Shear strength of the Tiller-Flotten peat stabilised with different levels of cement and biochar after 28 days of curing. Vertical bars indicate standard errors of the means (n = 3). For each stabilised soil, bars with the same letter(s) within each cement quantity level are not significantly different according to Welch's t-test at P < 0.05. A full-colour version of this figure can be found on the ICE Virtual Library (www.icevirtuallibrary.com)