Optimizing Road Network Density Considering Automobile Traffic Efficiency: Theoretical Approach

In recent years, the planning idea of denser road networks and smaller blocks has received particular interest from planners and researchers. However, what is the impact of road network density on the efficiency of automobile traffic? Does a denser road network operate better? To address these questions, we develop an analytical approach taking the influence of intersection delay into account in this research. It is proved that there exists an optimal road network density that maximizes the average travel speed and travel production simultaneously under a given vehicle accumulation. When determining the reasonable road network density, the optimal density under peak-hour vehicle accumulation can be an important reference but not the final choice. If the peak-hour traffic fluctuates acutely, a denser road network should be considered for providing higher reliability. If the peak period is quite short, a sparser road network may be a better choice for providing higher travel speed as well as higher travel production during off-peak periods.