复合地层盾构掘进参数相关性分析及掘进速度预测

掘进速度预测对于提高复合地层盾构掘进施工效率具有重要作用。本文依托南京轨道交通工程复合地层区段现场盾构掘进数据,在盾构区间地层分区的基础上对主要掘进参数进行研究,分析各掘进参数与掘进速度之间的相关性。结果表明:地层越硬,刀盘转速、扭矩、推力均越大,土仓压力越小,软硬不均复合地层刀盘扭矩明显偏大;在复合地层中仍存在掘进速度与贯入度、螺旋输送机转速成正比关系,但掘进速度越大,刀盘扭矩和推力不一定越大。在复合地层中引入硬岩复合比作为回归参数,采用多元线性回归建立掘进速度预测模型,将相同区段预测掘进速度与实际掘进速度进行对比,以验证模型的的准确性和可信度。本文分析方法可为复合地层掘进施工提供指导。

Correlation Analysis of TBM Tunneling Parameters and Prediction of Tunneling Speed in Mixed Ground

Prediction of tunneling speed plays a key role in improving the construction efficiency of shield tunneling in mixed ground.Taking the shield tunneling in mixed ground of Nanjing rail transit project for example,based on the stratification of shield tunneling interval,the main tunneling parameters are studied and the correlation between each tunneling parameter and tunneling speed is analyzed.The results show that the greater speed,torque and thrust of the cutter head and the smaller chamber earth pressure will show in the harder ground;significantly larger cutter head torque appears in the mixed ground.In the mixed ground,the tunneling speed is proportional to the penetration and the speed of screw conveyor,while the torque and thrust of the cutter head are not necessarily for a larger tunneling speed.A multivariate linear prediction model of tunneling speed is established considering face composition.The predicted and actual results are compared to confirm the accuracy and credibility of the model.It is found that the proposed method in the paper can provide guidance for the construction of tunneling in mixed ground.