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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. International roughness index - Wikipedia

    en.wikipedia.org/wiki/International_roughness_index

    Roughness progression for a road in Texas, US. Blue dots show the times of maintenance. 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 ...

  4. 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]

  5. 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 ...

  6. 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.

  7. 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]

  8. Present serviceability index - Wikipedia

    en.wikipedia.org/wiki/Present_Serviceability_Index

    The PSI was developed based on the AASHO Road Test's present serviceability rating (PSR). AASHO Road Test was a set of experiments carried out by the AASHTO from 1956 to 1961. [4] Unlike the PSR, which was a ride quality rating that required a panel of observers to ride in a car over the pavement of interest, the PSI does not require a panel of ...

  9. Topographic Abney level - Wikipedia

    en.wikipedia.org/wiki/Topographic_Abney_Level

    The scale is reversible. As shown in the photo, it is set for measuring percent grade. The reverse measures degrees of arc. An Abney level and clinometer is an instrument used in surveying which consists of a fixed sighting tube, a movable spirit level that is connected to a pointing arm, and a protractor scale. An internal mirror allows the ...