Single model establishing strength of dispersive clay treated with distinct binders

Dispersive clays experience deflocculation in the presence of somewhat clean still water and are extremely vulnerable to erosion. Lime or Portland cement usage is one of the most applied methods to amend such adverse characteristics and enhance mechanical properties. Present research is aimed at a single power function quantifying the effect of amounts of binder, porosity, and curing period in the assessment of unconfined compressive strength (q(u)) of dispersive clay-binder mixtures. Analysing q(u) results, it was found that a ratio between porosity and binder volumetric content controls the strength of blends. The q(u) values of the specimens moulded for each binder type were also normalized (i.e., divided by the q(u) attained at a specific porosity/ binder ratio) reaching a single power function quantifying the influence of the binder's amount, porosity, and curing time. From a pragmatic standpoint, this denotes that carrying out only one unconfined compression test with a specimen moulded with a specific binder, porosity, and cured for a given time period allows to determine an equation that controls the strength for a whole range of porosities and binder contents. The developed normalization was successfully extended to other fine-grained soils treated with cement, lime, and even pozzolan-lime, considering longer curing periods.