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Sylmar 90, (2) Newhall 90, and (3) El Centro. As evident from Table 4 the comparison is satisfactory
indicating'the accuracy of the analytical model. In addition it is worth noting in Table 4 that in the
experimental results of Sylmar 90, Newhall 90, and El Centro the base displacement is reduced further by
15 to 20 % in passive high damping case (4 volts) when compared to passive low damping (0 volts) case;
this occurs due to increase in peak total force at the isolation level in the high damping case by 15 to 45
% as compared to the low damping case. In the controlled case with smart damping the base displacement
is further reduced by 10 to 15% while the peak total force at the isolation level is less than that of the
high damping case. The controlled case reduces the base displacement, when compared to passive low and
high damping cases, with no further increase in force as compared to passive high damping (4 volt) case.
Also interstory drifts in the controlled case, presented in Table 4, are smaller than the passive high damping
case, while the accelerations remain bounded. From Table 4 it is clearly evident that the reductions in base
displacement and total isolation force in the experimental case are better than the analytical case.
Table 2 Interstory Drifts of the Two-story Smart Sliding Isolated Structure
Earthquake First Story Drift (cm) Second Story Drift (cm)
El Centro
Sylmar 90 (80%)
Sylmar 90
Sylmar 360
Newhall 90
Newhall 360
Kobe NS(80%)
Kobe NS
KobeEW
OVolt
0.111
0.109
0.121
0.149
0.129
0.137
0.134
0.14
0.12
4 Volt
0.136
0.144
0.157
0.165
0.155
0.179
0.158
0.18
0.153
Control
0.136
0.126
0.156
0.15
0.141
0.159
0.151
0.158
0.145
OVolt
0.15
0.143
0.148
0.181
0.162
0.153
0.162
0.169
0.137
4 Volt
0.166
0.181
0.201
0.215
0.222
0.227
0.205
0.222
0.191
Control
0.166
0.157
0.2
0.19
0.209
0.187
0.187
0.2
0.172
Table 3 Acceleration Response of the Two-story Smart Sliding Isolated Structure
Earthquake Base Ace. cm) First Fl. Ace. (g) Second Fl. Acc.(g)
El Centro
Sylmar 90 (80%)
Sylmar 90
Sylmar 360
Newhall 90
Newhall 360
Kobe NS(80%)
Kobe NS
KobeEW
0 V
0.45
0.48
0.51
0.55
0.56
0.47
0.56
0.633
0.474
4V
0.76
0.55
0.61
0.63
0.75
0.74
0.752
0.81
0.64
Cont.
0.75
0.51
0.61
0.6
0.73
0.66
0.7
0.736
0.611
0 V
0.352
0.333
0.41
0.55
0.359
0.46
0.372
0.47
0.42
4 V
0.66
0.435
0.49
0.564
0.60
0.49
0.486
0.524
0.54
Cont.
0.66
0.412
0.489
0.55
0.60
0.489
0.485
0.506
0.518
0 V
0.497
0.478
0.5
0.702
0.551
0.55
0.59
0.597
0.494
4V
0.541
0.576
0.65
0.679
0.785
0.79
0.806
0.789
0.66
Cont.
0.54
0.515
0.645
0.631
0.774
0.664
0.72
0.693
0.6
Earthquake
Sylmar90
Sylmar 90
Sylmar 90
Newk0190
Newhall 90
Newhall 90
El Centro
El Centro
El Centro
Table 4 Comparison of Analytical and Experimental Results
MRD Relative Base Total Force First Story Second Story
Disp. (cm.) Isol. Lvl./Wt. Drift (cm) Drift (cm)
Expt. Anal. Expt. Anal. Expt. Anal Expt. Anal.
0.0 V 2.179 2.293 0.212 0.224 0.113 0.109 0.127 0.143
40V 1.761 1.649 0.28 0.263 0.139 0.144 0.147 0.181
Control 1.409 1.484 0.26 0.26 0.128 0.126 0.141 0.157
0.0 V 1.914 1.815 0.214 0.21 0.123 0.129 0.122 0.162
4.0V 1.613 1.614 0.28 0.28 0.185 0.155 0.192 0.222
Control 1.411 1.276 0.241 0.261 0.163 0.141 0.159 0.209
0.0 V 0.969 0.938 0.166 0.16 0.098 0.111 0.142 0.15
4.0V 0.928 0.847 0.246 0.244 0.131 0.136 0.159 0.166
Control 0.743 0.775 0.24 0.24 0.119 0.136 0.142 0.166