Urban parks are an important component of urban public green space and a public place where a large number of urban residents choose to conduct outdoor activities. An important factor attracting people to visit and stay in urban parks is its outdoor thermal comfort, which is also an important criterion for evaluating the liability of the urban environment. In this study, through field meteorological monitoring and a questionnaire survey, outdoor thermal comfort of different types of landscape space in urban parks in Chengdu, China was studied in winter and summer. Result indicated that (1) different types of landscape spaces have different thermal comforts, (2) air temperature is the most important factor affecting outdoor thermal comfort; (3) because the thermal sensation judgment of outdoor thermal comfort research in Chengdu area, an ASHRAE seven-sites scale can be used; (4) the neutral temperature ranges of Physiological Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI) in Chengdu in winter and summer were obtained through research; (5) and UTCI is the best index for evaluating outdoor thermal comfort in Chengdu. These findings provide theoretical benchmarks and technical references for urban planners and landscape designers to optimize outdoor thermal comfort in urban areas to establish a more comfortable and healthy living environment for urban residents.

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Under air-conditioning intermittent operation, there may be the large difference of air temperatures in two adjacent rooms due to different operation behavior, and thereby, interior envelops may cause great heat loss. Under this condition, floors may become the most vulnerable spot of the room heat preservation due to their large proportion in interior envelops and poor thermal insulation. To optimize the thermal performance of floors, three floor models were built to compare their thermal performance characteristics under air-conditioning intermittent operation, while a heat transfer model was built by the finite volume method and verified by experimental data. The results showed that an expanded polystyrene layer located close to the upper surface can improve the thermal performance of the bottom floor, while the continuous integration of an air space ceiling placed close to the lower surface can improve the thermal performance of the top floor obviously. The daily cooling load formed by the cast-in-place-reinforced concrete floor integrated with the expanded polystyrene layer and the air space ceiling can reduce the daily cooling load by 53.27% and 47.00%, compared with the cast-in-place-reinforced concrete floor and the cast-in-place-reinforced concrete floor only integrated with the expanded polystyrene layer.

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