scholarly journals Access Bridge Design Measures for Safety Increase of the Road Infrastructure

2013 ◽  
Vol 25 (6) ◽  
pp. 543-554 ◽  
Author(s):  
Tomas Micunek ◽  
Zuzana Schejbalova ◽  
Drahomir Schmidt
Keyword(s):  
Numerical Simulation ◽  
Detailed Analysis ◽  
Deformation Zone ◽  
Technical Solution ◽  
Drainage Ditch ◽  
Bridge Design ◽  
Passenger Car ◽  
The Road ◽  
Traffic Lane ◽  
Current Design

Solid barriers represent danger for the driver in case of traffic lane escape. This threat can be represented by a drainage ditch culvert face. The access bridge is not usually conspicuous enough near the traffic lane so that the driver could ditch and crash this barrier in case of an exceptional situation such as avoidance manoeuvres. This work deals with a technical solution of access bridges with an integrated deformation zone which was designed on the ground of a detailed analysis of current types of the construction. The new technical solution was proved by means of a numerical simulation of passenger car impact and compared with the current design of culvert faces.

scholarly journals Study of Traffic Volume and its Safety Measurement at Dadabari Circle, Career Point University, Kota

2018 ◽  
Vol 8 (01) ◽  
Author(s):  
Raj Pratap Singh ◽  
Himanshu Tekwani ◽  
Bhavesh Joshi ◽  
Pratheek Sudhakaran ◽  
Jitendra Singh
Keyword(s):  
Traffic Flow ◽  
Traffic Safety ◽  
Traffic Volume ◽  
Heterogeneous Traffic ◽  
Traffic Condition ◽  
Passenger Car ◽  
The Road ◽  
Traffic Lane ◽  
Wide Range ◽  
On The Road

The knowledge of traffic volume is an important basic input required for planning, analysis and operation of roadway systems. A significant effort has been made in order to study the Traffic Volume of Dadabari Chauraha. For better understanding of the present status of traffic flow at the junction, traffic survey is conducted. The safe and time efficient movement of the people and goods is dependent on Traffic flow, which is directly connected to the traffic characteristics. In Traffic Flow we have to consider generally three parameters, Volume, Speed, and Capacity. While as a traffic volume may be defined as the number of vehicles passing a given section of road or traffic lane per unit time will be inappropriate when several types of vehicles with widely varying static and dynamic characteristics are comprised in the traffic. Due to mixed nature of traffic it gets difficult to accommodate all the kinds of traffic on these roads. The basic problem arises during the peak hours of the day when the traffic volume is highest on the road. The interaction between moving vehicles under such heterogeneous traffic condition is highly complex. The problem of measuring volume of such kind of traffic has been addressed by converting the different types of vehicles into equivalent passenger cars and expressing the volume in terms of Passenger Car Unit (PCU) per hour. Calculation of Passenger Car Units (PCU’s) for different vehicle types had been made. For a wide range of traffic volume and roadway conditions indicate that the PCU value of a vehicle significantly changes with change in traffic volume and width of roadway. some of the remedial measures to improve the traffic safety in the region such as widening the road, changing 4-lane to 6-lane or by providing more public transport can be recommended based on the outcomes of the work.

Optimization of the characteristic angles of both front and rear McPherson suspensions on a circular track using multi-body numerical simulation

2009 ◽  
Vol 223 (9) ◽  
pp. 1119-1132 ◽  
Author(s):  
G Virzì Mariotti ◽  
G Ficarra
Keyword(s):  
Numerical Simulation ◽  
Contact Forces ◽  
Roll Motion ◽  
The Road ◽  
Virtual Vehicle ◽  
Circular Track ◽  
Characteristic Values ◽  
Optimal Values ◽  
Multi Body

The research reported in this paper aims to simulate the road-holding of a virtual vehicle using multi-body simulation to estimate both the contact forces between the tyre and ground and the roll motion when cornering. Furthermore, the effect of the characteristic angles on the variation in the forces of the tyre in contact with the ground is studied to determine optimal values for these angles. Emphasis is placed on an average-class vehicle, of which both the external dimensions and mass are chosen appropriately, with a McPherson suspension mounted on both the front and the rear. The characteristic values of the camber and toe-in angles, in both the front and the rear, are optimized for motion in the curve under constant traction. The results of numerical simulation are compared with results from the theory of stability in the curve (given the vertical configuration of the vehicle).

Improved Design of Vertical Curves with Sight Distance Profiles

2003 ◽  
Vol 1851 (1) ◽  
pp. 13-24 ◽  
Author(s):  
Yasser Hassan
Keyword(s):  
Design Procedure ◽  
The United States ◽  
Analytical Models ◽  
Minimum Length ◽  
Vertical Alignment ◽  
The Road ◽  
Sight Distance ◽  
Special Cases ◽  
Current Design ◽  
Improved Design

Design of vertical alignment is one of the main tasks in highway geometric design. This task requires, among other things, that the designer ensure drivers always have a clear view of the road so they can stop before hitting an unexpected object in the road. Therefore, the ability to determine the required and available stopping sight distance (SSD) at any point of the vertical alignment is essential for the design process. Current design guides in the United States and Canada provide simple analytical models for determining the minimum length of a vertical curve that would satisfy the sight distance requirement. However, these models ignore the effect of grade on the required SSD. Alternative approaches and models have also been suggested but cover only special cases of vertical curves. Two specific models were expanded to determine the required SSD on crest and sag vertical curves. By comparing profiles of available SSD and required SSD on examples of vertical curves, it was shown that current North American design practices might yield segments of the vertical curve where the driver’s view is constrained to a distance shorter than the required SSD. An alternative design procedure based on the models was developed and used to determine the minimum lengths of crest and sag vertical curves. Depending on the approach grade, these new values of minimum curve length might be greater than or less than values obtained through conventional design procedures. Design aids were therefore provided in tabular form for designers’ easy and quick use.

Investigation of Motorcycle Trajectories in 2-lane Horizontal Curves

2021 ◽  
Vol 16 ◽  
pp. 610-625
Author(s):  
Panagiotis Lemonakis
Keyword(s):  
Linear Equations ◽  
Great Accuracy ◽  
Design Guidelines ◽  
Road Segment ◽  
Small Radius ◽  
Horizontal Curve ◽  
Horizontal Alignment ◽  
The Road ◽  
Horizontal Curves ◽  
Traffic Lane

Most of the road design guidelines assume that the vehicles traverse a trajectory that coincides with the midline of the traffic lane. Based on this assumption the thresholds of various features are determined such as the maximum permissible side friction factor. It is therefore important to investigate the extent to which the trajectory of the vehicles is similar to the horizontal alignment of the road or substantial differences exist. To this end, a naturalistic riding study was designed and executed with the use of an instrumented motorcycle which measured the position of the motorcycle with great accuracy in a rural 2-lane road segment. The derived trajectories were then plotted against the horizontal alignment of the road and compared with the 3 consecutive elements which form a typical horizontal curve i.e., the entering spiral curve, the circular curve, and the exiting spiral curve. Linear equations were developed which correlate the traveled curvatures with the distance of each horizontal curve along the road segment under investigation. The process of the data revealed that the riders differ their trajectory compared to the alignment of the road. However, in small radius horizontal curves is more likely to observe curvatures that are similar to the geometric one. Moreover, the riders perform more abrupt maneuvres in the first part of the horizontal curves while they straighten the handlebars of the motorcycle before the end of the curve. The present paper aims to shed light on the behavior of motorcycle riders on horizontal curves and hence to contribute to the reduction of motorcycle accidents, particularly the single-vehicle ones.

Determining Passenger Car Equivalent for Motorcycle at Mid-Block of Sesetan Road

2015 ◽  
Vol 776 ◽  
pp. 95-100
Author(s):  
I. Gusti Raka Purbanto
Keyword(s):  
Motor Vehicles ◽  
Heavy Vehicles ◽  
Highway Capacity ◽  
Passenger Car ◽  
Highway Capacity Manual ◽  
The Road ◽  
Traffic Conditions ◽  
Mode Share ◽  
Passenger Car Equivalent ◽  
On The Road

Motorcycle dominates traffic in Bali, particularly in urban roads, which occupy more than 85% of mode share. The three types of vehicles, i.e. motorcycles, heavy and light vehicles share the roadways together. Under mixed traffic conditions, motorcycle may be travelling in between and alongside two consecutive motor vehicles. Considering such a situation, passenger car equivalent values should be examined thoroughly. This study aims to determine passenger car equivalent (PCEs) of motorcycle at mid-block of Sesetan Road. Three approaches are used to examine the PCEs values. This study found that the PCE of motorcycles are in a range between 0.2 and 0.4. This values are about the same to the existing PCE of the Indonesian Highway Capacity Manual (1997). This study also pointed out that motorcyclists and car drivers may behave differently to the existence of motorcycles. Car drivers are more aware than motorcyclists on the existence of motorcycle on the road. Further, more samples are required to obtain comprehensive results. In addition, the presence of heavy vehicles need to be considered for future study.

Effects of Speed Bumps and Humps on Motorcycle Speed Profiles

2014 ◽  
Vol 931-932 ◽  
pp. 536-540 ◽  
Author(s):  
Wichuda Satiennam ◽  
Thaned Satiennam ◽  
Pornsiri Urapa ◽  
Tussawan Phacharoen
Keyword(s):  
Developing Countries ◽  
Developed Countries ◽  
Vehicle Speed ◽  
Passenger Car ◽  
The Road ◽  
Acceleration Rate ◽  
Major Mode ◽  
Before And After ◽  
On The Road ◽  
Speed Humps

In developed countries, the use of speed humps and bumps have evolved from extensive research and testing which been properly designed and standardized. On the contrary in developing countries, no systematic and scientific studies have been carried out on that environment, especially the study on the effects that the motorcyclists response to the humps and bumps. This study therefore reveals the riders behavior when negotiating their speed to the devices. A case study was conducted in the provincial cities of Thailand where the motorcycle was a major mode of transportation. Six locations with speed humps and bumps were selected. Vehicles passing times were simultaneously recorded at 12 points along each traffic calmed link. From these data, a speed profile for each individual vehicle and for a link could be derived. It is found that speed humps and bumps have critically different impacts on motorcycle rider and passenger car driver. The smaller size speed bumps could effectively control the rider speed but have diverse impacts on the driver. These speed differences could post more safety deficiency to the site. The effect of the device on riders behavior, however, is restricted to a short spatial range (about 20-30 m before and after the device). For the speed humps, the motorcycle speeds are quite varied depending mainly on the road terrain. It is found that the motorcyclists have significant lower acceleration rate on the upgrade terrain when compared to the passenger car. Therefore, it is important to take all these rider characteristics into considerations when design the road humps to control vehicle speed in the developing countries.

A Multi-Point Tire Model for Studying Bridge–Vehicle Coupled Vibration

2016 ◽  
Vol 16 (08) ◽  
pp. 1550047 ◽  
Author(s):  
Lu Deng ◽  
Ran Cao ◽  
Wei Wang ◽  
Xinfeng Yin
Keyword(s):  
Numerical Simulation ◽  
Single Point ◽  
Point Contact ◽  
Road Surface ◽  
Dynamic Responses ◽  
Tire Model ◽  
Point Model ◽  
Disk Model ◽  
The Road ◽  
Dynamic Amplification

The contact between a vehicle tire and the road surface has been usually assumed as a single-point contact in the numerical simulation of vehicle–bridge interacted vibrations. In reality, the tire contacts the road surface through a patch instead of a single point. According to some recent studies, the single-point tire model may overestimate the dynamic amplification of bridge responses due to vehicle loadings. A new tire model, namely, the multi-point tire model, is therefore proposed in this paper with the purpose of improving the accuracy of numerical simulation results over the single-point model, while maintaining a certain level of simplicity for applications. A series of numerical simulations are carried out to compare the effect of the proposed tire model with those of the existing single-point model and disk model on the bridge dynamic responses. The proposed tire model is also verified against the field test results. The results show that the proposed multi-point tire model can predict the bridge dynamic responses with better accuracy than the single-point model, especially under distressed bridge deck conditions, and is computationally more efficient and simpler for application than the disk model.

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