Abstract
This paper deals with the uncertainty evaluation of different results of laboratory soil tests. The main objective of this study is to find out the cause of uncertainty in the result and its degree of effect, reliability of the results with specific uncertainty evaluations. In order to measure the uncertainty factor, seven types of physical properties tests and an unconfined compression test were carried out. It was measured that the range of test results of natural soil sample were large. Considering large differences in the range of test results, relatively expanded uncertainty method was applied. According to the test results, the unconfined compression strength showed the highest uncertainty of 37.2% whereas silt content of particle size distribution of physical property test showed 33.3%. The uncertainty of the remaining tests was ranged from 2.2 to 6.3%. It is understood that the prime factor to take place large difference in the uncertainty ratio of physical properties tests was due to lack of consistency of inconsistency of experimenter and types of soil. In case of unconfined compression strength, the large difference in the uncertainty ratio was comprehended due to lack of inconsistency of experimenter and apparatus.
