A Simplified Method for Estimation of Horizontal Consolidation Coefficient from Self-Boring Pressuremeter Test

The self-boring pressuremeter test (SBPT) has proven effective in determining geotechnical properties in situ with minimal disturbance. Among the parameters obtained from SBPT, the horizontal coefficient of consolidation (ch) is typically obtained from the strain holding test (SHT) or pressure holding test (PHT), which are a part of SBPT. The current predicted methods depend on a lot of parameters with simplified assumptions, thereby leading to an erroneous estimation of ch. This paper proposed a simplified method for estimating ch based on the observed excess pore water pressure (u) in the SHT. The proposed method is built based on the idea that the excess pore water pressure dissipates exponentially according to time. The key parameter “α” in the proposed method is verified using the field data of u. The α value can also be estimated from the slope of ui+1−ui line from early stage of dissipation process. Subsequently, the validation is performed to demonstrate the advantages of the proposed method by comparing it with other methods and the observation data.