Statistical Analysis on Shear Strength Parameter from Index Properties of Fine-grained Soils

Emer Tucay Quezon,Mohammed Yasin,Tariku Tafari Bakala

doi:10.9734/jerr/2021/v20i417291

Abstract

Shear strength is the essential engineering property of soil required to analyze and design foundations, retaining walls, bridges, embankment, and related infrastructure. The laboratory equipment and field instruments are not sufficient in developing countries to obtain soil engineering properties, especially strength properties. Thus, Geotechnical engineers usually endeavor to develop statistical models that best fit a particular area and soil type, especially for analysis and design purposes. In this research, a Statistical Analysis on the Shear Strength parameter from the Index Properties of Fine-Grained Soils was studied. For predicting the undrained shear strength parameter, single linear regression (SLR) and multiple linear regressions (MLR) analyses were developed. To develop the intended statistical models for a study, SAS JMP Pro 13, SPSS v22, and Microsoft Excel-2013 software were introduced. The results of a study indicated that undrained shear strength(Cu) was significantly correlated with liquid limit(LL), plastic limit(PL), bulk density (ρbulk), dry density(ρdry), natural moisture content(NMC), and plasticity index(PI). While it was not significantly correlated with a specific gravity (Gs) and liquidity index (LI) of study area soil. Finally, a strong Model of Cu with a coefficient of determination (R2 = 0.806), good significance level, and less Std. error was obtained from multiple linear regression (MLR) analysis. The developed model can figure undrained shear strength parameter and wide application in the construction industry to minimize the cost, effort, and time for laboratory tests of shear strength parameter of a study area.

Highlights

One of the most significant engineering properties of soil is its capacity to respond sliding along internal surfaces within a mass
The undrained shear strength (Cu) was taken as the predicted variable while the predictors variables represented by the specific gravity, liquid limit, plastic limit, plasticity index, liquidity index, bulk density, dry density, and natural moisture content
The scatter plots' assessment indicated that a real indication of the points lie scattered arbitrarily as a straight or looks like a straight line, mainly for the liquid limit, plastic limit, natural moisture content, bulk density, dry density, and plasticity index

Summary

Introduction

One of the most significant engineering properties of soil is its capacity to respond sliding along internal surfaces within a mass. The stability of structures built on soil depends on the shearing resistance obtainable by the soil along probable surfaces of slippage [1]. It is quite essential that an engineer has to safeguard the structure is safe against shear catastrophe in the soil that supports it and does not undergo excessive settlement [2]. Undrained shear strength is one of the parameters to the bearing capacity of soil that could convey any structure rest on it. Some laboratory tests needed to obtain these parameters are costly and laborious, while other soil properties like index properties can be achieved quicker and cheaper. Index properties are the basis for distinguishing soils [3]

Methods

Results

Conclusion