Abstract
Some decrease of N value in the dam foundation was caused during excavation of an earth fill dam. Substratum of the dam consists of Quarternary sandy soil, which was verified through standard penetration test and some soil tests to qualify actual condition of its decreases. Because the relative density and internal friction angle did not show any change before and after excavation, therefore the decrease of N value did not imply the decrease of original strength (rebound, loosening). Based on these examinations, the authors have carried out boring tests to identify improving condition of N value, and verified reasoning on the relation between N value and overburden load after embankment construction.
