Comment on Determination of soilwater characteristic curve variables by Qian Zhai and Harianto Rahardjo [Comput. Geotech. 42 (2012) 3743]
The determination of soilwater characteristic curve variables, proposed by [1] provides more flexibility compared to conventional methods such as [4]. However, if the method A described by the authors is used, the air-entry and residual suctions would be difficult to compute, because the parameters m and n depend directly on the residual suction and vice versa, which leads to more unknowns than equations. It should be noted that the parameters of the original formula of [2] composed of the correction factor, are calculated in semi-log plot by using the neperian logarithm and not with the decimal logarithm.
soilwater characteristic curve residual suction parameters air-entry suction