Search results
Results from the WOW.Com Content Network
Drainage gradient (DG) is a term in road design, defined as the combined slope due to road surface cross slope (CS) and longitudinal slope (hilliness). Although the term may not be used, the concept is also used in roof design and landscape architecture. If the drainage gradient is too low, rain and melt water drainage will be insufficient.
If one looks at red numbers on the chart specifying grade, one can see the quirkiness of using the grade to specify slope; the numbers go from 0 for flat, to 100% at 45 degrees, to infinity as it approaches vertical. Slope may still be expressed when the horizontal run is not known: the rise can be divided by the hypotenuse (the slope length).
Cross section of a road. 1. Gutter; 2. Shoulder; 3. Sub-base; 4. Base course; 5. Asphalt. Cross slope, cross fall or camber is a geometric feature of pavement surfaces: the transverse slope with respect to the horizon.
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 modern mapping, a topographic map or topographic sheet is a type of map characterized by large-scale detail and quantitative representation of relief features, usually using contour lines (connecting points of equal elevation), but historically using a variety of methods.
Drainage density is a quantity used to describe physical parameters of a drainage basin. First described by Robert E. Horton , drainage density is defined as the total length of channel in a drainage basin divided by the total area, represented by the following equation:
the design drain spacing (L) can be found from the equation in dependence of the drain depth (Dd) and drain radius (r). Drainage criteria One would not want the water table to be too shallow to avoid crop yield depression nor too deep to avoid drought conditions. This is a subject of drainage research.
The slope of the water table is known as the “hydraulic gradient”, which depends on the rate at which water is added to and removed from the aquifer and the permeability of the material. The water table does not always mimic the topography due to variations in the underlying geological structure (e.g., folded, faulted, fractured bedrock).