Study On Characteristics And Optimization Measures Of Urban Fitness Trails Thermal Environment In Tianjin

The rapid development of our society and the static,sedentary lifestyle and work patterns have led to numerous chronic diseases.In the 14 th Five-Year Plan and the "Healthy China" strategy,the State has clearly proposed to promote the construction of outdoor sports spaces.As an important part of the exercise space,the comfort of fitness trails is of great significance in improving the quality of life of residents and building a high-quality living environment.In terms of quantity,quality and performance,it still fails to meet people’s needs,and its construction and evaluation standards lack a scientific basis,so it is necessary to carry out systematic research.From the existing results,the existing research objects are too large in scale and vague in function,and there is a lack of small-scale space thermal comfort evaluation studies,ignoring the movement characteristics and subjective demand differences of the active people.In view of this,this study aims to understand the thermal environment of small-scale fitness trails and the influence mechanism of environmental elements,fully understand the thermal demand characteristics of different activity groups,establish evaluation criteria for the thermal comfort of urban fitness trails in Tianjin,and propose measures to optimization the thermal environment of fitness trails,so as to improve the quality of this environmental space,which carries exclusive functions,in a targeted manner.In this study,several representative fitness trails were selected according to the differences in various combinations of environmental elements.(1)The thermal environment of fitness trails in winter and summer was measured to understand the thermal environment characteristics of urban fitness trails in Tianjin and the influence of various elements(plant forms of tree,shrub and grass combinations,shading methods,degree of green shading SVF,type of substrate,distance and orientation of water bodies,mountains,etc.)on the thermal environment.(2)Through a questionnaire survey of the trail activity population in winter and summer,the thermal demand characteristics of the trail activity population,the preference of thermal environment parameters and the difference in thermal sensitivity of people in different exercise states were grasped,and a thermal comfort evaluation model was established for the fitness trail in winter and summer,and thermal neutral temperature and comfort temperature ranges were established.(3)Through correlation analysis,the differences in subjective comfort and thermal neutral temperature characteristics of people with different activity metabolic amounts were clarified,and the effect of different activity metabolic amounts on thermal sensation and thermal comfort was further grasped,as well as the correlation strength of metabolic amounts and trail space shading patterns with thermal sensation,thermal comfort and thermal environment parameters.Based on the comfort temperature range calculated by the thermal comfort evaluation model and the thermal demand characteristics of the trail activity population,the outdoor thermal environment of urban fitness trails in Tianjin is quantified and analysed with this objective.After fully verifying the applicability and accuracy of the simulation software,the thermal environment optimisation measures of fitness trails are proposed and the performance of the trail thermal environment is simulated.The research results can complement the evaluation system of thermal comfort of smallscale outdoor functional spaces in cities,and provide accurate evaluation of the thermal comfort of people with different metabolic amounts on the trails,hoping to provide useful reference and methodological guidelines for the high-quality construction of urban fitness trails.