On the Possibility of Testing Miocene Clay from Cracow Area using Weight Sounding Test (WST)

Abstract

Polish standards concerning field investigation with the use of a Weight Sounding Test (WST) probe give interpretation of results for non-cohesive soils only. The lack of such interpretation for cohesive soils excludes this testing equipment from use. This paper presents the results of geotechnical site investigation and laboratory tests performed for Miocene clays in Carpathian Foredeep in the Cracow area. Based on the analysis of the results a correlation was determined between the characteristic values for the WST probe (number of half-turns N WST ) and the selected properties of Miocene clays. The article is an attempt to create a complete interpretation of test results obtained for cohesive soil with WST equipment.

Evaluation of Undrained Shear Strength of Miocene Clay from the Weight Sounding Test (WST)

“…Additionally, samples for subsequent laboratory testing (sample category B) were collected from the boreholes at every 1 m. In the next six boreholes (A-F), samples for laboratory strength testing were also taken at every 1 m throughout the depth (sample category A). Moreover, macroscopic description mostly aimed at the assessment of clay state was conducted during the field testing (Olesiak, 2010(Olesiak, , 2011(Olesiak, , 2013(Olesiak, , 2014a(Olesiak, , 2014b. Summary of the FVT field testing results and selected laboratory tests (Olesiak, 2010;2011;2013;2014a;2014b) In order to calculate the undrained shear strength during the WST testing, a measurement of the torque moment was taken.…”

“…Moreover, macroscopic description mostly aimed at the assessment of clay state was conducted during the field testing (Olesiak, 2010(Olesiak, , 2011(Olesiak, , 2013(Olesiak, , 2014a(Olesiak, , 2014b. Summary of the FVT field testing results and selected laboratory tests (Olesiak, 2010;2011;2013;2014a;2014b) In order to calculate the undrained shear strength during the WST testing, a measurement of the torque moment was taken. Subsequently, these results were compared with the results of the FVT testing, where the torque moment was tested indirectly too.…”

“…1). The WST tests were performed as deep as 6.5 m and the drilling reached the depth of 6 m. (Olesiak, 2010;2014b), b) rectangular (Olesiak, 2011;2013;2014a) FVT testing was conducted in six boreholes (I-VI) and included measurements of the undrained shear strength c fv and remoulded shear strength c rv , at every 1 m throughout the depth. The FVT testing results and the average strength values from the six boreholes are presented in Table 1.…”

“…-load W WST or number of half-turns N WST , for each 10 cm of penetration (Olesiak, 2010;2011;2013;2014a;2014b) In order to determine the torque moment values at a specific depth the following calculations were made. Firstly, the arithmetic mean of the measured torque moments within a single test for every 10 cm of penetration was established:…”

“…Geotechnical field testing was conducted in five test sites (Olesiak, 2010(Olesiak, , 2011(Olesiak, , 2013(Olesiak, , 2014a(Olesiak, , 2014b. On the chosen study area, a testing field was established in the shape of a square or rectangle and with the dimensions of 20×20 or 20×16 m and surface areas of 400 m 2 and 320 m 2 .…”