Depth of penetration of lubricant fluids and water in Queenston shale of southern Ontario

Abstract

Queenston shale is a rock formation located in southern Ontario in Canada that exhibits time-dependent deformation behaviour induced by water penetration. Microtunnelling is an efficient technique that can be used to construct pipelines and tunnels in Queenston shale. In this technique, lubricant fluids, such as bentonite solution and polymer solution, are utilized, which can have a significant impact on the time-dependant deformation (i.e., swelling) of Queenston shale within their depth of influence. A test procedure was developed in this research to investigate the depth of penetration of lubricant fluids and water in Queenston shale. These fluids were applied under pressure, similar to that used in the microtunnelling process, on Queeenston shale specimens. The depth of penetration of these fluids into the test specimens was monitored with time. It was concluded that the penetration depth varied for the various fluids considered. Water had the deepest penetration into Queenston shale. Based on the observed results, an equation is developed to predict the depth of penetration of various fluids in the Queenston shale mass. Results of this research can assist in evaluating the depth of influence of various fluids in Queenston shale and the associated swelling zone can be predicted.