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A platform for research: civil engineering, architecture and urbanism
A study on the pressure-holding mechanized shield machines
A new pressure-holding mechanized shield machine has been developed and put into operation. This new shield machine is able to hold the collapsing pressure of the cutting face, thereby causing the sand plug to be nearly impermeable. The soil which is released by stress during excavation is compacted in the screw discharger, part of the mucking equipment, to form the sand plug. This paper describes an outline comparing machine types, principles of sand plug formation and pressure holding performance, and includes experimental test results. Employment of a pressure-holding mechanized shield machine with a screw discharger has the following advantages: This excavation method has little influence on the natural ground conditions as the stressreleased soil is made into a close-to-natural type of soil and the pressure is held by sand plugs which are formed with the excavated soil in the screw discharger. A reasonable way of soil discharge and a cutting face held by well pressure can be obtained by discharging the soil streight along the screw shaft. In spite of the simple structure, the machine can be widely used under a variety of soil condition. This method can be applied for use in soft, highly liquid strata by adopting a volumetric discharger on the screw discharger outlet and maintaining earth pressure through control of the amount of discharge. (Wassmann)
A study on the pressure-holding mechanized shield machines
A new pressure-holding mechanized shield machine has been developed and put into operation. This new shield machine is able to hold the collapsing pressure of the cutting face, thereby causing the sand plug to be nearly impermeable. The soil which is released by stress during excavation is compacted in the screw discharger, part of the mucking equipment, to form the sand plug. This paper describes an outline comparing machine types, principles of sand plug formation and pressure holding performance, and includes experimental test results. Employment of a pressure-holding mechanized shield machine with a screw discharger has the following advantages: This excavation method has little influence on the natural ground conditions as the stressreleased soil is made into a close-to-natural type of soil and the pressure is held by sand plugs which are formed with the excavated soil in the screw discharger. A reasonable way of soil discharge and a cutting face held by well pressure can be obtained by discharging the soil streight along the screw shaft. In spite of the simple structure, the machine can be widely used under a variety of soil condition. This method can be applied for use in soft, highly liquid strata by adopting a volumetric discharger on the screw discharger outlet and maintaining earth pressure through control of the amount of discharge. (Wassmann)
A study on the pressure-holding mechanized shield machines
Eine Studie ueber druckhaltende mechanisierte Tunnelvortriebsmaschinen
Yoshikawa, T. (author)
Hitachi Zosen. Technical Review ; 39 ; 33-40
1979
8 Seiten, 15 Bilder, 4 Tabellen, 10 Quellen
Article (Journal)
Japanese
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