Technique & Economy Evaluate And Select On Ningbo-Xiangshan Harbour Cross-sea Bridge And Tunnel Proposals

To meet the needs of the rapid social and economic development in Ning Bo and to better up the investment environment, fully playing the integrated function of the city Agglomeration in the south wing of the Changjiang River Delta, it has been an urgent requirement to build a cross-sea passage to promote the road transportation system from Xiangshan to Ning bo, to relieve the traffic stress and solve the existing problems. The article has put forward a selection through comparisons between the bridge and tunnel proposals on the basis of a thorough investigation and research on the construction conditions of the Xiangshan Harbour and by borrowing the experience from the cross-sea bridge and tunnel projects both in china and abroad.This article gives systematic illustrations on the general theory and methodology of the methods, procedure, the elements for comparing the technical features of the comparison of bridge and tunnel proposals and the financial evaluation on the project, public economic evaluation and analysis on some uncertainness. It also introduces the special social and natural environment of the Ningbo-Xiangshan Harbour cross-sea passage, the geologic structure and fault activity, requirements for navigation and makes a preliminary analysis and research on the fundamental technical requirements of the bridge and tunnel constructions, gives a brief introduction of the influence of the project on the current traffic and prediction to the future traffic and the result of distribution, works out the construction scale of this project considering the traffic capability.The article firstly chooses the stayed-bridge and NATM methods for the comparison of bridge and tunnel proposals through various designs, evaluations and comparisons on different bridge sites, bridge types and the methods of construction. Then it makes a deep comparison in terms of the traffic organization and sustainable development, cost of the project, operation and maintenance costs and finds that the bridge proposal is better from the technical point of view. In the end, the article finds out that the stayed-bridge method has strong capabilities of gaining profits and anti-risks not only in view of this project but of the national economy, while the tunnel method has weak capability of gaining profits and little anti-risk capability.Considering the results of technical and economic evaluations, the article draws a conclusion that the stayed-bridge proposal should be applied to the Ning bo-Xiangshan Harbour Cross-sea passage. At the same time, it is suggested the government should give support both in policy and finance in fund collection and entrust the relative research departments to do specific research in the wind-proof aspect of the bridge proposal and fulfill the wind-proof methods.It is expected that the illustration of this article on comparison of bridge and tunnel proposals can give certain inspiration and guidance to the other cross-water passage projects especially the cross-sea passage projects, to choose the suitable proposal according to the reality and do the project in a safe and effective way. The conclusion of the article has provided scientific evidence for the decision-making of the project construction methods and made it clear about the reasons to recommend the bridge proposal and has solved the practical problems of the project.