O Appearance and ComfortAppearance is an important consideration for both small and large changes in grade, similar to crest curves.Sag vertical curves are generally designed to meet comfort criteria at a minimum:Unlit rural and urban roads: Sag curves should ideally be designed to satisfy headlight sight distance requirements.Highways and freeways: Sag curves are typically designed to exceed he..

O K valueWhat is a K value?It's a number that describes the size of a vertical curve on a road.It tells how many meters of curve are needed for every 1% change in slope.Why use K values?They make it easy to calculate the curve's radius at the top: R=100K.The radius and K value give almost the same result for normal road slopes.How are K values used?Road authorities might give you the K value to ..

O Sight Distance Parameters - Object height - Driver eye height - Reaction time  O Longitudinal Deceleration : Longitudinal deceleration measures the friction between tires and the road, influenced by factors like speed, surface type, and condition, with a standard coefficient of d = 0.36 for most roads and d = 0.46 reserved for low-volume, constrained roads.O  Headlight Sight DistanceOn unlit r..

O Vehicle Speeds on Roads(km) > High : 90~ > Inter : 70~90 > Low : ~70 O  Design Speed and Operation Speed > 85th Percentile Speed (Operating Speed)This is the speed at or below which 85% of vehicles travel under free-flowing conditions.It reflects the actual driving behavior of most drivers. > Design SpeedThis is the speed used to determine the road's geometric features (e.g., curve radius, sig..

Import data : file - Datainput - xyz general- parameters : company usually have their own parameter fileglass icon - read filePencil icon - write file- filefolder icon - open - excel file of dataexcel [1(point ID), 2(Xcoordinate), 3(Ycoordinate), 4(Zcoordinate), 5(String name), 6(String number)]- Basictext style- Format- Mapfile- folder icon - open - Basic(layer )Fencing-Read - Finished : import..

'·reference : wsudcompliance.com.au / Austroads guide to road design part 5A 1. piped Network Element ㅇ Dranage inlets - Capture surface runoff - control flodded limits(With, Depth, WxD) - redirect flows underground into pipe network ㅇ Access chambers - Provide access for maintenance - Changes of direction, grade, level - At pipe junctions ㅇ pipes - convey captured runoff from inlets - Multiple ..