2024 Volume 80 Issue 1 Article ID: 23-00132
The authors developed a new liquefaction countermeasure method that can increase liquefaction resistance by increasing the density of liquefiable ground through an injection with leaf vein shape grout. We also confirmed its effectiveness by conducting executive tests in a large size pit, shake tablet tests and so on. This paper presents the results of the injection tests of the proposed method applied to the natural ground. The test results indicated that the proposed method could be carried out with a small amount of a ground uplift. In addition, it was confirmed that sufficient improvement effects could be achieved through soil investigations, such as piezoelectric drive cone tests, density logging and pressure meter tests conducted before and after the injection. Furthermore, the improvement effect for the ground with high fine-grain content could be reasonably evaluated by using density logging or pressure meter tests, although a N value inspection might underestimate the effect. Finally, some soil investigations were conducted at the same site after two years later to check the sustainability of the improvement effect. The results showed that the improvement effect was maintained at a sufficient level.
