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614 (1998). In this study, we also extended the 2D model from the bent in the intact stage to that hi the severe-damage stage by releasing boundary restriction at the ground end of pile 15 in Fig. 6. Table 1 shows the first ten undamped natural frequencies of the bent in its intact and severe-damage stages, in which the first to the third natural frequencies in vertical directions and their reduction percentage in its severe damage are also indicated. To simulate the damping effects, Rayleigh damping was used in modeling, i.e., [C] = a 0 [M] + a : [K] where M, C and K are the matrices of mass, damping and stiffness, 0 0 and a } are the constant coefficients. We used the same force in Fig. 2a to excite the 2D model hi Fig. 6 and obtained vibration response at nodes 53 and 37 in Fig. 6 that correspond to the same locations in sensors 15 and 13 in Fig. 1, respectively. Fig. 7a shows the Hilbert amplitude spectrum of the response at node 37 of the bent in intact stage with no damping, i.e., a 0 = a } = d = 0. The response energy focuses at frequency band with its center primarily around 12.0, 19.7, and 69.2 Hz that are respectively the fust three natural frequencies in vertical direction in Table 1. This can be further clarified in marginal amplitude spectrum in Fig. 7b. Without damping, the bent is fully excited at the natural frequencies. Therefore, the vibration energy at natural frequencies is typically higher than the excitation-inherited energy at chirp frequency. Consequently, the energy inherited from the excitation at chirp frequency is not clearly shown in Fig. 7a, except the strong portion with frequency band from 40-70 Hz at 3.5-5 s. With the damping, the relath e intensity of the energy from the structure and excitation should be changed, which can be seen from the Hilbert amplitude spectra in Figs. 7c,d with a Q = a : = d =0.00198 and 0.05305, respectively. Comparing Fig. 7c with Figs. 3a and noticing the fundamental natural frequency of the bent being 11.98 Hz, we can conclude that the excitation-inherited energy in Fig. 7c is associated with chirp frequency and other frequencies such as high-frequency band in 10-30 Hz during 0.3-0.8 s, and that the vibration energy is associated with frequency band around 10-13 Hz during 1-1.6 s. The damped fundamental natural frequency in vertical direction is identified in Fig. 7c around 11.5 Hz, smaller than the undamped one with 11.98 Hz in Table 1 which is consistent with the vibration theories. Due to the large damping used and strong excitation at chirp frequency, the vibration energy at natural frequencies are greatly suppressed and the excitation energy is inherited, in comparison with the undamping case (see Figs. 7a,c). This phenomenon can be further clarified by Fig. 7d with a large damping. Fig. 7d shows that the vibration energy at 10 Hz primarily at 1.4 s. Since the damping here is extremely high, the damped fundamental natural frequency is greatly downshifted from undamped one at 11.98 Hz to the current one at 10 Hz. It should be noted here that it is with the damping d=0,05305 that the ANSYS model in Fig. 6 generated time history responses that are similar to those in recordings such as Fig. 2b. This implies that real damping of bent 12 in the vertical direction is very high. Depicted in Figs. 8a,b are respectively the Hilbert amplitude spectra of the response at nodes 37 and 53 of the bent in severe-damage stage with a Q =a l =d =003979. Fig. 8b shows the vibration energy concentrates at 7 Hz from 0.5 to 1.2 s, i.e., the fundamental natural frequency of severe-damage bent in Table 1. In contrast, the dominant vibration energy in Fig. 8a is at around 12 Hz between 0.6-1 Hz and minor at 7 Hz at 1+ s. The difference of dominant response energy at frequency 7 Hz in Figs. 8a,b, i.e., damage-signature from recordings, helps identify qualitatively the damage column and severity.
615 Table 1: Fundamental natural frequencies of Bent 12 in intact and severe-damage stages, modeled by ANSYS software in terms of design specifications Natural frequencies in Hz (comments) 1st 2nd (1st vertical natural frequency) 3rd 4th (2nd vertical natural frequency) 5th 6th (3rd vertical natural frequency) 7th 8th 9th 10th Intact 3 99 11 98 14 84 19 68 44 01 69 22 93 88 104 45 106 37 108 49 Severe damage (decrease w r t intact) 3 29 6 95 (41 98%) 12 47 18 08 (8 13%) 39 19 52 50 (24 15%) 72 50 L_ 95 00 105 82 108 17 Figure 1 (left): Vibration tests of Bent 12 in the Trinity Relief River Bridge under excitations at the middle of the deck. Figure 2 (right): Bent 12 in intact stage, (a, top) Forcing function and (b, bottom) Recorded vibration at sensor 15. Figure 3a (left): Hilbert amplitude spectra of forcing function for vibration at sensor 15 of Bent 12 in intact stage. Figure 3b (right): Hilbert amplitude spectra of vibration at sensor 15 of Bent 12 in intact stage.
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Proceedings of the International Co
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vw:. PREFACE Dunng a time when eart
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OPENING ADDRESS By Prof. Yuchen Liu
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Vll scientific support in our call
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IX INTERNATIONAL ADVISORY COMMITTEE
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XI Engineering Seismology and Geote
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Xlll Progress in the Seismic Design
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XV Crustal Deformation Measurement
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Legal Impediments There are many im
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expectation of (i) expanding the fr
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10 Some applications of wireless te
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12 Smart Materials Smart materials,
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14 research and education in a mult
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19 On September 16, 1994, buildings
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21 Some people were injured while t
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23 tallest buildings in Hong Kong w
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25 Figure 12. Tsim Sha Tsui East an
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27 OTHER ONGOING WORKS Soil-pile-st
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29 Figure 18. The pounding experime
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31 ACKNOWLEDGMENTS The writers are
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35 Table 1. Records Used in the Dev
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37 Date 8/19/1976 10/5/1977 12/16/1
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39 (2) Here Y is the ground motion
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41 1 2 3 4567810 20 3040 SO 100 200
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43 of the resultant horizontal comp
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45 200 006 005 004 003 002 Rock, Mw
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47 en o_ KOCAELI DATA (Random Hor C
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Atkinson G.M., Boore D.M., Some Com
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52 BACKGROUND AND SCOPES In order t
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configurations of cylinder, and it
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l 56 X xT / ^ V^—Ê-^/i / X\ - yX
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58 59-74 (in Japanese) [7] ISHIKAWA
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60 accuracy and efficiency, have no
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62 f •c J — c. p «3 no Fig. 2
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64 VARIOUS TESTS AND DISSEMINATION
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66 response.. The post-earthquake i
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71 with the potential for self-diag
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73 Semi-active Hydraulic (SHD) Cont
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75 Table 1 Buildings currently unde
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77 and the inside of the damper cyl
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79 Figure 16. MR damper installatio
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81 sensors. New algorithms must be
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83 Kobon T. (1998). Mission and per
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87 for a period range less than 3.0
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89 tens or more than a hundred acce
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91 In order to validate the conclus
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93 Distance (km) """"--Âcc. (g) Ma
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95 CONCLUSION In this paper the imp
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ENGINEERING SEISMOLOGY AND GEOTECHN
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100 analyses. This paper reviews th
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102 A comparison of spectral amplit
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104 the high speed with which FFT c
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106 8. Gold, B. and C.M. Rader (197
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108 Displacement Curves", Dept. of
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I 000,000 100,000 Number of uniform
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Response and Fourier Spectra of Dig
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114 10 3 10 2 r | I lll| I | I | I
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116 analysis. Other techniques incl
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It has been found that G max applie
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120 PALEOLIQUEFACTION STUDIES IN ME
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Jardine, R.J., Potts, D.M., StJohn,
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124 has received more attention. In
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126 and log A tQ (/) is the mean so
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128 O 10 s Frequency (Hz) Frequency
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130 geometrical coefficient is near
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132 optimizing method in many engin
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134 Type-2 Fig.5 Three dimensional
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136 plane plane sliding x-z section
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141 1. System Definition define sys
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143 f«l-.J WJjfc >. « Relations -
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145 DS-5 Response Simulation across
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147 CM 1 CM 2 CM 3 CM-4 CM-5 CM-6 H
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151 Number of Pixels (Frequency) Th
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153 Red: possible impacted areas Gr
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155 Low reliability -(water-reflect
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Modem or Router Dial-up ISP The Int
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from observed images Fig 5 shows th
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163 Picked up building from image p
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167 evaluated by Seed's approximate
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169 R(z,N)is reached to 1 or more,
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171 subsoil and combined with the n
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174 defined target. Performance-bas
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176 (probability of being in or exc
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178 start to dominate the hazard at
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180 MAX STORY DUCTILITY vs NORM. ST
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185 Decision Making Support Tool' U
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189 31 Array Liujiaxia Reservoir Ar
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191 IV STATION YM kCED INTERVALS OF
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193 at different stations, the diff
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197 PROBLEMS AND CHALLENGES Earthqu
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199 Database s*n/ar_- ^ " Applicati
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201 o Fig. 7 VRML authoring - model
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SMART MATERIALS AND SMART STRUCTURE
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209 vector of measured control forc
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211 To examine the effect of the co
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213 from Fig. 2, we can get the res
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Proceedings of the Intel-national C
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217 where gjî = g(X fcTl , F^+ît
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219 3 360 Deg. Fault Normal (Jan. 1
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221 Earthquake Sylmar 90 Sylinar 90
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225 0.6965, and 0.7094 Hz, which ar
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227 Two displacement sensors are po
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229 14% to 45% (under El Centre ear
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233 g ^ w (4) Notice that the stabi
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235 modes. An energy drop will be o
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237 PPF controller. The second mode
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241 In order to determine the appar
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243 RESULTS AND DISCUSSIONS Figure
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245 100 150 200 250 300 Magnetic Fl
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249 WOLFE, MASRI, CAFFREY Synthetic
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251 WOLFE, MASRI, CAFFREY Transform
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253 WOLFE MASRI,CAFFREY in parallel
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STRUCTURAL ANALYSIS AND DESIGN
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258 separating the above three effe
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260 200 300 400 SHAKE Computed RSD^
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262 where H b is the building heigh
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264 6. ACKNOWLEDGEMENTS The work de
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266 The objectives of this paper pr
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268 The comparison between abovemen
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270 determine the span of the state
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the assumption of the bi-linear for
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274 There are several outstanding e
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276 buildings with different concre
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278 160,000 - 140,000 _^ d Concrete
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280 responded in a fairly similar m
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282 CONCLUSIONS In this paper, the
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284 Li B, Park, R. and Tanaka, H. (
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For simplicity, a linear distributi
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equation can be re- written as: 288
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290 DESIGN BASE SHEAR Equating the
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292 by using the computer program S
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294 mutation. Elitist strategy mean
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296 2.3 Premature Judgment and Comb
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298 (3) F 3 : De Jone's F 5 3 (Shek
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300 3.3 Test Conclusions From the t
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30; excitation. Also, the software
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304 concrete frames as documented i
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30€ NEURAL NETWORKS Development I
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308 ACKNOWLEDGEMENTS The research r
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310 In order to ensure the entire s
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312 Examples of Seismic Design In K
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314 earthquake load can be reduced
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Proceedings of the Intel national C
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319 broken. Therefore, joint elemen
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321 the highest probability to get
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325 DESIGN SPECIFICATIONS Overview
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327 Strength Degradation The streng
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I 329 file £dit Vww Select Constru
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333 (1) (2) Where f t and _/£ are
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335 JL dalt (10) Where Solution of
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337 Fig.9 Distribution of first pri
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341 DISPLACMENT-BASED NSF In this p
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343 Define the displacement of the
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345 EXAMPLE The nonlinear static an
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347 REFERENCE Code for seismic desi
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350 including Hong Kong are conside
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352 structural engineers. Although
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354 4) Structural characteristics R
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356 maintain economy of design but
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358 R C3&OC11 L8C34 USC3 •••
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363 DISPLACEMENT CALCULATION FOR GR
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365 As shown in the figure, a model
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367 history of a design earthquake
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371 reflects the structure's useful
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373 have a membership degree betwee
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375 of initialization of structure,
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377 REFERENCE Zadeh, L A (1965), "F
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.0,(r+l,,)] (0 + A (3) 383 -l.y)] (
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385 The first example is come from
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387 REFERENCES Leroueil, S. (2001).
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391 maximum friction force and ther
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393 the stiffness of the bracing an
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395 splacemen (m) Bared —Braced/D
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399 Figure 1: Two-surface Model Def
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401 time, one must integrate over t
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403 CONCLUSIONS In the previous sec
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407 Response Control by Magneto-Rhe
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409 s e a ooo j| soo y 0 c l83Hz ,5
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411 *fU O A 20 7 HA I , 2 4A .'.-%-
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415 Wind Velocity (t J Relative Dis
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417 Fig. 5 4ttractor (time lag=l) F
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419 concluded that the real time re
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422 (LQR/LQG), H M and the instanta
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424 damping ratio provided by the c
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426 by Eqn. 2.9 and Eqn. 2.12, resp
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428 Fig.5.4 shows the comparison of
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Innovation is driving control devic
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432 STRUCTURAL ENERGY DURING VIBRAT
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434 Equilibrium Price of Power With
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436 CONCLUSION The scope of this re
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438 The effectiveness of the seismi
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440 anti-symmetnc mode excited by t
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442 Base Isolation System The base
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444 each member along or adjacent t
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446 2 PROJECT PARTICIPANTS Concerni
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448 3.1.2 Investigations at Seyhan
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450 Fig. 4.2: principle drawing of
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452 no TMD — TMD with optimal tun
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454 In this paper, a stochastic opt
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456 The dynamical programming equat
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458 control strategy. Model reducti
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460 (AMDs) and the proposed control
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465 Specimen 1 Specimen 1 represent
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467 increased the beam moment stren
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469 3 4@8 ~T / C 4 #5 #3 stirrups 8
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473 Phase 2: The sliding of the bot
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475 4.2 Effect of Coefficient of Fr
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477 -ZETA=Q 05 -ZETA=010 -ZETA=015
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479 031 en 03 0029 P |Q 28 ~*—MR=
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482 stiffness or coefficient of vis
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484 solved for the Hamilton Jacobi-
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486 posed to be the accelerations o
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488 vlaxacccleiation [my O O O O
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490 INTRODUCTION In recent years, t
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492 Since earthquake motion has bee
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494 confirmed in the X direction. B
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496 yielding metallic dampers, and
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498 where the coefficients a m and
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500 modal damping ratio of 2% in ea
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502 CONCLUDING REMARKS The paper re
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504 semi-active and hybrid control
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506 Iiz2i(t)l
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508 defined as 114 - [ J* [•] 2 d
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Spencer, B.F., Jr. and Sain, M.K. (
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512 with the rapid success of seism
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Figure 3 summarizes the static push
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CONCLUSIONS 516 This paper presents
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518 1 OS h : 0 6 5 5 04 Transverse
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520 TABLE 1 REPRESENTATIVE MULTISTO
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522 obtained by simply averaging a
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524 levels of peak ground accelerat
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526 8 CONCLUSIONS This paper gives
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531 350.6m 142.7m .0130') i (468')
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533 cation corresponds to a node of
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535 listed separately. Vertical mod
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539 in which H = [H(t l ), H(t 2 ),
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541 identification results of struc
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543 history to be polluted. In the
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548 environment constraints and the
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550 where F is the fundamental matr
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552 drift ratio was determined as Y
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554 were observed in the vision-sys
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556 The most well-known Bayesian so
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558 achieved by the EKF estimates I
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560 0 2 4 5 3 10 12 14 16 18 20 0 2
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562 CONCLUSION In this study, the r
Page 580 and 581: 564 Figure 1 - Prototype wireless s
Page 582 and 583: 566 will vary from that of the ARX
Page 584 and 585: 568 A 11 25" 11 25" 1 T 1 11 25* !
Page 586 and 587: 570 CONCLUSION The realization of a
Page 588 and 589: 572 the structural response and ret
Page 590 and 591: 574 The ratios of base shear at dif
Page 592 and 593: 576 SECTION A-A COLUMN DETAIL AT TO
Page 594 and 595: 578 Stress Strain Fig. 6 Superelast
Page 596 and 597: 580 Genetic Algorithm(GA) and the M
Page 598 and 599: 582 IDENTIFICATION ALGORITHM State
Page 600 and 601: 584 the simulated structural respon
Page 602 and 603: 586 GA-MCF, the number of particles
Page 604 and 605: 588 instrumentation to monitor and
Page 606 and 607: 590 If we compare this peak value w
Page 608 and 609: 592 2.3 Sampling rate Structural mo
Page 610 and 611: 594 Any remote station that has the
Page 612 and 613: 596 or receives environmental infor
Page 614 and 615: 598 Comparisons of Proposed E-Monit
Page 616 and 617: 600 LCD display Earthquake Warning
Page 619 and 620: Proceedings of the International Co
Page 621 and 622: 605 Kishwaukee River Bridge consist
Page 623 and 624: 607 the table, the monthly maximum
Page 625 and 626: 609 3.2 L VDTData Analysis LVDT sen
Page 627 and 628: Proceedings of the International Co
Page 629: structural response energy with fre
Page 633 and 634: 617 JUSTS rs s." WUUR. 4 20O2 IS 44
Page 635 and 636: 1-1 INDEX OF CONTRIBUTORS Volumes I
Page 637: Ths OOO F X ^s dje foe return 01 ê
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