Ads
related to: river training apron width chart 1 8 20 explained
Search results
Results From The WOW.Com Content Network
Thus the chart coloration gave a clear indication to users as to whether they were using a chart with depths in fathoms or feet. While depths and heights were in metres, the nautical mile continued to be an international standard. Derived from the length of 1 minute of latitude, it is defined as 1852 metres. [12] [13] [14] [15]
A diagram showing how scour holes are formed. Bridge scour is the removal of sediment such as sand and gravel from around bridge abutments or piers. Hydrodynamic scour, caused by fast flowing water, can carve out scour holes, compromising the integrity of a structure.
On nautical charts, the top of the chart is always true north, rather than magnetic north, towards which a compass points. Most charts include a compass rose depicting the variation between magnetic and true north. However, the use of the Mercator projection has drawbacks. This projection shows the lines of longitude as parallel.
Training or entrance training refers to coastal structures built to constrain a river discharging across a littoral coast so that it discharges only where desired. Untrained entrances on sandy coasts tend to move widely and violently to discharge into the ocean, often upsetting those enjoying land nearby.
In the field, sedimentologists use graphical charts to accurately describe the sorting of a sediment using one of these terms. [1] Tangential sorting is the result of sediment being deposited in same direction as flow. Normal tangential sorting results in a gradient of sediment sizes deposited from largest to finest as they travel downstream. [2]
Armour of basalt blocks. In hydrology and geography, armor is the association of surface pebbles, rocks or boulders with stream beds or beaches.Most commonly hydrological armor occurs naturally; however, a man-made form is usually called riprap, when shorelines or stream banks are fortified for erosion protection with large boulders or sizable manufactured concrete objects.
The river regime generally refers to the mathematical relationship between the river discharge and its width, depth and slope. Thus, "river regime" describes a series of characteristic power-law relationships between discharge and width, depth and slope [ 1 ]
Gabion stepped weirs are commonly used for river training and flood control; the stepped design enhances the rate of energy dissipation in the channel, and it is particularly well suited to the construction of gabion stepped weirs. [2] A gabion wall is a retaining wall made of stacked stone-filled gabions tied together with wire.