基坑通风竖井支护设计及效果评价

Design and Effectiveness Evaluation of Ventilation Shaft Support for Foundation Pits

为确保基坑竖井的施工安全,文中结合竖井勘察成果,在开展其支护设计的基础上,进一步结合现场变形监测成果,通过变形预测评价其支护效果。结果表明,基坑竖井的变形控制要求较高,将其支护方案设计为“钢格栅+钢筋网片+喷射混凝土+阻水注浆”;同时,经变形预测,得到基坑竖井后期变形增加速率较小,变形趋于稳定,且预测值均小于变形控制值,说明基坑竖井的支护设计合理有效,为类似工程积累了经验。

To ensure the construction safety of the foundation pit shaft,this article combines the results of the shaft survey,and based on its support design,further combines the results of on-site deformation monitoring to evaluate its support effect through deformation prediction.The analysis results indicate that the deformation control requirements for the vertical shaft of the foundation pit are relatively high.The support scheme is designed as"steel grid+steel mesh+sprayed concrete+water blocking grouting";Meanwhile,through deformation prediction,the rate of increase in the later stage of the foundation pit shaft is relatively small,and the deformation tends to stabilize.The predicted values are all smaller than the deformation control values,indicating that the support design of the foundation pit shaft is reasonable and effective,accumulating experience for similar projects.