Correlations between CPT, SPT and Soil Parameters for Khulna, Bangladesh

Abstract

Soil is naturally heterogeneous and non-uniform materials because it is made up of different types of matter. Understanding of soil parameters is one of the most complex tasks in geotechnical engineering. Several laboratory tests of soil have to carry out for engineering practices. Laboratory tests take too much time to accomplish and extravagant also. There is another alternative way to get soil parameters direct from soil field investigation report to save time and cost. The main objective of this study is to investigate the relationships of soil parameters with most commonly used soil investigating tools SPT and CPT. In this research, three pairs of CPT and SPT tests were performed at the riverbank of the Rupsha River, Khulna, Bangladesh. Different correlations have been developed in this paper among various field tests and laboratory tests. Analysis demonstrate that qtc/N1-60 ratio as a function of constant are better applicable to the local soils instead of D50 or fc based correlations. Finally, Internal angel of friction (ϕ) has been carried out using the correlation of SPT, CPT and compare with internal friction angle (ϕ) from Direct Shear (DS), and Multi-Stage Triaxial tests (MSTT) have been performed.