砂黏复合地层盾构掘进参数变化规律及掘进速率预测研究

为研究砂黏复合地层中复合比与盾构掘进参数之间的规律，依托石家庄地铁1号线白留区间隧道工程，基于现场盾构掘进试验，通过对盾构原始掘进参数的二次转换，建立标准推力-标准转矩特征空间，并对传统盾构掘进速率模型进行修正。研究结果表明： 1）正常掘进状态下，标准推力和标准转矩成对数关系，随着复合比的降低，标准推力和标准转矩增加； 2）根据参数点在特征平面的分布和对应的施工状态，将特征平面划分为Ⅰ区(正常掘进区)、Ⅱ区(转矩偏大区)和Ⅲ区(推力偏大区)，并依据复合比的不同，将正常掘进区进一步划分为Ⅰ1、Ⅰ2、Ⅰ3、Ⅰ4区； 3）基于标准推力和标准转矩，建立适用于砂黏复合地层的掘进速率预测模型。

Tunneling Parameters Variation Laws and Velocity Prediction of Shield Tunneling in Sandy clay Composite Strata

The variation laws of composite ratio of sandy clay composite strata with tunneling parameters of shield in Bailiu Section tunnel project of Shijiazhuang Metro Line 1 are studied. Based on the site shield tunnel test, the standard thrust standard torque characteristic space is established by the secondary conversion of the original tunneling parameters of shield, and the traditional shield tunneling velocity model is modified. The results show that: (1) Under the normal tunneling condition, there is a logarithmic relationship between standard thrust and standard torque; with the decrease of composite ratio, standard thrust and standard torque increase. (2) According to the distribution of parameter points in the characteristic plane and corresponding construction state, the characteristic plane is divided into zoneⅠ (normal tunneling zone), zone Ⅱ (excessive torque zone) and zone Ⅲ (excessive thrust zone); and according to the different composite ratios, the normal tunneling zone is further divided into zoneⅠ1 , Ⅰ2 , Ⅰ3 and Ⅰ4 . (3) Based on the standard thrust and standard torque, a prediction model of tunneling velocity for sandy clay composite strata is established.