Highway Engineering III (Intersection Design and Operation)

It is a compulsory core course of Direction of Transportation Engineering (optional in case of secondary direction) - 8th semester. The aim of the course is to acquire knowledge on the basic design and operation authorities of at-grade non-signalized and seperated grade interchanges. This knowledge is necessary for the investigation, proposal and evaluation of urban traffic regulations (priority nodes or circular) and interurban roads. The first section of the course includes geometric design concepts of at-grade non-signalized and seperated grade interchanges. Then, the course deals with designing data nodes through the description of the critical road data and the assessment of the level of operation of at-grade non-signalized and seperated grade interchanges. In this course the knowledge of the geometric design acquired in the completed course Highway Engineering I (geometric design of roads) is further extended. Furthermore, the knowledge of the assessment of the functional status of road infrastructure acquired (road sections) in Highway Engineering II course is enriched. Apart from the presentations of the individual modules, a visit to Attiki Odos Control Center is carried out which suggest the usefulness and application of the acquired knowledge for the operation of the center. This course includes: Design of at-grade and separated grade interchanges. Traffic capacity and operation level of junctions with priority. Traffic capacity and operation level of roundabouts. Traffic capacity and operation level of imports/ exports from highway. Road safety elements. The course is taught in the School of Rural and Surveying Engineering in National Technical University of Athens.

Objectives

The main objective of the course is to acquire knowledge on the basic design and operation authorities of at-grade non-signalized and grade separated interchanges.

Prerequisites

The knowledge acquired from the courses "Highway Engineering I" and "Highway Engineering II" is prerequisite for this course.

Syllabus

At-grade intersections: Introduction. Design criteria. Distances between nodes. Basic types of at-grade intersections. Occupancy surfaces of vehicles. Configuration of isolines. Altitude configuration. Extensions of road surface. Selection and configuration of mandatory lanes for turn movements. Types and configuration ways of islets and drops. Visibility. Pedestrian movement. Equipment. Accesses. Signaling. Capacity of non-signalized intersections. Operation of exclusive and non-exclusive lanes of turn movements. Roundabouts (rotundas). Grade Separated Intersections. Introduction. Categories and types of interchanges. Selection criteria. Types of connecting branches. Typical cross sections. Manoeuvres. Diverging. Merging. Weaving areas. Acceleration / deceleration lanes. Configurations of inputs and outputs to and from main branches. Vertical signaling. Capacity analysis on ramps. Traffic control in input branches on a highway.