Abstract: There are many factors affecting the results of laboratory compaction test, such as, sample preparation methods, compaction standard applied, compactive energy applied, soil moisture contents, height of residual soil in the container, particle size distribution, organic content in the sample, etc. The influence of soil types, moisture content, particle size distribution and organic matter on the test results is evaluated in this paper. The influence factors in the test procedures, such as sample preparation methods, compactive energy, residual soil height in the container and repetitive use of soil samples, are also analyzed in detail. The following conclusions could be drawn based on the evaluation results: Oven dried soils are recommended in the compaction tests. The height of residual soil should be strictly limited within 6 mm. The particle size distribution is an important factor. Through the analysis and discussion of these factors, the soil compaction results can be improved.

Key words: Compaction Standards, Compactive Energy, Particle size, Height of Residual Soil, Influence Factors