苏州桥站中桩中柱施工工艺参数监测及分析

在地铁隧道建设过程中,暗挖车站洞内机械成桩技术因其降水周期短、施工安全性高、绿色节能性好等优势具有较强推广意义。结合北京地铁12号苏州桥站中桩中柱机械成桩施工的基本情况,对中桩中柱施工参数、资源使用量和工艺流程进行了监测和分析,根据地层环境调整钻进速度可以缩短成桩施工周期,增加地层⑥与地层⑧钻进速度至2 m/h可以减少中桩的成孔用时,增加地层⑦与地层⑨的水资源用量可加强泥浆对桩孔的护壁效果;根据工程数据建立了机械成孔工况预测人工神经网络模型,利用该模型对4根桩的施工情况进行预测,预测结果与监测参数的绝对误差大于5%为工况异常;提高钢管柱调平及灌注效率可以缩短施工周期,改善中桩中柱质量。根据中桩中柱施工工艺参数进行监测及分析为类似工程施工提供借鉴。

Monitoring and Analysis of Construct Process Parameters of Middle Piles at the Suzhouqiao Station

In the process of subway tunnel construction,promoting the mechanical pile construction technology is of great pragmatic significance,due to its short precipitation period,high construction safety and green energy saving.In this paper,combined with the construction situation of middle piles and middle columns at the Suzhouqiao station of Beijing metro line 12,the construction parameters,resource usage and construction process of middle stakes are monitored and analyzed.Improving drilling speed can shorten the piling construction period according to the stratum situation.Adjusting drilling speed to 2 m/h can reduce the drilling time in stratum 6 and 8.Increasing the water resource usage in stratum 7 and 9 can strengthen the mud protective effect to pile hole.The Artificial Neural Network model was established with engineering data to predict the mechanical drilling condition.This model was used to predict the construction conditions of four middle piles.If the absolute error between the prediction result and the monitoring parameter is more than 5%,the working condition is abnormal.The construction period can be shortened by improving the efficiency of adjusting column pipe verticality and pouring the concrete,while improving the quality of the middle pile.Based on the monitoring and analysis of the construction process parameters of middle piles and middle columns,this research provides reference for similar engineering constructions.