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The article analyzes the comprehensive development levels of the three subsystems of Chongqing's tourism, urbanization and ecological environment from 2000 to 2017, and the temporal evolution characteristics of the coordinated development of the three. The results show that: (1) The comprehensive evaluation index of Chongqing's tourism industry system and urbanization system is on the rise; the comprehensive ecological environment index showed an upward trend before 2008, and fluctuated greatly after 2008. (2) The degree of coupling and coordination of the three systems in Chongqing City generally shows a transformational trend of maladjustment recession-intermediate transition-coordination improvement. In the future, Chongqing should continue to deepen institutional reforms and continue to develop new tourism markets; improve transportation, promote enterprise transformation and upgrading, implement policies for talent introduction; strengthen the construction of environmental protection talents and capital investment, and vigorously develop ecological industries

Construction solid waste has become an important environmental pollution source in the city, and the treatment and application of construction solid waste has become the focus of attention. Construction waste recycled aggregates have defects such as high water absorption and micro cracks, which affect its extensive application. In order to improve the utilization rate of recycled aggregates, the influence of different replacement rates of recycled aggregates on the mechanical properties of concrete is studied in this paper. The results show that with the increase of replacement rate of recycled aggregates, the 3-day, 7-day and 28-day compressive strength, splitting strength and cohesive force of concrete decrease gradually, but the mechanical properties of concrete decrease slowly at 3 days and 7 days, and decrease obviously at 28 days. Moreover, with the increase of replacement rate of recycled aggregates, the decline trend of mechanical properties is not obvious. Compared with natural aggregate concrete, the 28-day compressive strength, splitting strength and cohesive force of 100% recycled aggregate concrete are reduced by 16.1%, 20.1% and 18.1% respectively, but the mechanical properties meet the requirements of C30 concrete, which provides a reference for engineering application.