2 Horizontal Alignment Minimum Radii Horizontal Curve Full Circle (FC) Tugas 3Spiral Circle Spiral (SCS) Tugas 4Spiral Spiral (SS) Tugas 4Sight Distance on Curve Tugas 5Stopping Sight Distance (SSD)Passing Sight Distance (PSD)Widening on Curve Tugas 5Superelevation Diagram Tugas 6Stationing Tugas 6
11 Geometric Design… normally seeks to ensure uniformity of alignment and maximum levels of safety and comfort for drivers using the road, within given economic constraints. Compromise are inevitable to achieve an acceptable solution and not all objectives can be fully met. Often, however, it is possible to improve road safety implications of design features are considered at the design stage.
26 Azimuth, Intersection Angle, distance between PI
27 Latihan Pilih 2-3 PI yang bersebelahan, Coba desain tikungan pada PI tersebut dengan jenis FC.
28 Tugas 3 Azimuth, D, distance between PI Minimum radius Curve type FC Stopping Sight DistanceWidening on curveStationingSuperelevation diagramAutoCAD drawingDikumpulkan via , Minggu 23 Ags 09 (pk. 12:00) dan CDRW, Senin 24 Ags 09 (pk. 12:00) di TU Sipil
29 Tiga Macam Lengkung Horisontal TCCTTSSCCSSTSSPIFull Circle (FC)Spiral-Circle-Spiral (SCS)Spiral-Spiral (SS)
36 TRANSITION (Spiral) CURVE To provide a natural, easy-to-follow path for drivers, where centrifugal force increase/decrease gradually.To provide a convenient desirable arrangement for superelevation run-off.To provide a flexible change in lane-width.To enhanced the appearance of the highway, to avoid the noticeable breaks at the beginning and ending of circular curves
37 Tangent Runout is the general term denoting the length of highway needed to accomplish the change in cross slope from a normal section to a section with the adverse cross slope removed, or vice-versa.2%0%2%2%0%2%
38 Superelevation Runoff, is the general term denoting length of highway needed to accomplish the change in cross slope from a section with adverse crown removed to a fully superelevation section, or vice-versa.2%2%0%2%2%0%
41 Minimum Length of Transition Sections Minimum Maneuver Time for Traveling on Transition Curve [RSNI T p.30].LS = (Vr/3,6) x tVr design speed (km/h)t running time (2 sec)
42 Minimum Length of Transition Sections Minimum Length of Superelevation Runoff [RSNI T p.30].LS = W 1/D (ed + eNC)LS = W 1/D ed AASHTOD relative slopes ratio (m/m)W road width (m)eNC normal cross fall (%)ed design superelevation (%)
61 Latihan Pilih 1-2 PI yang tidak memenuhi syarat desain FC, Coba desain tikungan pada PI tersebut dengan jenis SCS atau SS.
62 Tugas 4 Azimuth, D, distance between PI Minimum radius Curve type SCS & SSStopping Sight DistanceWidening on curveStationingSuperelevation diagramAutoCAD drawingDikumpulkan via , Minggu 30 Ags 09 (pk. 12:00) dan CDRW, Senin 31 Ags 09 (pk. 12:00) di TU Sipil
64 S = 15.9 d x f ±e x B% Braking Distance ! 100% Braking – Four Wheel Lock-up Skid or full ABS – Where f = 0.75 and S = 80km/hrFront Brakes Only – 70% d = 48 metersRear Brakes Only – 30% d = 112 metersOne Front Brake – 35% d = 96 metersOne Back Brake – 15% d = 225 meters !!!The distance required to skid to stop changes with the amount of braking power. The formula is multiplied by the percentage of the braking power expressed as a decimal. This is a good exercise for the students as they have to rearrange the equation and solve for “d.”
79 Widening on Curve A traffic lane on a curve must be widened because: The rear wheels do not track the front wheelsVehicle’s front overhang requires an additional lateral spaceDifficulty of driving on curves justifies wider lateral clearance
81 Widening on Curve Wn width of traveled way on tangent, m. U track width of vehicle (out-to-out tires), m.C lateral clearance per vehicle assumed 0,6/0,75/0,9 for Wn of 6,0/6,6/7,2 respectivelyFA with of overhang, m.Z extra width allowance for difficulty of driving on curves, m.u track width on tangent (out-to-out) 2,6m.R radius of centerline of 2-lane highway, m.L wheelbase, m.A front overhang, m.V design speed of highway, km/h.
83 Potongan Melintang Rencana Tipe Jalan : Kolektor SekunderKecepatan Rencana : 40 KphKendaraan Rencana : Single Unit (SU)
84 LatihanPilih 2-3 PI,Periksa syarat Stopping Sight Distance dan kebutuhan Widening on Curve.
85 Tugas 5 Azimuth, D, distance between PI Minimum radius Curve type Stopping Sight DistanceWidening on curveStationingSuperelevation diagramAutoCAD drawingDikumpulkan via , Minggu 6 Sep 09 (pk. 12:00) dan CDRW, Senin 7 Sep 09 (pk. 12:00) di TU Sipil
94 Tugas 6 Azimuth, D, distance between PI Minimum radius Curve type Dikumpulkan via , Minggu 13 Sep 09 (pk. 12:00) dan CDRW, Senin 14 Sep 09 (pk. 12:00) di TU SipilAzimuth, D, distance between PIMinimum radiusCurve typeStopping Sight DistanceWidening on curveStationingSuperelevation diagramAutoCAD drawing