrease in speed, usually in the vertical; or the curve that represents this rate.
gradient verhang change in value over a length difference. Height difference divided by distance in height gradient
Gradings Gradering Distribution, with regard to size or weight, of individual stones within a bulk volume. Heavy, light and fine gradings are distinguished.
gradual closure geleidelijke sluiting Method in which the final gap is closed gradually either by the VERTICAL or the HORIZONTAL CLOSURE method or a combination of both methods. This method includes the use of large, massive CAISSONS to be placed on a SILL.
Granular filter Granulair filter A band of granular material which is incorporated in an EMBANKMENT dam and is graded so as to allow SEEPAGE to flow across or down the filter zone without causing the migration of the material from zones adjacent to the FILTER.
Gravel Grind - kiezel See SOIL CLASSIFICATION.
HHW HHW HIGHER HIGH TIDE: The higher of the two high waters of any tidal day. The single high water occurring daily during periods when the tide is diurnal is considered to be a higher high water.
High Hoog see HIGH WATER LINE, HW, HHW, HLW
HLW HLW HIGHER LOW TIDE: The higher of two low waters of any tidal day.
HW Hoog water (HW) HIGH WATER: The maximum elevation reached by each rising tide. See TIDE.
incipient motion begin van beweging The moment sand or stones start to move under flow conditons
Inundation overstroming (inundatie) Inundation is both the act of intentionally flooding land that would otherwise remain dry, for military, agricultural, or river-management purposes, and the result of such an act.
Levee dijk A dike or embankment to protect land from inundation (typical US term,usually along a river, but in New Orleans area also seadikes).
LHW LHW Lower high water: The lower of the two high waters of any tidal day.
liquefaction zettingsvloeiing saturated sand behaving like a fluid
LLW LLW Lower low water: The lower of the two low waters of any tidal day. The single low water occurring daily during periods when the tide is diurnal is considered to be a lower low water.
LW LW Low water: The minimum elevation reached by each falling tide. See TIDE.
mattress, fascine mattress zinkstuk bedprotection made of brushwood and geotextile to prevent erosion of the subsoil due to currents and waves
Mean Tide level A plane midway between MEAN HIGH WATER and MEAN LOW WATER. This is not necessarily equal to MEAN SEA LEVEL. Also HALF-TIDE LEVEL.
Median diameter Mediane diameter The diameter which marks the division of a given sand sample into two equal parts by weight, one part containing all grains larger than that diameter and the other part containing all grains smaller.
MHHW GHHW Mean Higher High Water: The average height of the higher high waters over a 19-year period. For shorter periods of observation, corrections are applied to eliminate known variations and reduce the result to the equivalent of a mean 19-year value.
MHW GHW Mean High Water: The average height of the high waters over a 19-year period. For shorter periods of observations, corrections are applied to eliminate known variations and reduce the results to the equivalent of a mean 19-year value. All high water heights are included in the average where the type of tide is either semidiurnal or mixed. Only the higher high water heights are included in the average where the type of tide is diurnal. So determined, mean high water in the latter case is the same as mean higher high water.
MHWS GHWS Mean High Water Spring: The average height of the high waters occurring at the time of spring tide. Frequently abbreviated to HIGH WATER SPRINGS.
Mixed tide gemengd getij A type of tide in which the presence of a diurnal wave is conspicuous by a large inequality in either the high or low water heights, with two high waters and two low waters usually occurring each tidal day. In strictness, all tides are mixed, but the name is usually applied without definite limits to the tide intermediate to those predominantly semidiurnal and those predominantly diurnal
MLLW GLLW Mean Lower Low Water: The average height of the lower low-waters, over a 19-year period. For shorter periods of observations, corrections are applied to eliminate known variations and reduce the results to the equivalent of a mean 19-year value. Frequently abbreviated to LOWER LOW WATER.
MLW GLW Mean Low Water: The average height of the low waters over a 19-year period. For shorter periods of observations, corrections are applied to eliminate known variations and reduce the results to the equivalent of a mean 19-year value. All low water heights are included in the average where the type of tide is either semidiurnal or mixed. Only lower low water heights are included in the average where the type of tide is diurnal. So determined, mean low water in the latter case is the same as mean lower low water.
MLWS GLWS Mean Low Water Spring: The average height of low waters occurring at the time of the spring tides. It is usually derived by taking a plane depressed below the half-tide level by an amount equal to one-half the spring range of tide, necessary corrections being applied to reduce the result to a mean value. This plane is used to a considerable extent for hydrographic work outside of the United States and is the plane of reference for the Pacific approaches to the Panama Canal. Frequently abbreviated to LOW WATER SPRINGS.
MWL NAP Mean Water Level or Mean Sea Level: The average height of the surface of the sea for all stages of the tide over a 19-year period. This is usually determined from hourly height readings and is not necessarily equal to MEAN TIDE LEVEL.
neap tide dood tij A tide occurring near the time of quadrature of the moon with the sun. The neap tidal range is usually 10 to 30 percent less than the mean tidal range.
Overflow overloop
Permeability Doorlatendheid
permeable doorlatend construction where water may flow through; usually with small openings to prevent passing of sand
Prototype Prototype In laboratory usage, the full-scale structure, concept, or phenomenon used as a basis for constructing a scale model or copy.
quarry steengroeve an excavation or pit from which building stone is obtained by cutting, blasting, etc.
quarry stone breuksteen Any stone processed from a quarry.
quicksand drijfzand Loose, yielding, wet sand which offers no support to heavy objects. The upward flow of the water has a velocity that eliminates contact pressures between the sand grains and causes the sand-water mass to behave like a fluid.
riprap breuksteen, stortsteen A protective layer or facing of quarrystone, usually well graded within wide size limit, randomly placed to prevent erosion, scour, or sloughing of an embankment of bluff; also the stone so used. The quarrystone is placed in a layer that is at least twice the thickness of the 50 percent size or 1.25 times the thickness of the largest size stone in the gradation.
Rubble breuksteen, puin, stortsteen (1) Loose angular water worn stones along a beach. (2) Rough, irregular fragments of broken rock. See also RUBBLE MOUND
saltmarsh kwelder An area periodically flooded by water, usually above normal high water
scour ontgronding, uitschuring Removal of underwater material by waves and currents, especially at the base or toe of a shore structure.
Seepage kwel
Semidiurnal tide dubbeldaags getij A tide with two high waters and two low waters in a tidal day with comparatively little diurnal inequality.
sheet pile damwand
sill drempel Shallow area in a gap, usually created as a foundation for a dam or an other structure
slack water kentering The state of a tidal current when its velocity is near zero, especially the moment when a reversing current changes direction and its velocity is zero. Sometimes considered the intermediate period between ebb and flood currents during which the velocity of the currents is less than 0.05 meter per second (0.1 knot).
sluice caisson doorlaatcaisson concrete caisson including weirs for closing works, these caissons prevent flow contraction during closing operation
Sounding dieptemeting A measured depth of water. On hydrographic charts, the soundings are adjusted to a specific plane of reference, the sounding datum. See also SOUNDING LINE
split-barge splijtbak
spur (-dike), wingdam (USA) krib, scherm, hoofd
storm surge stormvloed A rise above normal water level on the open coast due to the action of wind stress on the water surface. Storm surge resulting from a hurricane also includes that rise in level due to atmospheric pressure reduction as well as that due to wind stress. See WIND SETUP.
submerged weir, imperfect weir, submerged overfall onvolkomen overlaat
surge deinen The name applied to wave motion with a period intermediate between that of the ordinary wind wave and that of the tide, say from 1/2 to 60 minutes. It is low in height, usually less than 0.9 meter (0.3 foot). See also SEICHE.
surge stormopzet
SWL stil water niveau Still Water level, the elevation that the surface of the water would assume if all wave action were absent.
tidal flat closure maaiveldsluiting closing a tidal entrance by closing the shallow parts on the tidal flats
tidal gully closure, tidal closure stroomgat sluiting closing a tidal entrance by closing the gully as last closing part
tidal prism komberging The total amount of water that flows into a harbour or estuary or out again with movement of the tide, excluding any freshwater flow.
Tidal range Tijverschil The difference in height between consecutive high and low (or higher high and lower low) waters.
Tidal wave Getijgolf (1) The wave motion of the tides. (2) In popular usage, any unusually high and destructive water level along a shore. It usually refers to STORM SURGE (or sometimes erroneously to TSUNAMI).
Tide getijprisma The periodic rising and falling of the water that results from gravitational attraction of the Moon and Sun and other astronomical bodies acting upon the rotating Earth. Although the accompanying horizontal movement of the water resulting from the same cause is also sometimes called the tide, it is preferable to designate the latter as TIDAL CURRENT, reserving the name TIDE for the vertical movement. See also SPRING TIDE, NEAP TIDE, MIXED TIDE; see also TIDAL DAY, TIDAL FLAT, TIDAL PRISM, TIDAL RANGE, TIDAL RISE, TIDAL WAVE, TIDE STATION
Tide station Getijstation A place at which tide observations are being taken. It is called a primary tide station when continuous observations are to be taken over a number of years to obtain basic tidal data for the locality. A secondary tide station is one that is operated over a short period of time to obtain data for a specific purpose.
Viscosity Viscositeit That molecular property of a fluid that enables it to support tangential stresses for a finite time and thus to resist deformation.