城市隧道近接施工对既有公路的营运影响研究

针对城市新建地下通道下穿既有公路的工程情况,采用三维数值模拟手段对既有公路路面纵横向影响范围和应力分布特征及洞周的位移、应力随隧道开挖的动态变化规律进行了研究,得到了既有公路在隧道下穿过程中的最危险区域,路面底部很有可能会产生受拉破坏,同时隧道内侧拱顶将产生沉降,拱底将产生隆起等结论性成果,进而提出了保证既有公路正常运营和新建隧道安全施工的方法、监测手段和加固措施。

ANALYSIS ON THE INFLUENCE ON THE NEARBY EXISTING-ROADWAY OPERATION DURING CITY TUNNEL 'S EXCAVATION

Considering the situation of new-build tunnel underpassing the existing road,the 3-D numerical simulation method was chosen to study the affected area of the road longitudinal and cross surface,the distributing feature of stress,the tunnel perimeter deflection and dynamic change of the stress during the tunnel＇s excavation.Some results were gained,such as： most dangerous sections under the road during in tunnel construction,the tension damage likely occurring on the road bottom surface,settlement of the inner part of the tunnel arch crown and upheaval of tunnel bottom.Based on the results,the construction,monitoring and strengthening method are proposed to ensure the normal operation of the existing roadway and the new-build tunnel safety.