Evaluation of Silt Content in Natural Sand Used as Building Materials: A Statistical Analysis Approach

Abstract

AbstractThe excessive amount of silt within natural sand may reduce the bonding between sand and other constituent materials when used as building materials. The maximum amount allowed varies from 4 to 10%, and the allowable amount according to the Indonesian Standard (SNI S-04-1998-F) should be less than 5%. This study aims to evaluate the amount of silt in natural sand from several sand quarries in Lombok, Indonesia. The natural sand samples were collected from eight sand quarries in Lombok and the silt content was determined based on weight measurement. The study was designed to assess the silt content of each sand quarry against the SNI and also compared the silt content among the quarries. Two appropriate statistical analysis methods were applied; one-sample t-test and analysis of variance (ANOVA). The main conclusion drawn was that most of the natural sand in Lombok contains high silt content. The one-sample t-test results showed that the P-value of seven out of eight quarries was greater than the significance level (α), except for the sample taken from Sukadana. This value indicates that the silt content pretty close to the maximum value allowed by the SNI, which is already critical to be used as a building material. Meanwhile, the ANOVA result shows that the silt content from all sand quarries does not have a significant difference, which is indicated by the P-value greater than 0.05. Nevertheless, the result of a further analysis using Fisher’s test shows that the sand collected from Sukadana quarry has fairly low silt content and differs significantly from the others. It is strongly recommended to give a proper pre-treatment such cleaning process before using sand in this area as a building material.KeywordsSilt contentInferential statisticsMaterial assessment