Public Private Partnership (PPP) mode is increasingly applied in civil air defense (CAD) projects to improve project quality and reduce the government’s financial pressure. Because CAD project has different attributes during wartime and peacetime states, it’s necessary to comprehensively consider the project performance under different states to conduct scientific performance measurement. This paper focuses on the process of construction, operation, and handover of CAD PPP project to construct a unified project performance measurement indicator system, then a system dynamics (SD) model is established to carry out dynamic performance measurement and simulation of CAD PPP project under different social states respectively. A case study is conducted to verify the effectiveness of the proposed SD model, model validation, sensitivity analysis and result analysis were included as well. The study result can make the project performance management of CAD PPP more scientific and reasonable, and help decision-makers to formulate effective performance improvement strategies. It’s found out that government plays an important role in CAD PPP projects, when resources are limited, the government should give priority to measures such as reducing tax rates and increasing subsidies to ensure project benefits. The research methods can also provide reference for performance measurement of other PPP projects.

Deep foundation pit (DFP) projects have been a high incidence area of safety accidents because of their own high danger and complexity. Therefore, it is necessary to study the resilience of their construction safety system. This paper systematically identifies the key factors affecting the resilience of deep foundation pit construction based on the analysis of the composition of the deep foundation pit construction safety system (DFPCTSS), the synergistic relationship of its subsystems in the face of the interference and impact of internal and external disaster-causing factors, and the causal mechanism of typical accidents in DFP accidents and the emergent process of system resilience. A resilience evaluation indicator system based on four capacity dimensions of prevention absorption, resistance, recovery, and learning adaptation was constructed by using the fuzzy Delphi method, which is characterized by the resilience emergence process. Then the correlation and weight of evaluation indexes were analyzed based on the DEMATEL–ANP method, the boundary cloud parameters of the resilience evaluation grade were set according to the normal extension cloud model, and the membership degree of the resilience evaluation level was calculated to complete the evaluation of the resilience level. Finally, taking a DFP project of a metro station as an example, the above model was used to evaluate the resilience level of its construction safety system, and suggestions for resilience enhancement were put forward. The results show that the evaluation results are consistent with the actual situation of the project, and the evaluation model is conducive to providing a systematic analysis method and improvement countermeasures for deep foundation pit construction safety management from the perspective of resilience.

Slurry balancing shield construction is a method in which slurry pressure and groundwater pressure are balanced to achieve stability of excavation working face. It is widely used in tunnel construction due to its safety and high-efficiency characteristics. At present, research on safety risk management of slurry balancing shield construction is relatively lacking, and most scholars still mainly focus on technical research. In this paper, based on system engineering theory and from the perspective of whole construction process, a comprehensive evaluation index system for shield construction risk analysis is built by taking “human-machine-material-method-environment” as assessment dimensions. This paper modifies the existing analytic hierarchy process (AHP), combines AHP with fuzzy synthetic evaluation to build a risk analysis model, and quantifies the construction risk by evaluation set and matrix. Combined with case study, the effectiveness of the proposed model is verified, and measures to mitigate safety risks of slurry shield construction are proposed from perspectives of management, economy, and technology. This paper evaluates the overall risk level of project from a systematic perspective, which is an extension of traditional technology-oriented research.

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