Comparison of rheological models for jet grout cement mixtures with various stabilizers

The use of jet grouting technique for ground improvement has become very popular approach for civil engineering projects. Despite the availability of large number research related to development of this technique, the rheological models of grout flow have still become in concern for jet grout applications. Thus, an investigation on the performances of the most common rheological models (Bingham, Modified Bingham, Casson, Herschel-Bulkley, Robertson-Stiff, De Kee) for prediction of flow behavior in terms of the shear stresses due to the cement grout mixtures incorporating with the stabilizers of clay, sand, lime, bottom ash in various proportions (0-100%) has been addressed in this article for jet grouting. For this purpose, a thorough comparison of the rheological models has been performed using the flow curves of the shear stress-shear rate data collected from previous study. On the basis of the comparisons, the performance have been presented in a ranking scheme that represents the favorable models within the low to high ranking. It is found from the performances that all rheological models, except the Casson, at most of the stabilizer inclusions have been adequately fitted to the shear stress-shear rate data, resulting in the lower errors (MAE, RMSE) and the strong correlations (R>0.8) with a significant evidence (p<0.05). It is proposed from the ranking scheme that the Robertson-Stiff model and derived formulas in this study are most acceptable (high ranking), the De Kee model is moderate acceptable (moderate ranking), the Herschel-Bulkley and Modified Bingham models are less to moderate acceptable (low to moderate ranking), the Bingham model is least acceptable (low ranking), and the Casson model is unacceptable. Applicability of the ranking performances is relatively promising for jet grouting when compared with the measured shear stress-shear rate data. (C) 2016 Elsevier Ltd. All rights reserved.