偏压荷载对箱型明洞受力影响及设计要点

为研究偏压荷载对箱型明洞结构受力影响，为该类明洞结构的设计提供理论依据，以某道路开孔箱型明洞工程为例，采用ANSYS有限元数值模拟方法进行计算分析,综合研究结果表明： 1）偏压回填箱型明洞靠山侧墙底部和外侧墙顶部受力较大，设计配筋时需要加强； 2）靠山侧墙背回填土侧压力对明洞结构受力影响较大，改善回填材料内摩擦角大小可以有效降低明洞结构内力，当内摩擦角增大到47°时最为经济； 3）可以通过在明洞洞顶回填EPE的方式减轻洞顶冲击荷载，降低明洞内力，最优回填厚度为0.9 m。

Force Influence of Asymmetrical Pressure on Box type Shed and Design Points

The study of the force influence of asymmetrical pressure on box type shed structure is very important to provide theoretical basis for some similar projects. As a result, a road shed is taken for an example to carry out calculation and analysis by ANSYS finite element numerical simulation method. The results show that: (1) The bearing force on the bottom of the side wall and the top of the outside wall of the box type shed with eccentric backfilling is relatively large, which need to be strengthened in the design of reinforcement. (2) The lateral stress of backfilled soil on mountain side has a great influence on the structure of the shed; the structure internal force of the backfill can be improved by grouting to reduce the internal force of the shed; the economic benefits can be the highest when the internal friction angle reaches 47°. (3) The backfill of EPE on top of open tunnel can reduce the load impact on tunnel top and the internal force, and the optimal backfill thickness is 0.9 m.