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  2. Geometric design of roads - Wikipedia

    en.wikipedia.org/wiki/Geometric_design_of_roads

    The alignment is the route of the road, defined as a series of horizontal tangents and curves. The profile is the vertical aspect of the road, including crest and sag curves, and the straight grade lines connecting them. The cross section shows the position and number of vehicle and bicycle lanes and sidewalks, along with their cross slope or ...

  3. Grade (slope) - Wikipedia

    en.wikipedia.org/wiki/Grade_(slope)

    Grade is usually expressed as a percentage - converted to the angle α by taking the inverse tangent of the standard mathematical slope, which is rise / run or the grade / 100. 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 ...

  4. International roughness index - Wikipedia

    en.wikipedia.org/wiki/International_roughness_index

    The international roughness index (IRI) is the roughness index most commonly obtained from measured longitudinal road profiles. It is calculated using a quarter-car vehicle math model, whose response is accumulated to yield a roughness index with units of slope (in/mi, m/km, etc.).

  5. Pavement condition index - Wikipedia

    en.wikipedia.org/wiki/Pavement_Condition_Index

    The pavement condition index (PCI) is a numerical index between 0 and 100, which is used to indicate the general condition of a pavement section.The PCI is widely used in transportation civil engineering [1] and asset management, and many municipalities use it to measure the performance of their road infrastructure and their levels of service. [2]

  6. Drainage gradient - Wikipedia

    en.wikipedia.org/wiki/Drainage_gradient

    Typically on straight road sections, the drainage gradient is at least 1–3% due to the normal cross slope of 1–3%. In curved sections the drainage gradient is higher, and may often reach 5–12% due to superelevated CS that may reach 5–8% in areas with icy roads and up to 12% in areas without icy roads.

  7. Interstate Highway standards - Wikipedia

    en.wikipedia.org/wiki/Interstate_Highway_standards

    Pavement sloping: On straight sections of the highway, the roadway is to have a cross slope of at least 1.5%, and preferably 2% to ensure proper drainage, with up to 2.5% in areas of heavy rainfall. The cross slope of both the left and right shoulders should be between 2% and 6%, but not less than the main lanes.

  8. Roughness length - Wikipedia

    en.wikipedia.org/wiki/Roughness_length

    This provides a method to calculate the roughness length by measuring the friction velocity and the mean wind velocity (at known elevation) in a given, relatively flat location (under neutral conditions) using an anemometer. [4] Of note is that, in this simplified form, the log wind profile is identical in form to the dimensional law of the wall.

  9. Pavement Surface Evaluation and Rating - Wikipedia

    en.wikipedia.org/wiki/Pavement_Surface...

    The PASER scale is a 1-10 rating system for road pavement condition developed by the University of Wisconsin-Madison Transportation Information Center. PASER uses visual inspection to evaluate pavement surface conditions. When assessed correctly, PASER ratings provide a basis for comparing the quality of roadway segments. [1]