Traffic Flow Modeling and Simulation of Signalized Intersections

Abstract

In this paper, based on traffic flow characteristics of urban highways and discreteness 才 theory of numerical analysis, a series of traffic models including traffic generation model, car-following model, and lane changing models were built to study microscopic traffic flow simulation and calculation methods of urban road signal controlled intersections. Then a numerical simulation C++ program was coded on Linux platform using discrete mesh method after determining a reasonable traffic flow simulation parameters, and simulation results were verified using traffic survey data analysis. Finally, the basis for how to optimize urban road intersections congestion state and how to make decisions about traffic management and control of signalized intersections were provided, and the optimized way The urban transport system is composed of pedestrian, vehicles, roads, environment, and other factors. It is a dynamic system and it has complex structure, with multiple influencing factors, randomness, and unstable factors. In recent years, with the improvement of people's living standards, the urban vehicles and resident trips have been increased. This led to serious urban traffic congestion, dropped traffic speed, increased traffic accident rate, and environmental pollution. It has become a bottleneck that restricts the development of the urban economy. The intersections are the joints of the urban road network, and the study of the road intersection is the key to solve the traffic problems in the city. The actual capacity of intersection and vehicle delay time are an important indicator of the evaluating operation efficiency and service level of the intersection (1). In this paper, firstly, the intersection layout model, traffic generation and operation model, and signal control model were built to analyze the actual situation of the intersection and traffic characteristics. Then, based on these models, an urban road intersections traffic flow simulation program was developed and conducted with numerical simulation. Finally, the simulation model and modeling platform were verified by using a large number of field survey data. 2. Traffic Flow Modeling In this paper, traffic flow discrete model is considered in the fully discrete ideas of cellular automata and classic GM model (2) at the same time. Its basic idea is the road network will be divided into a number of square grids with the same size, length, and width of each grid representing certain distances. Roads are composed of several grids that merge together according to certain rules. The different grid cell represents a different size of vehicle. Grid length is defined as average space headway when blocked. The speed unit is m/s, the time step in this study is 1 second. CICTP 2015