Highway Engineering Questions

• Highway engineering (flexible pavements): What is the minimum thickness of the base course in a flexible pavement as typically adopted in practice and IRC-based design guidelines?
• Camber selection on straight roads: For a straight road with a thin bituminous surfacing (surface dressing/OGPC type), what is the desirable camber range to ensure adequate drainage without causing discomfort?
• Highway organization: Under whose direct control does the Executive Engineer (Roads) execute works in a typical PWD hierarchy?
• Geometric standards for hill roads: What is the normal formation width adopted for a hill road carrying one-way traffic?
• Terminology check: The practice of raising the outer edge of a roadway relative to the inner edge on a horizontal curve is known as what?
• Traffic signs (route markers): From the point of tangency (PT) before an intersection, at what typical distance are route marker signs installed to give adequate advance guidance?
• Super-elevation formula for hill road curves: If V is the design speed in km/h and R is the radius of a horizontal curve (m), what relationship correctly expresses the required super-elevation when combined with side friction?
• History of road engineering: Who is credited with developing road making as a systematic building science leading to the “macadamized” road?
• Hill road structures: The wall provided on the valley (downhill) side to stabilize and retain the backfilled portion of the roadway embankment is called what?
• Constructing super-elevation: What is the most commonly adopted method of providing super-elevation on roads during construction?
• Traffic engineering – factors governing the capacity of a single-lane highway For a single traffic lane, the practical traffic carrying capacity depends primarily on which of the following field factors?
• Highway gradients – where are “floating gradients” generally adopted? A floating gradient is the minimum downgrade at which a vehicle can continue at a constant speed without engine tractive effort. On an alignment, such gradients are generally provided:
• Road shoulders – typical design width On standard highways, the width of each shoulder provided alongside the carriageway is generally kept at which value?
• Vertical curve equation – upgrade g1% followed by downgrade g2% For a parabolic vertical curve of length L (measured horizontally), joining an initial grade of g1% to a final grade of g2%, the elevation y at a distance x from the point of curvature (PVC) is expressed as:
• Traffic flow – theoretical maximum vehicles per hour from spacing and speed If vehicle length is L metres and the clear distance between successive vehicles is C metres, moving at a speed V km/h, the theoretical maximum flow N (vehicles per hour) is:
• Highway drainage – typical side drain width in hilly regions What is the usual (typical) width provided for roadside side drains along highways in hilly terrain?
• Determinants of pavement (carriageway) width The selected pavement width for a road section primarily depends upon which factors?
• Medians – minimum desirable widths in practice Which of the following statements about median width provisions is correct for rural highways and long bridges/viaducts?
• Traffic measurements – use of an enoscope An enoscope (periscope-type roadside device) is primarily used to measure which traffic parameter?
• National Highways – minimum pavement (carriageway) width The minimum width of the paved carriageway (pavement) provided for a standard two-lane National Highway is typically: