城市地下工程中常遇到软弱围岩近接问题。深圳市丰盛町地下街D区就是软岩超浅埋近接跨越既有隧道的典型工程，它在垂直下穿埋设有大量地下管线的深南大道的同时上跨两孔地铁区间隧道，其最小埋深仅3.9m，结构跨度13.7m，地下街底部与地铁隧道顶部的净距仅为0.33m，地层变形控制十分困难。针对丰盛町地下街D区的工程特点，根据设计和施工方案，运用有限差分软件FLAC3D进行三维数值模拟，预测地下街施工引起的地层变形及地铁区间隧道变形以验证方案的合理性，总结出软岩超浅埋近接跨越既有隧道地层变形分布规律，为今后类似工程提供借鉴。

New underground works that are located in soft ground with close proximity to existing underground works are often encountered. The D district of Fengshengding underground street tunnel in Shenzhen is a typical urban underground works that passes over existing tunnels in soft ground with small spacing. The underground street tunnel passes underneath Shennan road, where a lot of utility lines are buried, and at the same time passes over two Metro tunnels. The minimum overburden of the underground street tunnel is 3.9m and the structural span of the underground street tunnel is 13.7m. The spacing between the bottom of the underground street tunnel and the roof of the Metro tunnel is only 0.33m. Therefore it is very difficult to control the ground deformation. In order to verify the rationality of the design and construction scheme of this project, the authors predict the deformation of the ground and Metro tunnels by threedimensional numerical simulation made by FLAC3D, based on the characteristics and design and construction scheme of the project. The authors conclude the deformation distribution regulation of extrashallow underground works passing over existing tunnels with small spacing, which can provide reference for similar projects in the future.