| 摘要 |
PURPOSE:To grasp definitely the properties of earth and sand filled up and pressurized in a cutter chamber during shielding operation, carry out proper shield control and build transverse pits swiftly during earth pressure shield excavation in any natural ground. CONSTITUTION:A bulkhead 12 is installed to the front of a shield cylinder where a cutter chamber 6 is installed by way of this bulkhead. To the front of the cutter chamber is installed a drill 3. An earth discharge device 8 is connected to the rear side of the cutter chamber. In a shield machine designed as described above, a density/humidity measuring instrument 21a which measures the density and or the moisture content, is installed to the bulkhead and or an excavator or the like by using a radio isotope(RI) and directly measures the density and or the humidity content of the earth and sand in the cutter chamber. This detected value helps an operator to estimate and grasp the properties of the earth and sand so that stabilized excavation may be carried out by controlling the above measurement. |
