Tensile Strengths and Size Effects of Biocemented Sands

Biocementation has broad application prospects for reinforcing granular materials in geotechnical engineering. However, only few studies have been conducted on the size effect in biocemented granular materials, despite the recognition of the size effect in the uncemented ones. In this study, a series of tests on Brazilian tensile strengths were carried out for biocemented sand, focusing on the size effect. Glass bead sand (GBS) and calcareous sand (CCS) of five different particle sizes were adopted at two different biocementation levels. Under otherwise identical conditions, the tensile strengths of biocemented CCS specimens were higher than that of the biocemented GBS specimens. The tensile strengths of the biocemented specimens decreased with an increase in particle size, which can be captured by a power function, inspired by the size-effect relation. The novel findings of this study can provide the size-effect function for the establishment of constitutive models and the data basis for the validation of numerical models when theoretical models are necessary in predictions of deformation and failure for field-scale biotreated soils.