Biplot analysis for mapping the soil sample characteristics of Rawa Jitu, Marga Tiga, and Teluk Ratai, Lampung Province

Abstract

The purpose of biplot analysis is to demonstrate a matrix by overlapping the vectors representing the row vectors with the vectors representing the column vectors of the matrix. Biplot is performed by outlining singular value decomposition (SVD). SVD aims to describe the singular value of the Y matrix which is an X matrix of size n x p which has been corrected with the mean and followed by the generation of the G and H matrices. Biplot results. The results of the biplot analysis on 3 groups of soil samples based on the similarity of soil characteristics for the Rawa Jitu and Marga Tiga areas are as follows: group 1 consists of soil samples that have the same maximum dry density, California bearing ratio, and specific weight of solids; group 2 consists of soil samples that have the similar Atterberg Plastic Limit, Atterberg Liquid Limit, and Atterberg Plasticity Index; while group 3 consisted of soil samples which had similar moisture content and optimum moisture content, and % Lose No. 200. It is different with the Teluk Ratai area where there are 2 groups of soil samples including group 1 consisting of soil samples that have the same maximum dry density, and % passing filter No. 200; group 2 consists of soil samples that have similarities from test results using the CBR or California Bearing Ratio, Atterberg Plastic Limit, Atterberg Liquid Limit, moisture content, and optimum moisture content. The highest diversity so that it can be said as a relatively high soil characteristic in Margatiga and Rawa Jitu is % Lose No. 200, while in the Teluk Ratai area, the highest diversity is at the Atterberg Liquid Limit. If there is an increase in the water content in the soil sample, then the Atterberg Liquid Limit and Atterberg Liquid Limit values will also increase and vice versa if the % passes filter No. 200 is smaller, there will be an increase in the CBR value.