Page 156 - Dynamic Loading and Design of Structures
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Figure 4.10 Elastic design spectrum corresponding to a PGA of 0.5 g, 5% damping, and one sigma
cumulative probability (Newmark and Hall, 1982).
Table 4.1 Relative values of spectrum amplification factors (Newmark and Hall, 1 982).
Percent of critical damping Amplification factor for
Acceleration (A) Velocity (V) Displacement (D)
2 2.74 (3.66)* 2.03 (2.92) 1.63(2.42)
5 2.12(2.71) 1.65 (2.30) 1.39(2.01)
10 1.64(1.99) 1.37(1.84) 1.20(1.69)
20 1.17(1.26) 1.08(1.37) 1.01 (1.38)
* Median value (1σvalue).
(4.12)
where the constants c1 and c2 should be calculated on the basis of statistical analysis of
appropriately selected accelerograms. The calculated values of A, V, and D should be
multiplied by the corresponding amplification factors from Table 4.1.
