Sustainability Considerations For Ground Improvement Technique Using Controlled Modulus Columns

H. H. Nguyen, H. Khabbaz, B. Fatahi, P. Vincent and M. Marix-Evans

Sustainability is becoming an ever more important consideration for the selection of ground improvement methods on construction projects around the world. When considering this criterion, the controlled modulus column (CMC) technology emerges as one of the relatively novel technologies that are capable to deliver valuable and sustainable outcomes. CMC installation is a vibration free process and produces very limited soil cuttings, making CMC suitable for improvement of soft ground, contaminated sites and ones adjacent to sensitive structures. Besides, CMC uses grout only without the use of steel reinforcement; hence carbon footprint estimated for CMC is generally lower than those for traditional piling techniques. Besides these valuable aspects, it is believed that this technology can still be advanced to contribute more to the sustainable development, owing to ongoing research works and practical experience. This paper summarises the key sustainability aspects of using CMC technology and highlights some potential aspects for further development. Future research directions are discussed to enhance sustainable design practice. These include general discussions on the issues of economic design with trial field tests, the use of recycled industrial by-products for grout mix, improved design, maximising the resiliency of structures and the energy consumption. The CMC installation effects on the surrounding soils and environment are also discussed sensibly in this paper.