Road Landscape Morphology of Valley City Blocks under the Concept of “Open Block”—Taking Lanzhou City as an Example

Zeng Zeng,Qian Qian,Xu Xu,Wei Wei,Ren Ren

doi:10.3390/su11226258

Abstract

The unique valley geographical environment and the congestion-prone road landscape make valley city traffic jammed easily. In this paper, under the background of “open blocks”, two open patterns, which correspond to two different road landscapes ("ideal grid opening" and "open under realistic conditions"), are proposed. Taking Lanzhou city as an example, six basic statistical characteristics are used to compare and analyze the changes of road network topology in blocks to find out which open pattern is more suitable for valley cities. The results show that the pattern "open under realistic conditions" has a significant effect on the improvement of network performance and capacity. Specifically, breaking the "large blocks" and developing the small-scale blocks help to alleviate the traffic pressure. Besides, the opening of blocks located along river valley has a more positive effect on improving road network performance than the blocks sited in the inner area of cities.

Highlights

In Lynch’s urban image theory, road and blocks are two main elements that people perceive the overall image of the city [1]
The internal road system of the block presents an introverted tree structure, only one or two main roads are connected to the outside urban road network
These closed neighborhoods cut off the “capillary vessels” of the urban road network, so that the traffic flow is concentrated on a few main roads of the city, which leads to regional paralysis of the traffic system once traffic jams occur in the main roads [4]

Summary

Introduction

In Lynch’s urban image theory, road and blocks are two main elements that people perceive the overall image of the city [1]. The closed block mainly refers to the neighborhood where the internal road system is closed to the outside world. The internal road system of the block presents an introverted tree structure, only one or two main roads are connected to the outside urban road network. These closed neighborhoods cut off the “capillary vessels” of the urban road network, so that the traffic flow is concentrated on a few main roads of the city, which leads to regional paralysis of the traffic system once traffic jams occur in the main roads [4]

Results

Discussion

Conclusion