Some Methods on Mechanism to Decrease Seismic Force Applied to Building

The Shock and Vibration Digest. Volume 14, Number 5

“…Extensive research has been done on the validity of equation (8) and the reduced value of Se due to the notch [5,13,14,[17][18][19][20]. It represents the experimental data very well.…”

“…It has been observed in the literature on fatigue design of machine elements that (Cf Se ) is used in place of Se in equation (8). This approach assumes that Cf has no effect on the fatigue strength at N = 10 3 .…”

“…The equation makes use of the strain hardening exponent in the true stress-true strain equation for plastic behavior, fraction reduction in the area, strain offset, and true strain at fracture in static tensile test. Equation (8) is valid for N > 10 3 [17]. The proposed relationship for Sj [17] is difficult to use for fatigue design of machine elements due to the lack of required data; but the relationship illustrates that the S-N diagram [15,161 for N < 10 3 can be completed by connecting S u at N = 1 to 0.9 S u at N = 10 J by a straight line on the log-log scale for carbon steels, for 50% reliability.…”

“…The effect of the vertical load on yielded columns could render the system impractical. A more recent paper [8] resurrects the soft first story concept in a proposed structural design scheme involving a double basement and special construction over three lower floors.…”

“…Experiments have been carried out with notched fatigue specimens and specimens whose fatigue strength has been reduced under combined loading (bending and torsion). The data distribution follows somewhat the form defined by equation (1 that Se is replaced by the reduced fatigue strength Se defined [5][6][7][8][9][10][11][12][13] by S -C, S' e re (5) Cf is the overall fatigue strength reduction factor. At present, defining its components is a major research topic in the study of the fatigue of metals and machine elements.…”