跨海大桥施工用电费用计算和经济性比较

Calculation and Economic Comparison of Electricity Cost for Construction of Cross-sea Bridge

我国跨海大桥工程项目逐渐增多,其投资优化问题引起业界关注,随着施工机械化水平的提升,跨海大桥用电量随之增加,用电费用在跨海大桥总投资中的影响比重随之提升。本文在分析铁路建设工程施工用电费用计算方法的基础上,针对杭州湾跨海铁路大桥提出利用地方电源的全线贯通电缆供电方案和海上发电平台分散发电方案,分别计算两种方案的用电方案总费用并进行对比。本文提出确定桥梁施工用电方案经济性的临界长度法,对其他类似的跨海大桥项目施工用电方案的选择提供参考。得到结论:跨海大桥长度越大或单位长度用电量越大,利用地方电源的全线贯通电缆供电方案相较于海上发电平台分散发电方案经济性越明显。

China’s cross-sea bridge engineering projects are increasing gradually,and the issue of investment optimization has attracted the attention of the industry.With the improvement of construction mechanization level,the electricity consumption of cross-sea bridges will increase,and the proportion of electricity costs in the total investment will follow promote.Based on the analysis of the calculation method of the construction electricity cost of the railway construction project,this paper proposes a full-line through cable power supply scheme using local power sources and an offshore power generation platform decentralized power generation scheme for the Hangzhou Bay Cross-sea Railway Bridge.The power schemes and total cost of the two schemes are calculated and compared separately.This paper proposes the critical length method to determine the economic efficiency of the bridge construction power plan,and provides a reference for the selection of other similar cross-sea bridge projects.It is concluded that the greater the length of the sea-crossing bridge or the greater the electricity consumption per unit length,the more economical the power supply scheme of the full-line through cable using local power sources will be compared to the distributed power generation scheme of offshore power generation platforms.