4.10 Uchiyama & Midorikawa (2004)

1) Reference

Yasuo Uchiyama and Saburoh Midorikawa, 2004, Practical Method to Evaluate Response Spectra of Bedrock Motions using amplification Factors for Site Classes, J. Struct. Constr. Eng., AIJ, No. 582, 39-46 (in Japanese).

2) Used strong motion data

- Area: Japan (K-NET, Hiroshima city earthquake information network, port area strong motion instrumentation)

- Type of earthquake:

- Period: 2000 Tottori-ken-seibu earthquake, 2001 Geiyo earthquake

- Number of events: 26

- Number of records:

- Magnitude:

3) Formula for estimation

Uchiyama and Midorikawa (2004) proposed a practical method to evaluate response spectra on bedrock using site amplification factor, Fa (site amplification factors for short periods) and Fv (site amplification factors for longer periods).

[Amplification factor within peak ground acceleration (ground condition B)]

Fa: amplification factor (0.1-0.5 period)

Fv: amplification factor (0.5-1.5 period)

Ss: acceleration response spectra (0.2 period)

Sl: acceleration response spectra (1.0 period)

Table 4.10-1 Site classification based on average shear-wave velocity

Table 4.10-2 Regression coefficients for formula for estimation

[Amplification factor with function of period]

a(T): amplification factor

a1(T): absolute value of amplification factor

a2(T): correction factor to astringe amplification factor to 1.0 at T6

Figure 4.10-1 Model of site amplification factor

Table 4.10-3 Set up break period T5

Table 4.10-4 List of the examination object station

Figure 4.10-2 Estimated bedrock motion spectrum and site amplification factor