Modelling of three-phase strength development of ordinary Portland cement- and Portland blast-furnace cement-stabilised clay

摘要

Estimating the strength development of cement-stabilised clay is imperative for quality control and ascertaining satisfactory achievement of the required performance in construction. Most of the strength prediction models adopt either a hyperbolic or logarithmic model to represent the strength-time relationship. However, these models generally consider only a certain range of curing ages, offering inaccurate estimates at very early or late age phases. Moreover, the application of cement-treated clay to land reclamation often requires a small cement dosage and high water content, which differs from the conventional onshore soil improvement work. In this paper, the database of strength development of cement-treated clay at high water content and low cement dosage is expanded, and the strength development of various types of cement-treated clay over a wide range of curing time (age) is discussed. A three-phase strength development behaviour is observed. In view of the limitation of the existing models, the cumulative distribution function of the log-normal distribution is introduced to represent the complete three-phase strength development, including the early-age strength as well as the final ultimate strength. Matching estimates of the strength development over a wide range of clays and cements are observed, as presented in this paper.