Study on the impacts of urban network evolution on urban wind and heat environment based on improved genetic algorithm

Study on the impacts of urban network evolution on urban wind and heat environment based on improved genetic algorithm

Bohong Zheng Yanfen Zhong 

College of Architecture and Art, Central South University, Changsha 410076, China

College of Civil Engineering and Architecture, Nanchang Hangkong University, Nanchang 320063, China

Corresponding Author Email:
31 October 2018
| Citation



The irrational layout of urban space is very likely to produce urban heat island (UH). Thus, it is highly necessary to explore how the evolution and spatial distribution of urban network affect the urban wind and heat environment (W&HE). In this paper, an improved genetic algorithm (GA) is proposed to simulate the evolution of urban network, and the UH intensities (UHIs) of Changsha, China are monitored at 18 urban and 7 suburban observation points. On this basis, the author analysed the impacts of urban spatial layout on the W&HE and the UHI. The results show that: the improved GA is feasible for simulation and analysis of the evolution trend of urban network; the UH effect increased with the total urban area and building floor-area ratio (FAR); the mean daytime UHI in downtown Changsha decreased with the growth in green space ratio and increased with the growth in the hardened ground ratio. Therefore, the urban spatial layout should be planned rationally to control the development intensity, lower the ratio of hardened ground and expand the green space in the urban area. The research findings lay a solid theoretical basis for the optimal design of urban layout and the improvement of urban W&HE.


urban network, urban space, wind and heat environment (W&HE), urban heat island (UH) effect, improved genetic algorithm (GA), backpropagation neural network (BPNN)

1. Introduction
2. Urban space and application of improved AG
3. Relationship between urban form and the UH effect
4. Urban network and urban W&HE
5. Conclusions

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