Abstract
M.Tech. (Civil Engineering)
Effective planning, design and construction of infrastructures such as roads, buildings, dams, bridges, airports and alike, which are either built in, on, or with soil, require that the types and properties of the soils involved are known as accurately as possible, before infrastructure design and construction. Therefore, it is crucial that soil testing laboratories produce test results that correctly represent the soil’s behavioural characteristics relating to its suitability for a given project or development.
Although there are well established and standardised testing methods for the determination of frequently required types of laboratory soil tests for design and construction of infrastructure, including the Atterberg limits, particle size distribution, compaction and consolidation tests in the civil engineering industry, there is limited knowledge of the extent and severity of disparities in the test results of these types of tests. This is more relevant concerning test results of Atterberg limits and particle size distribution test results which are used for soil classification and correlations to other soil properties. Furthermore, natural soils are formed under different environmental conditions, resulting in different soil types. The discrepancies due to the effects of soil types, miscellaneous (dispersing agents), and standardised testing procedures in Atterberg limits and particle size distribution tests are not well known.
The study was conducted: (i) to evaluate the effects of soil types, dispersing agents and recognised standard test methods on Atterberg limits and particle size distribution test results, following replicate testing, (ii) to investigate the extent, severity and the possible causes of discrepancies in the test results of Atterberg limits, particle size distribution, compaction and consolidation tests produced by various laboratories in the industry, following inter-laboratory testing and (iii) to determine the accuracy and repeatability of test results based on replicate tests, and (iv) to identify disparities and their possible causes in the inter-laboratory test results.