Japanese Standard blowcount Nj
Japanese Standard blowcount Nj
(OP)
In the ASCE Technical Engineering and Design Guide SETTLEMENT ANALYSIS (US Army Corps of Engineers, No 9), Chapter 4, Table 4-1, there is a reference to Nj which is the blowcount by Japanese standards. How do this differ from the normal blowcount N from the Standard Penetration Test?





RE: Japanese Standard blowcount Nj
So: N(60) = N*(ER / 60)
Japanese systems are typ much more efficient than 60% (close to 80%). However, I'm unsure whether applying this energy correction will lead to the "blowcount by Japanese Standards."
RE: Japanese Standard blowcount Nj
RE: Japanese Standard blowcount Nj
Here it is.
Nj = 0.833(N1)60
The paper that mentions the Japanese hammer came from the following paper:
Ishihara, 1993. Liquefaction and Flow Failure During Earthquakes, Geotechnique, Vol. 43, No. 3, pp. 351-415.
RE: Japanese Standard blowcount Nj
RE: Japanese Standard blowcount Nj
RE: Japanese Standard blowcount Nj