Stability Evaluation Of N-Sodium Silicate Chemical Grouts by Means of Rheology and Syneresis Testing-Video

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Video Summary

The presentation examined sodium silicate grout gelation and syneresis using rheological and permeation tests. Conventional methods, such as the tilt-cup test and rotational viscometry, identify gelation only after the grout has begun changing. Oscillatory rheometry detected this transition earlier: the phase angle began falling from liquid-like behavior while the measured modulus remained very low. This could help determine when to start or stop grouting in the field.<br /><br />For syneresis, grout-permeated sand specimens were monitored for water loss. Normalizing loss by specimen surface area—not total mass or volume—best aligned results across different specimen sizes. Water loss was faster initially, then slowed, and repeatedly opening and rewrapping specimens introduced measurement bias.<br /><br />The speaker concluded that traditional tests remain useful for quality control but are limited for design. Syneresis should be measured in grouted soil, not just grout alone, and further work is needed to translate laboratory findings to field-scale grouting.

Keywords

sodium silicate grout

gelation

syneresis

oscillatory rheometry

grouting