scholarly journals Dynamic Modelling of the Effects of Combined Horizontal and Vertical Curves on Side Friction Factor and Lateral Acceleration

2019 ◽  
Vol 471 ◽  
pp. 062001 ◽  
Author(s):  
Ali Abdi ◽  
Parshad Aghamohammadi ◽  
Reza Salehfard ◽  
Vahid Najafi ◽  
Moghaddam Gilani
Keyword(s):  
Friction Factor ◽  
Dynamic Modelling ◽  
Lateral Acceleration ◽  
Side Friction Factor ◽  
Side Friction

scholarly journals Fenomena Lalu Lintas Simpang Bersinyal di Kota Bekasi (Studi Kasus: Simpang Tol Bekasi Timur)

2016 ◽  
Vol 11 (4) ◽  
pp. 195
Author(s):  
Yuanda Patria Tama
Keyword(s):  
Friction Factor ◽  
Traffic Flow ◽  
Public Transportation ◽  
Street Vendor ◽  
Characteristic Factor ◽  
Bus Stop ◽  
Traffic Law ◽  
Road Space ◽  
Side Friction Factor ◽  
Side Friction

The transportation’s problem that common in Indonesia is a limitation of road space and intersection that needed to conduct the traffic flow. An accident and degradation of intersection’s performance, it’s caused by the driver’s attitude which have a less concern to the traffic law. This research attempt to observe the driver violation which influences the characteristic of urban’s intersection to find out the phenomenon of traffic’s signal intersection. The strategy to design the intersection in East Bekasi highway for reducing driver violation by using the side friction factor that consists of extending the radius of junction sleeves, constructing lay bay in bus stop, demolition the street vendor, ojek base and public transportation. Also, the geometric intersection factor consists of installation signs, marka reparation, constructing the pedestrian facility, and specific stopping area for motorcycle, then the traffic’s characteristic factor consists of an intensive supervising by policeman, constructing the priority track to turn left on red and installation signs.

Comfort thresholds for horizontal curve design

2009 ◽  
Vol 36 (9) ◽  
pp. 1391-1402 ◽  
Author(s):  
Dalia Said ◽  
Yasser Hassan ◽  
A.O. Abd El Halim
Keyword(s):  
Research Work ◽  
Lateral Acceleration ◽  
Horizontal Curve ◽  
Driver Behaviour ◽  
Rural Roads ◽  
Speed Reduction ◽  
Horizontal Curves ◽  
Friction Factors ◽  
Side Friction Factor ◽  
Side Friction

A key to better geometric design of highways is designing horizontal curves conforming to driver behaviour. The values of side friction factors in the point mass formula, used for the design of the minimum radius of a horizontal curve, are based on the upper threshold of driver comfort. In the current guidelines, these driver comfort levels were established in research work carried out back in the 1930s. Recently, it was found that faster drivers tend to accept higher comfort thresholds to maintain their speed and minimize speed reduction between curve and tangent. An experiment was designed at Carleton University to collect newer data on driver behaviour including speed and lateral acceleration. The results confirmed the need to revise the values of side friction demand especially for sharp curves. In addition, a model was developed to determine the side friction factor to be used in design or in consistency evaluation of horizontal curves on rural roads and ramps.

scholarly journals KAJIAN KINERJA PERSIMPANGAN TIDAK BERSINYAL (STUDI KASUS : PERSIMPANGAN TIGA GADUT, JALAN RAYA INDARUNG – BANDAR BUAT, KOTA PADANG)

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Eko Prayitno ◽  
Veronika Veronika
Keyword(s):  
Traffic Flow ◽  
Environmental Data ◽  
Degree Of Saturation ◽  
Road User ◽  
Total Delay ◽  
The Road ◽  
Traffic Conditions ◽  
Road Capacity ◽  
Side Friction Factor ◽  
Side Friction

The highway is one of the infrastructure for the smooth traffic. One part of the road that are considered necessary to be analyzed and evaluated is an intersection. Three Gadut intersection is non signalized intersection. The traffic flow is quite dense, and lack of discipline of road user factors competing space to pass the crossing, resulting in congestion is very influential on traffic conditions at peak hours in the morning, afternoon and evening. Prior to conducting the survey, the first to do is survey the condition of the intersection that includes geometric characteristics and traffic volume. From the analysis of environmental data, side friction factor to the junction of three Gadut is the criteria being. Rated capacity (C) the smallest is 3706.3 smp/hour, the degree of saturation of 1.1 smp/hour. This value is over the limit permitted values manually indonesian road capacity of 0.8 to 0.9 (1.1> 0.9), it is concluded that the traffic flow is the crossroads of three Gadut saturated traffic flow. The queue probability value between 128.8% - 157.4% with a total delay largest average 11.57 seconds/smp. It is concluded that the chances of a queue at the intersection of three Gadut very large, so it could cause congestion.

Kinematic Approach to Horizontal Curve Transition Design

2000 ◽  
Vol 1737 (1) ◽  
pp. 1-8 ◽  
Author(s):  
James A. Bonneson
Keyword(s):  
Control Process ◽  
Vehicle Control ◽  
Design Guidelines ◽  
Lateral Shift ◽  
Lateral Acceleration ◽  
Horizontal Curve ◽  
Traffic Lane ◽  
Kinematic Models ◽  
Side Friction ◽  
Kinematic Approach

Research has shown that vehicles shift laterally in the traffic lane during their entry to (or exit from) a horizontal curve. In addition, research indicates that most drivers momentarily adopt a path radius that is sharper than that of the roadway curve. A study was undertaken to investigate the causes of lateral shift and sharp path radii and to determine if they can be minimized (or eliminated) by modifying the horizontal curve transition design. From a review of the driver–vehicle control process, it was concluded that lane shift is due to unbalanced lateral accelerations that act on the vehicle as it enters the curve. These accelerations result from gravity, as effected through roadway superelevation, and side friction, caused by the steer angle of the vehicle. Kinematic models of lateral acceleration, velocity, and shift were developed. The calibrated models were used to develop design guidelines for superelevation rate and superelevation runoff location.

scholarly journals Improved methods for distribution of superelevation

2021 ◽  
Author(s):  
Udai Hassein
Keyword(s):  
Optimization Model ◽  
Safety Margin ◽  
Highway Design ◽  
State Highway ◽  
Safety Margins ◽  
Single Arc ◽  
The Difference ◽  
Design Consistency ◽  
Side Friction Factor ◽  
Side Friction

The American Association of State Highway and Transportation Officials (AASHTO) provide 5 methods for distributing highway superelevation (e) and side friction (f). Method 1 (linear) is inferior to Method 5 (curvilinear). AASHTO Method 5 deals with speed variations, but its complex mathematical calculation affects design consistency. Safety margin is the difference between design and maximum limiting speed. This thesis describes distribution of superelevation (e) and side friction factor (f) based on the EAU and SAU methods using AASHTO and two different curves from the unsymmetrical curve; the equal parabolic arcs "EAU Curve" and a single arc unsymmetrical curve "SAU Curve". The thesis also describes e and f distributions based on the optimization model. The EAU and SAU methods and Parametric Cubic Optimization Model improve highway design consistency based on safety margins. Examples show the methods and optimization model are superior to AASHTO methods.

scholarly journals Improved methods for distribution of superelevation

2021 ◽  
Author(s):  
Udai Hassein
Keyword(s):  
Optimization Model ◽  
Safety Margin ◽  
Highway Design ◽  
State Highway ◽  
Safety Margins ◽  
Single Arc ◽  
The Difference ◽  
Design Consistency ◽  
Side Friction Factor ◽  
Side Friction

The American Association of State Highway and Transportation Officials (AASHTO) provide 5 methods for distributing highway superelevation (e) and side friction (f). Method 1 (linear) is inferior to Method 5 (curvilinear). AASHTO Method 5 deals with speed variations, but its complex mathematical calculation affects design consistency. Safety margin is the difference between design and maximum limiting speed. This thesis describes distribution of superelevation (e) and side friction factor (f) based on the EAU and SAU methods using AASHTO and two different curves from the unsymmetrical curve; the equal parabolic arcs "EAU Curve" and a single arc unsymmetrical curve "SAU Curve". The thesis also describes e and f distributions based on the optimization model. The EAU and SAU methods and Parametric Cubic Optimization Model improve highway design consistency based on safety margins. Examples show the methods and optimization model are superior to AASHTO methods.

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