טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentKashinsky Dan
SubjectStudy of Safety in Roundabouts in Dual Carriageways
DepartmentDepartment of Civil and Environmental Engineering
Supervisor Professor Doron Balasha
Full Thesis text - in Hebrew Full thesis text - Hebrew Version


Abstract

Statistics in Israel shows a significant higher number of accidents in roundabouts placed in multilane roads than those of a single lane.

This paper tries to find whether or not the safety target is being achieved in full in all kinds of roundabouts, and if not so, to what extent and why this is the case in certain types of roundabout.

The existing situation in Israel was examined in two ways:

One, an analysis of characteristics of accidents taking place on roundabouts.

Two, examination of road-user behavior at these intersections through observations and analysis in same manner.

Obtaining a similar ratio of number of incidents and severity in different types of roundabouts and in ratio obtained of quantity and severity of accidents between different types of roundabouts can teach that what the observations reflect may correctly indicate relative accident potential of each type of roundabout.

In summary, A comparison of average accident figures shows that average weighted rate of accidents at full two-lane intersections is considerably higher, to a statistically significant degree, than that of all the other types of intersections and similar picture is obtained in the observed incidents but to more extreme values.

Together with that, we see that are obtained in the observations, but the trend is the same.

The following conclusions and recommendations were made:

?           The process of convergence in the approach is well covered in the planning instructions.

?           The phenomenon of side proximity can be attributed, at least in part, to the lanes being too narrow, both those in the instructions and those implemented in practice by the planners.

?           Consideration should also be given to pedestrians incidents in two interfaces with vehicle traffic.

It is recommended:

a.   To attempt to shorten length of pedestrian crossings to minimum possible.

b. To move pedestrian crossings back so that they are ‘behind’ the first vehicle waiting to enter the roundabout.

?           An approach of selective and gradual upgrading of single-lane roundabouts should be taken, similar to policy in Germany.