Grant: Collaborative Research and Development Grants

This proposed research is to extend a successful NSERC Engage research project into a thorough investigation of applying the deep mixing method (DMM) for ground improvement of sensitive Champlain Sea clay. Infrastructure development around the Ottawa region and the Upper St. Lawrence River region is important for Canada's economy; however, the local marine clay known as Champlain Sea clay makes construction activity difficult due to its sensitive nature. Champlain Sea clay has also been responsible for many landslides in the area. Therefore, a novel ground improvement method is urgently required for safe and cost-efficient infrastructure development. DMM is a ground improvement technique where a binder such as cement or lime is mixed in-situ into the soil to improve its properties and make construction workable. Since its inception in the 1970s, DMM has become very popular in many parts of world, including Western Canada. However, DMM has yet to be applied in Eastern Canada due to a lack of test data. During a previous NSERC Engage project, the efficiency of stabilizing Champlain Sea clay with cement was confirmed with a significant strength increase and compressibility reduction. The objectives of this research are to 1) obtain the right binder and optimum dosage and thoroughly investigate the geotechnical properties of stabilized Champlain Sea clay; 2) test the long-term performance of DMM stabilized Champlain Sea clay; and 3) develop a rigorous design method. The introduction of DMM could have significant economic and social benefits for infrastructure development in Eastern Canada.