Combined with the example of the Junchang Tunnel of Censhui Expressway in the middle and Guangxi section of Baomao Expressway, this paper briefly introduces the four major mud and water inrush disasters that occurred, and expounds the causes of the disasters. Consolidation excavation of the tunnel has made a summary of construction technology.

Based on the author's experience in the past twenty years, this paper describes the construction process of membrane structure of space structure. The construction process of long-span tensioned membrane structure is mainly introduced.

The experience of developed countries shows that digital economy can promote high -quality economic development. By constructing a comprehensive evaluation index system, this paper measures the digital economy and high quality economic development level of Zhejiang province from 2013 to 2019. First, the coupling model is used to measure the dynamic evolution process of digital economy and high-quality economic development, then the general linear linear regression model is fitted to explore the promotion degree of digital economy to high-quality economic development, and finally, the mediationeffect model is used to analyze the mechanism of digital economy to promote high -quality economic development. The following conclusionsare drawn: In recent years, the development level of digital economy in Zhejiang province continues to improve, and the coupling coordination degree of digital economy and high-quality economic development gradually reaches a good level. Digital economy can promote high-quality economic development. Every 1% increase in the level of digital economy will increase the level of high-quality economic development by 0.4694%. The index of scientific and technological innovation is taken as a mediating variable, and the test model is constructed. The mediating effect is found to be significant, which indicates that digital economy empowers scientific and technological innovation to promote high-quality economic development. Based on this, this paper puts forward some suggestions to provide reference for thehigh quality economic development of Zhejiang Province.

Due to the rapid development of cities and the acceleration of urbanization in recent years, various policies and plans have been issued one after another. However, many plans are not coordinated and unified, which leads to the imbalance of urban development. Therefore, urban and rural planning begins to transform to land and space planning. The new land space planning system has made a series of important instructions for urban restoration and urban ecological restoration. The “double repair” of the city has become an urgent problem to be solved. At the same time, the “double evaluation” system is used to measure the current situation of urban development. This paper deeply explores the ecological restoration of arid city under the land space planning system of Lanzhou as an example. Through the ecological restoration concept put forward under the land space planning system, at the same time, learning from the new evaluation system, it puts forward new solutions for the urban ecological restoration of Lanzhou. From the perspective of sustainable development, the mode of urban ecological restoration in Lanzhou is deeply optimized, and the new direction of urban development in Lanzhou is deeply adjusted from three aspects of mountain, water and urban overall development.

According to the example of University restaurant, in order to improve the service ability, the industrial engineering method is used to optimize the meal purchasing process and restaurant layout. Considering the process random events, queuing, popular routes and other factors, the simulation model is established by using Flexsim software. The data are collected by field measurement and random sampling, and the data distribution is verified by maximum likelihood estimation method and goodness of fit test method, and the simulation parameters are calculated. The simulation results show that the optimized model can serve 124 people more than the current model in one hour, and the working rate of the four checkout counters has been improved, which proves that the optimized scheme can effectively alleviate the crowd congestion, improve the service ability, and provide data support for the implementation of the optimization scheme.