在2000年初的Nazzano隧道（A1高速，毗邻罗马）扩宽工程中，首次尝试在不影响既有交通的情况下进行高速公路隧道的扩宽，而非更改线路或采用施工中降低隧道交通服务水平的方法。该工程证明了Nazzano工法的可行性和有效性，采用该工法最大限度地减少了土地占用量，在扩展干线公路、高速公路或铁路基础设施能力时，在建筑施工期间能够不降低其服务水平。由于其他方案（如开挖第3条隧道或在加宽车道处封闭交通）将增加更多的经济和社会成本，因而这种能够不干扰交通的隧道扩宽方案已成为投资方一种可靠有利的选择。

Widening a motorway tunnel in the presence of traffic without resorting to alternative routes or reductions in the level of service was attempted for the first time in the world in the early 2000s to widen the Nazzano Tunnel (A1 Motorway, near Rome). The completion of the project constituted without doubt a true milestone for tunneling. It demonstrated the feasibility and efficiency of the method, which by reducing land consumption to a minimum, made it possible to expand the capacity of strategic road, motorway or rail infrastructures without reducing the level of service during construction operations. The solution to widen the existing tunnel without interrupting traffic has now become a reliable and advantageous option for clients where possible alternatives (driving a third tunnel or closing traffic in the carriageway to be widened) can be more financially and socially costly than widening the existing tunnel.