【摘要】 在针对基坑开挖对下卧既有隧道影响的预测方法中,常规解析计算方法仅考虑了开挖卸载对下卧隧道的影响,忽略了基坑降水因素的作用,必将使其预测结果存在一定误差。提出一种新的计算方法,该方法基于附加荷载两阶段法,结合土的有效应力原理,Mindlin解和Pasternak双参数地基模型,初步探讨了包含基坑降水因素影响的基坑施工对其下卧既有隧道的影响,并分析了降水因素在整个影响过程中的作用。最后以深圳车公庙枢纽工程西风道基坑为案例,将计算结果与既有隧道变形监测数据对比,验证了本文计算方法的有效性。更多还原

【Abstract】 In the methods of predition of the effect of foundation pit excavation on underlying tunnel, the conventional analytical calculation method only considers the effects of excavation unloading on the underlying tunnel, ignoring the role of foundation pit dewatering factors, which will inevitably make errors in the prediction results. A new calculation method was proposed in this paper. Based on two-stage additional load method, combined with soil effective stress principle, Mindlin solution and two-parameter Pasternak foundation model, the method studied the foundation pit excavation effect on the underlying existing tunnel considering the influence of dewatering factor, and analyzed the role of dewatering in the whole process of influence. Finally, the calculation results were compared with the existing tunnel deformation monitoring data in the case of the west ventilation pavilion of Che Kung Temple Shenzhen project and verified the validity of the calculation method.更多还原