Reasonable traffic demand forecasting is the premise and guarantee of excellent traffic planning scheme, and an important technical support to treat urban traffic problems. With the continuous development of computer and Internet technologies, WebGIS technology is becoming more and more mature and widely used in all kinds of occupations. Therefore, the application of WebGIS in traffic demand forecasting and the innovation of demand forecasting means are of great significance to the innovation of traffic demand forecasting means. This paper focuses on the fourth stage of demand forecasting - traffic assignment. Firstly, the paper analyzes the key technical points to complete traffic assignment process, and proposes 3 the shortest path algorithms with centroid links; Secondly, the paper analyzes how to apply WebGIS to traffic assignment, and develops user-equilibrium assignment algorithm based on WebGIS. Finally, by comparing WebGIS-based assignment algorithm with TransCAD, the reliability of user-equilibrium assignment based on WebGIS is proved. This paper has important practical and theoretical value for further research on the four-stage forecasting process on the Web.

CICTP