Polymer Emulsion Grouting for Water Cutoff in Tunnel Structures
Paul M. Gancarz, P.E., M.ASCE,1 John E. Minturn,2
Nico J. Grobler3, and Deon Van Dyk4
1Lead Grouting Engineer – Northeast USA, Sovereign-Thyssen L.P., New York, NY USA;
email: pgancarz@sovereign-thyssen.com
2General Manager, Sovereign-Thyssen L.P., New York, NY USA;
email: jminturn@sovereign-thyssen.com
3Vice President, Sovereign International Inc., New York, NY USA;
email: ngrobler@sovereignhydro.com
4Lead Hydrologist, Sovereign International Inc., New York, NY USA;
email: dvd@sovhyd.com
ABSTRACT
Seepage in underground structures is a common problem facing contractors and facility owners alike. Unwanted groundwater intrusion – which arises as a consequence of initial construction – can develop into a costly repair and a prolonged tunnel maintenance program. The objective of this study is to illustrate the technology, performance and material characteristics of polymer emulsion and how it has been successfully applied to the problem of tunnel facility leakage. A regular grid of grout holes are drilled through the tunnel’s structural lining and polymer emulsion is pressure grouted into the annulus. The result is the formation of a dense, flexible barrier along the exterior of the underground structure which prevents water from entering the facility. Curtain grouting with polymer emulsion has been used in tunnel structures to provide a cost-effective solution for tunnel leakage with minimal impact to project schedules.
INTRODUCTION
Groundwater entry into facilities located near or below the groundwater table places significant burden on both contractors and owners. Pumping and treatment cost, protecting sensitive
equipment, service delays and maintaining public spaces can be considerable. It is therefore important, given the significant impact on cost over the tunnel’s lifetime, that fully investigating, monitoring and preventing groundwater infiltration is done early in the construction cycle.
Leakage often occurs as the result of deficiencies in the initial waterproofing system. Initial waterproofing for underground structures typically consist of PVC or HDPE sheet membranes, which are installed in a grid-like fashion between the initial and final structural lining systems. Sheets are usually either welded together with a hot-air element, or bonded...
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