Ditapis dengan
The tunnelling system for the British section of the Channel tunnel phase II …
A 260 m length of the British end of the service tunnel for the Channel tunnel was driven over a period of two and a half months early in 1975. The operation of the tunnelling machine was observed as it advanced through the Lower Chalk and is described in terms of its principal operations, namely cutting, steering, spoil removal and lining. In addition to the normal operation of tunnelling, exp…
Site investigation for tunnelling trials in chalk
A site investigation was carried out prior to the tunnelling trials in order to select the best tunnel alignment, predict chalk conditions along this alingment and evaluate the site investigation procedure used. The site investigation consisted of several phases; preliminary investigations, a two stage borehole investigation and measurements made in a 3m diameter shaft. In addition, chalk quali…
Tunnelling trials in chalk: rock cutting experiments
This report presents the results of the performance of arrangments of drag picks and disc cutters cutting through lower chalk during the tunnelling trials at Chinnor, Oxfordshire. Power changes produced by varying the cutter tool type and arrangement on the machine head were recorded and plotted against cutter tool and machine variables. The depth of cut and cutting to relief were fiound to be …
The effects of ground vibration during bentonite shield tunnelling at Warrington
The maximum measured ground vibration (expressed in terms of resultant peak particle velocity) was 3.9 mm/s. The vibration was characterised by random high velocity particle motions resulting from impacts between the machine's disc cutters and glacial boulders in the tunnel face. Surface and subsurface settlement measurements were made along the tunnel line. Laboratory tests and other field dat…
