依托济南市济泺路穿黄隧道东线工程,选取1130组掘进数据,按照施工顺序划分数据集,采用粗细程度、软硬程度、密实程度和渗透能力4个维度描述土体的物理力学状态,分别建立基于长短期记忆模型(Long-Short Term Memory,LSTM)、随机森林模型(...依托济南市济泺路穿黄隧道东线工程,选取1130组掘进数据,按照施工顺序划分数据集,采用粗细程度、软硬程度、密实程度和渗透能力4个维度描述土体的物理力学状态,分别建立基于长短期记忆模型(Long-Short Term Memory,LSTM)、随机森林模型(Random Forest)和BP神经网络的盾构隧道掘进参数预测模型,详细对比分析3种模型对总推力和掘进速度的预测效果。研究表明:(1)LSTM模型在按施工顺序预测盾构总推力和掘进速度时,平均相对误差仅为3.72%和7.41%,模型训练时间均在20 s以内,整体表现优于随机森林模型和BP神经网络;(2)在地形发生剧烈变化以及盾构掘进线路在直线与平曲线过渡时,总推力和掘进速度出现较大波动,LSTM模型预测结果相对误差偏大的组数仅占4%与10.2%,且总体误差满足施工要求;(3)随机森林模型预测结果的相对误差在总推力和掘进速度剧烈波动的环段处偏大,数量偏多,因此在按施工顺序预测时不是优选。展开更多
Since 2000, the French National Radioactive Waste Management Agency （ANDRA） has been constructing an Underground Research Laboratory （URL） at Bure （east of the Paris Basin） to perform experiments in order to obt...Since 2000, the French National Radioactive Waste Management Agency （ANDRA） has been constructing an Underground Research Laboratory （URL） at Bure （east of the Paris Basin） to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical （HM） behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional （mode I） and shear fractures （modes II and III） induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts.展开更多
文摘依托济南市济泺路穿黄隧道东线工程,选取1130组掘进数据,按照施工顺序划分数据集,采用粗细程度、软硬程度、密实程度和渗透能力4个维度描述土体的物理力学状态,分别建立基于长短期记忆模型(Long-Short Term Memory,LSTM)、随机森林模型(Random Forest)和BP神经网络的盾构隧道掘进参数预测模型,详细对比分析3种模型对总推力和掘进速度的预测效果。研究表明:(1)LSTM模型在按施工顺序预测盾构总推力和掘进速度时,平均相对误差仅为3.72%和7.41%,模型训练时间均在20 s以内,整体表现优于随机森林模型和BP神经网络;(2)在地形发生剧烈变化以及盾构掘进线路在直线与平曲线过渡时,总推力和掘进速度出现较大波动,LSTM模型预测结果相对误差偏大的组数仅占4%与10.2%,且总体误差满足施工要求;(3)随机森林模型预测结果的相对误差在总推力和掘进速度剧烈波动的环段处偏大,数量偏多,因此在按施工顺序预测时不是优选。
文摘Since 2000, the French National Radioactive Waste Management Agency （ANDRA） has been constructing an Underground Research Laboratory （URL） at Bure （east of the Paris Basin） to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical （HM） behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional （mode I） and shear fractures （modes II and III） induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts.
