Abstract
High-range water reducers, such as superplasticisers, can be potentially viable for cement grouting applications. In this study, we investigate the influence of two types of superplasticisers-one based on polycarboxylate ether and another based on naphthalene condensates-on the injectability of thick cement grouts into coarse soil and on the shear strength parameters of the grouted soil. Injectability tests were performed on soil columns with various superplasticiser dosages and grouts prepared with different water-to-cement ratios over a wide range of grouting pressures. The shear strength parameters of the grouted soil were evaluated through undrained unconsolidated triaxial compression tests.