兰州砂卵石地层盾构施工的peck公式参数优化

Parameter optimization of peck formula for shield construction in Lanzhou sand pebble ground

针对peck经验公式预测隧道开挖引起的地表沉降受地质环境、开挖方式等影响的问题,揭示隧道开挖引起地表沉降的一般规律。基于兰州砂卵石地层某地铁盾构区间,取30个典型断面地表沉降的监测数据,利用线性回归方法,引入地表最大沉降量的修正系数α和沉降槽宽度修正系数β,修正优化peck公式。研究结果表明:在兰州砂卵石的地层条件下,当α∈[0.5139,0.9364],β∈[0.5987,0.7609]时,优化后的peck曲线与监测数据较为吻合。研究结论为城市相似地层下地铁建设提供参考和依据。

According to the peck empirical formula,the problem of surface settlement caused by tunnel excavation is affected by geological environment and excavation method.The general law of surface settlement caused by tunnel excavation is revealed based on a subway shield section of the Lanzhou sand-pebble stratum.The monitoring data of 30 typical sections are taken by using the linear regression method.The correction coefficientαof the maximum settlement of the surface and the correction coefficient of the settlement tank widthβare introduced with a modified and optimized formula.The data show that under the stratum conditions of Lanzhou sand pebble,whenα∈[0.5139,0.9364],β∈[0.5987,0.7609],the optimized peck curve is in good agreement with the monitoring data.The research results provide a future reference and basis for subway construction under similar stratum in cities.