This project belongs to the field of civil construction. Large public buildings are important functional hubs of cities. Due to long-term use, building aging and functional decline, more and more public buildings are facing the need for upgrading. For important public buildings such as commercial complexes, museums, stations, and airports, the suspension of business and renovation will have a significant impact on urban functions and social economy. Therefore, the uninterrupted operation and renovation of large public buildings has become a common demand. Aiming at the problems of difficulty in operating guarantee under uninterrupted operation conditions of large public buildings, difficulty in ensuring safety under high-density pedestrian flow environments, and difficulty in green construction under high-standard operation requirements, this project has formed uninterrupted operation of large public buildings through independent innovation and engineering practice. Key technologies for reconstruction. The main innovative results are as follows: 1. An evaluation method for non-business renovation operation guarantee for optimal functional needs. In view of the problems of complex functions of large public buildings and high requirements for uninterrupted operation support, effective assessment of uninterrupted operation and reconstruction construction risks was achieved by analyzing the relationship between operational function support and construction processes, quantifying construction impact weights and indicators; a dynamic division technology based on minimum intervention principle was established; based on transportation organization planning, equipment pipeline utilization, construction safety and other technologies, a dynamic conversion technology between construction areas and operation areas was formed.  2. Traffic guarantee and compensation technology based on intelligent monitoring and simulation analysis of people and vehicles. Based on video surveillance, intelligent sensing and image recognition technology, a people-traffic density monitoring technology based on image and big data analysis has been established, which has realized automated and accurate statistics of people and traffic; a traffic simulation model of public buildings has been established, which has been used to analyze the characteristics of traffic operations through macro and micro multi-level analysis to realize prediction of traffic operation conditions under reconstruction conditions; a dynamic traffic organization and guarantee technology based on road overturns, switching, flow compensation, etc. has been formed.  3. Screening and compensation technology for complex equipment pipelines under conditions of incomplete information. In response to the problems of complex equipment pipelines and incomplete information in large public buildings, based on three-dimensional scanning, geological radar, electromagnetic induction and other technologies, equipment pipeline layout and screening technology has been established to realize the identification and positioning of complex equipment pipelines. By analyzing the impact of functional support between equipment pipelines and operation areas, an equipment pipeline regional correlation analysis and evaluation technology was formed; and a dynamic switching of equipment pipelines based on the combination of switching, compensation and permanent presence of electromechanical equipment and municipal pipelines was established. Compensation technology.  4. Green construction and safety assurance technology under uninterrupted operation conditions. Based on the principle of minimum interference, safety protection and isolation technologies that are integrated with the operating environment have been formed, which not only ensures personnel and traffic safety, but also reduces the impact of reconstruction and construction on the comfort of the operating environment. Green, miniaturized and suitable construction processes and equipment have been developed, achieving effective control of sound and light dust pollution and the goal of waste reduction. Structural safety assurance technology based on time-varying analysis and remote intelligent safety monitoring technology based on BIM and the Internet of Things have been established to ensure structural safety under the transitional transformation of the stressed system during structural reconstruction.  The project has obtained 15 nationally authorized patents (including 8 invention patents), completed 15 construction methods (including 1 national-level construction method and 3 Shanghai-level construction methods), published 1 paper, and transformed 1 high-tech achievement in Shanghai City. The scientific research results have reached the international advanced level through expert appraisal and scientific and technological novelty search. The results of the project have been applied to more than 10 renovation projects such as the China Art Palace, Shanghai Museum, Hang Lung Plaza, Ganghui Plaza, First Eight Hundred Companions, Shibaidian, World Trade Plaza, Pacific Department Store, and China Resources Times Square. Economic benefits are approximately 750 million yuan. This project has promoted the development of uninterrupted operation and reconstruction technology for large public buildings and has wide promotion and application value.