Influence of placement method on the in situ density of hydraulic sand fills

• Published in: Canadian Geotechnical Journal
• Main Authors: Sladen, J. A., Hewitt, K. J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1989
• Subjects: Civil and Structural Engineering; Geotechnical Engineering and Engineering Geology; Beaufort Sea
• Online Access: http://dx.doi.org/10.1139/t89-058; http://www.nrcresearchpress.com/doi/pdf/10.1139/t89-058

The range of densities achievable by hydraulic placement of sand straddles the boundary between values giving acceptable potential performance and those giving unacceptable potential performance. This has led to concerns over the safety of structures using hydraulic fills, such as the artificial drilling islands in the Canadian Beaufort Sea. Liquefaction failures of hydraulically placed sand have occurred at four or more of these islands. Until recently, the factors affecting in situ density were little understood. Data obtained from several artificial islands are presented and these are used to demonstrate the overwhelming influence of method of placement on in situ density. The possible reasons for this influence and the implications for design are discussed. Recommendations are made for research that, together with conclusions drawn in the paper, should allow hydraulic fills to be used with more confidence in the future. Key words: sand, hydraulic fill, liquefaction, cone penetration test.