Evaluating Liquefaction Strength Prediction Method for Low Improvement Ground Materials

A limit exists to what can be captured by extending the current liquefaction strength evaluation methods in the case of a massive earthquake such as the Great East Japan Earthquake. Therefore, developing new technologies for predicting and countermeasures against liquefaction damage based on instead of new concepts is essential. One of the current liquefaction prediction methods is the FL method. This method requires liquefaction strength determined by an undrained cyclic triaxial test. However, environmentally friendly low-modification liquefaction countermeasures with low cement addition, such as the premixing treatment method, are primarily used in reclaimed port areas, and cement is commonly used in ground improvement methods. However, it is challenging to determine the liquefaction strength of ground materials that have been improved and solidified over time, due to the loading capacity of a typical undrained cyclic triaxial test apparatus. Therefore, Koga et al. (Abstracts of Master’s Thesis, Chuo University, pp 1–4 (2013)) investigated a method of determining the liquefaction strength of low-improved ground materials using the cone index test, a simple method of measuring liquefaction strength. This paper reports the results of a study on a prediction method to determine the strength of sandy materials with different grain sizes after cementation and stability based on the liquefaction strength of low-mixing and early-age materials.