Personal 8-h shift exposure to respirable dust, diesel engine exhaust emissions (DEEE) (as respirable elemental carbon), and respirable crystalline silica of workers involved in constructing an underground metro railway tunnel was assessed. Black carbon (BC) concentrations were also assessed using a MicroAeth AE51. During sprayed concrete lining (SCL) activities in the tunnel, the geometric mea...

Tunnel Boring Machines (TBMs) are used for tunneling and underground construction, by excavating material subsequently installing a segmental concrete tunnel liner support. However, unknown ground conditions pose significant risk to operations any damage the machine can be disastrous project. There is need tools which look ahead of TBM potential hazards during tunneling, such as water saturated...

The construction of tunnels in densely populated urban areas poses a significant challenge terms anticipating the settlement that may result from tunnel excavation. This paper presents new and more realistic modeling method for excavation using Tunnel Boring Machine (TBM). is compared with other reference methods validated model subsurface excavated by TBM slurry shield. A parametric study cond...

Introduction: The application of intelligent learning methods to the mining characteristics and rules time-series data has gained increasing attention with rapid development deep learning. One critical such is assistant driving tunnel boring machines (TBMs), for which optimization parameters essential improve construction efficiency. However, existing prediction models TBM are “static” cannot d...

The  tunnel  boring  machine  (TBM)  penetration  rate  estimation  is  one  of  the  crucial  and complex  tasks  encountered  frequently  to  excavate  the  mechanical  tunnels.  Estimating  the machine  penetration  rate  may  reduce  the  risks  related  to  high  capital  costs  typical  for excavation  operation.  Thus  establishing  a  relationship  between  rock  properties  and  TBM pe...

Abstract Tunnel boring machine (TBM) operational data is mostly analysed with respect to that was recorded during the advance of TBM. Focusing on standstills a gripper TBM, we analyse rock loads were passively in cylinders small roof support shield. These are situated beneath TBM’s shield – extending it against mass non-advance periods. Equipped pressure sensors, they enable unique opportunity ...

Practical Tunnel-boring Machine (TBM) guidance systems usually use sophisticated instruments to obtain the orientation of the TBM. These systems require frequent calibration and work shutdown, making the procedure complex and time consuming. Besides, the majority of current TBM guidance solutions cannot provide the position of the invisible cutter head analytically including commonly used laser...

Tunnel excavation is prone to segment cracks, which may lead serious safety accidents. This work aims investigate the type, location and occurrence time of cracks in a large-diameter underwater shield tunnel also ascertain causes cracks. The correlations between crack characteristics tunneling parameters were analyzed. effect jack deflection poor assembly on investigated using refined finite el...