Evaluation of soil profile and allowable Bearing capacity of soil using kunzelstab penetration test, kpt

Abstract

This study applied the kunzelstab penetration Test (KPT) or Light Penetrometer to examined penetration resistance values, geological profiles and estimate shear strength properties of soils. KPT tests were carried out on steep slopes that exhibit potential slope movement in Chiang Rai province. The principal uses of the KPT are examined; i.e. correction method for N’KPT’ soil profile and allowable bearing capacity of soil foundation. KPT tests were conducted at 13 boreholes, each measuring 4.00 m long along the crown of the slope. The results indicated the compacted layer and located the firm layer of soil foundation. The average allowable bearing capacities were 1.53 t/m2 at depth of 1.00-5.00 m and 17.06 t/m2 for 5.00-6.00 m depth respectively. Furthermore, this paper presents an analysis of the stability of a slope with the shear strength parameters of the soil and the geological profile were defined based on the results of KPT. The results of factor of safety were below the stable value for analysis cases with groundwater table. Test results demonstrate the usefulness of the KPT method in geotechnical investigations to estimate soil profile and bearing capacity efficiently and economically. This approach is also less time consuming compared to other geotechnical site investigation methods.