This project belongs to other technical fields. Research results of the project This result is based on the completion data of the river-crossing tunnel completed during the "Eleventh Five-Year Plan" period, summarizing, analyzing and changing laws of the technical and economic indicators of the river-crossing project. The research results can be used as the basis for investment control in cross-river tunnels and urban road underground passages.
The main highlights and innovations of the project research:
1、 Systematic summary for the first time: This research is the "first time" in China to comprehensively summarize and analyze the technical and economic indicators of urban road tunnels. The results are extensive, representative and professional.
2、 Digitalize the design drawings: various technical parameters such as the form and length of the enclosure structure, and the size of the main structure (floor, roof, side walls, etc.) in the plan and section are reflected in the "Structural Feature Table", realizing the "digitization" of the design drawings.
3、 Serialization of tunnel projects: Based on the technical parameters such as the diameter of the circular tunnel, single or double tube, single or double layer and the number of lanes of the circular tunnel, the open section, concealed section, working well and circular tunnel sections are classified, and the open section, concealed section, and working well are divided into four categories, and the circular tunnel is divided into three categories.
4、 Conduct modular analysis of the investment structure: 1) Conduct modular analysis based on the nature of the investment. The tunnel project is divided into four levels of indicator systems: single item, unit, division and sub-item economic indicators. 2) Conduct modular analysis based on the structural characteristics of tunnel engineering. The tunnel project is divided into open-cut section and circular tunnel section; the open-cut section is divided into rectangular tunnels and working shafts; the open-cut section is divided into enclosure structures, earthworks, main concrete structures, foundation reinforcement, etc.; the circular tunnel section is divided into indicator systems for shield tunneling, segment prefabrication, internal structure, etc.
5、 Apply the concept of "space" to analyze the change laws of technical and economic indicators: In addition to analyzing the laws of technical and economic indicators based on length and area, the concept of "space (excavation)" is also used to measure technical and economic indicators.
6、 Exploration of costs related to shield machinery: The shield-related costs (shield amortization, etc.) of existing projects are itemized and sorted out, and reasonable suggestions are put forward to provide a basis for reasonably determining the costs when preparing cost documents in the future.
7、 Analysis of the change law of investment in tunnel projects: Analyze the change law of investment in tunnel projects (price index) since January 2003, the proportion of labor, materials and machinery costs in project costs, and the sensitivity analysis of changes in labor, materials and machinery prices to changes in project costs, etc.; Through these research and analysis, it is convenient to reasonably determine the project cost when preparing cost documents, effectively control investment, how to avoid the potential risk factors of "losing control" of investment due to price changes, and find key points to control investment.
8、 "Critical depth" between various foundation pit reinforcement schemes: The analysis draws the analysis conclusion that "the investment of various foundation reinforcement schemes is related to the depth of the foundation pit" and has "critical depth". At the same time, the economic index formula of various foundation reinforcement schemes is provided.
9、 Rapid estimation of engineering investment: "Special Analysis of Rapid Estimation of Tunnel Engineering Investment"(sub-topic 9) integrates the analysis results of technical indicators and economic indicators to explore how to establish a "mathematical model" of tunnel engineering investment; in the research report, there are four rapid estimation methods: "table" and "formula", of which "formula" is used for the first time in tunnel engineering.
A total of 10 papers related to the research content of the topic were published. The research results have reached the international advanced level and have been successfully applied to the rationality of the bidding control price of the "Zhoujiazui Road River-Crossing Tunnel New Project" and the rationality of the investment estimate of the feasibility study of the "Longshui South Road River-Crossing Tunnel New Project", saving about 69 million yuan in national investment. The promotion of the results has economic benefits of more than 10 billion yuan and has far-reaching impact and significance on the future investment control of cross-river tunnels.