Study of the Permeability of Foam Conditioned Soils with Laboratory Tests
Open Access
- 1 April 2010
- journal article
- Published by Science Publications in American Journal of Environmental Sciences
- Vol. 6 (4), 365-370
- https://doi.org/10.3844/ajessp.2010.365.370
Abstract
EPB tunneling requires that the excavated soil has a plastic and pulpy behavior to be able to apply a stabilizing pressure to the face, but it should also be impervious to counteract filtration forces that could develop ahead of the face. The evaluation of this parameter in granular soil, before and after conditioning, is therefore of key importance for a correct conditioning agents choice. Approach: A new laboratory procedure for testing the permeability of conditioned soil with foam has been proposed. The tests have been carried out at different hydraulic loads, chosen to be 0.1 bars and 1 bar. Results: The proposed procedure has been applied to determine the behavior of differently conditioned granular soils: a fluvial sand and a pozzolanic soil and has shown that an increasing of the FIR induces a relative increase in the time required by water to pass through a standard sample, emphasizing, in this way, the effectiveness of the conditioning on impermeability of the soil. Conclusion: The tests have shown the laboratory procedure adequately captures the behavior of the conditioned soil. Further, the proposed test may also be used as an index for the preliminary definition of the quality of the soil conditioning and suitability for EPB tunnelinKeywords
This publication has 8 references indexed in Scilit:
- Using the Slump Test to Assess the Behavior of Conditioned Soil for EPB TunnelingEnvironmental & Engineering Geoscience, 2009
- The Tunnel Boring Machine Advancements in Horizontal and Up-Hill TunnelsAmerican Journal of Applied Sciences, 2009
- Analysis of the Tunnel Boring Machine Advancement on the Bologna-Florence Railway LinkAmerican Journal of Engineering and Applied Sciences, 2009
- Soil conditioning of sand for EPB applications: A laboratory researchTunnelling and Underground Space Technology, 2008
- Screw Conveyor Device for Laboratory Tests on Conditioned Soil for EPB Tunneling OperationsJournal of Geotechnical and Geoenvironmental Engineering, 2007
- Mechanics of tunnelling machine screw conveyors: model testsGéotechnique, 2006
- Use of chemical foam for improvements in drilling by earth-pressure balanced shields in granular soilsTunnelling and Underground Space Technology, 1998
- Face stability conditions with earth-pressure-balanced shieldsTunnelling and Underground Space Technology, 1996