Motorway junction design with emphasis on traffic performance and safety assesment - case study junction Ljubljana Rudnik

Thesis encompasses reconstruction predesign of the motorway junction Ljubljana Rudnik into motorway interchange. In this area is intended to be the junction of main arterial road with highway network, while today serves only as a minor junction of Rudnik and Ig area on the motorway. The purpose of reconstruction is to enable free traffic flow on most congested directions of the interchange, but also preserve the present function, in which Ig and Rudnik area are connected with the motorway. But we also want to add another function of merging new arterial road with motorway network.\ud In the first part we have introduced terminology regarding interchanges, ramps and intersections, including theorethical bases for planning and design. We have focused on the meaning of hearing area and determined the conditions for roadway spatial planning.\ud Based on the traffic demand study, for the planning year 2035, we have chosen a collection of characteristic interchange forms. We estimared the level of service of chosen section of interchange for critical movements. We used Highway capacity software (HCS+) which is based on Highway capacity manual 2000. The four most appropriate variants were detailed analysed with software VISSIM 5.30. With the help of the program we determined the number of lanes on ramps and other roads. We chose the most appropriate variant for this case by comparitive analysis, where we compared variants also in the meaning of traffic safety. We use SSAM 2.1.6 software for traffic safety impact assesment. For each variant we estimated the number of potential conflicts between the vehicles.\ud After »traffic comparison« we checked the construction possibilities and necessities for four chosen variants. We designed longitudional profiles for each ramp of the interchange for every variant. Then we estimated the lengths of needed overcoming structures for each case and physical possibility to build them in limited urban space. We roughly estimated the length of new roads and the size of the area used for roadways and bridges. We used surveying data in digital form and AutoCAD Civil 3D software for making a rough predesign of the interchange.\ud After all the comparisons we have made, we then decided which variant is the most appropriate and adequate for this case. The chosen form will be in the next phase thoroughly designed and optimized but that is no longer the part of this thesis