Discussion On Environmental Preference Of Roof Greening In Commercial Buildings ——A Case Study Of Commercial Center In Chengdu City

With the continuous improvement of China’s urbanization level,the building density in cities keeps increasing,and people have less and less opportunities to contact nature.Meanwhile,the rapid development of cities makes urban commercial complex expand in the urban commercial central area like bamboo shoots after a spring rain,and the volume is huge.As a component of commercial complex building,roof greening is also an effective supplement to urban green space.The demand for roof greening in urban construction and the particularity of commercial buildings began to synchronize to form a benign development.At present,the research on roof greening in China mainly focuses on the planting of plants,drainage,treatment of roof structure and other structural measures,but there is still a lack of research on the environmental aesthetic scale involved in the use of roof greening and the targeted research on the user preference of commercial building roof greening.This paper takes the rooftop greening of commercial buildings in downtown Chengdu as the research object,and combines AHP with SBE beauty evaluation method to further analyze whether the two are related to the landscape environment of rooftop greening itself from the perspective of public perception and user experience from the perspective of user activity behavior.Sample based on the case to the ecological environment of the commercial building roof greening landscape construction analysis to evaluate and use the analysis of the status quo,put forward commercial building roof greening the landscape environment in the crowd preferences of optimization,in order to maximize the environmental benefits,in order to help the practical application of commercial building roof greening in the future,and using for reference.The results show that:（1）Through the index weight analysis of landscape evaluation model,ecological evaluation（0.4434）> aesthetic evaluation（0.3874）> social evaluation（0.1692）,it shows that the ecological value of plants is very important in landscape structure,and the ecological construction of plant landscape should run through the whole roof greening construction.Building the visual aesthetic feeling of landscape is also an important design content of roof greening,followed by improving the social service function of roof greening to meet the needs of users on the site.（2）Through the clustering analysis of users’ activity behaviors in the activity plots,the21 plots can be divided into three categories: sports and fitness,farm play and recreation.Among them,recreational recreation is the most popular type of roof greening.（3）Based on the comparison and analysis of SBE method and AHP method,combined with the clustering results of site use mode,and considering the landscape reconstruction focusing on environmental preference,it is concluded that the rooftop greening landscape of play-based farm sites is not performing well and needs to be optimized and transformed.（4）As for the significant characteristics of correlation between landscape factors and beauty value,it is known that improving landscape color change and collocation can affect the value of beauty value to the greatest extent.Therefore,in the design of roof greening,colorful plants can be made full use of or the outdoor decoration that harmonizes with the environment to increase the promotion of beauty.（5）For landscape factors significantly associated with using activity that landscape factors in the positive and negative correlation of the field is slightly different because of the use of the site type,is that the user on the use of the site activities led to certain environmental preferences,when the environment landscape in support role,the use of people behavior,is showing a positive correlation,negative conversely related effects.（6）Some landscape factors cannot support multiple use modes at the same time.For example,for the roof greening with sports and fitness functions,excessive plants and the environment with color changes will negatively affect the main use functions.In view of the limited scale of urban roof land,especially for commercial buildings,it is necessary to rationally arrange the layout and arrange the spatial function division in the process of design and planning,so as to improve the efficiency of roof greening.