加宽五车道和三车道不对称小近距隧道设计

Design of widened five-lane and three-lane unsymmetrical and closely-spaced tunnels

随着交通运输的迅速发展,超大断面小近距高速公路隧道或城市快速干道的建设将成为发展的重点。福州市机场二期隧道初步设计定为加宽五车道,无论是洞室跨度还是设计施工难度均属全国公路隧道之首。对于超大断面隧道来说,扁平率不但直接影响工程造价,而且对结构设计和施工带来新的问题。文章主要通过结构受力和经济比选内轮廓,并通过有限元计算,分析隧道设计的合理性。

With rapid development of communication, tunnels with super- large cross -section and closelyspaced tunnels on highways or urban main roads will be adopted more than ever. The tunnel on airport highway phase Ⅱ of Fuzhou city was preliminarily designed to be with widened 5 lanes, which would rank the first among national highway tunnels in terms of cross - section and the difficulties in design and construction. For tunnels with super- large cross -section, ratio of rise to span is the main factor that affects the cost of the tunnel project and brings about problems to structural design and construction. This article performed structural analyses by FEM and economical comparison for the internal peripheries to justify the rationality of the tunnel design.