弃土场对浅埋隧道结构安全的影响研究

Impact of a Waste Soil Disposal Site on the Safety of a Shallow Buried Tunnel

人口密集区高速公路建设过程中存在弃土场选址受限、结构安全与生态防护要求标准高的特点。结合某浅埋隧道上方设置弃土场案例,运用等效覆土厚度方法与Boussinesq附加应力求解方法分别计算确定了弃土场不同堆渣高度时作用于隧道结构的附加荷载,进而应用荷载结构法对隧道二衬结构安全进行分析。研究表明,等效覆土厚度方法较Boussinesq方法计算得到的隧道结构受力偏于安全,并提出弃土场对浅埋隧道结构安全影响评估的建议方案。

Waste soils are frequently generated in the expressway construction projects.In the densely populated area,the selection of the waste soil disposal is constrained by the environmental and stability requirements.This paper presents a case history of evaluation of the effect of a waste soil site on a shallow burred tunnel.Both the equivalent soil thickness method and the Boussinesq effective stress method were used to estimate the effective stress acting on the tunnel structures with different waste soil heights.The performance of the tunnel liners under the additional stress was also analyzed.It is concluded that the equivalent soil thickness is more conservative than the Bousinesq solution.The evaluation approach of the effect of waste soil on the structural safety of the shallow buried tunnel is also suggested in the paper.