A cement-based method for fixing sand in laboratory channels

Abstract

A method to fix movable beds in river-related laboratory research or physical model studies is proposed and investigated. The motivation was to develop a method that would: (1) not involve the use of harsh chemicals and (2) ensure that the granular roughness of the original movable bed was maintained. The method involves coating the surface with a mixture of sand and Portland cement. Laboratory tests were conducted to determine the amount of cement, and investigate the best method of application, effect on roughness, shear strength and durability. It is found that the method can be used to fix both flat and deformed beds. The method is particularly effective for sands up to 1.1 mm, when it is possible to ensure that the granular roughness of the fixed bed is comparable to that of the movable bed by merely using in the coating mixture a coarser sand than the original one.

Keywords:

• Bed roughness
• durability
• fixed bed
• hardening
• movable bed
• sand–cement mixture
• shear strength

Acknowledgements

This research was supported by funds from the Natural Sciences and Engineering Research Council of Canada through a Discovery Grant to the second author. The authors are grateful to three anonymous reviewers, the Associate Editor and the Editor, for their valuable comments and suggestions, which were of great help to develop this paper to its present form.