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y the towers. Although it is difficult without video images of the traffic condition toidentify the vehicles that resulted in the deck vibration, three distinct events likelyoccurred as marked by numbered dashed lines in Figure 3.2. The north side of the bridgedeck carries the westbound traffic on the state highway 74 as directed by the dashed lines.If a car or truck was driven at 50–100 km/h, the time required to move the vehicle fromR6 to L2 is approximately 18–36 sec., which is consistent with the slope of the 3 dashedlines in Figure 3.2. It is speculated that, along the first path, a group of cars drove throughthe middle of the east side span at approximately 43 sec. and arrived at the middle of thewest side span at 65 sec. Along the third path, a heavy truck may have driven through thebridge at a slightly slower speed. Another group of cars may have driven through thebridge at a continuously reduced speed along the second path. The acceleration on thenorth side of the deck may also be somewhat affected by the eastbound traffic along thesouth side of the bridge deck.(a) North side of deck at middle of west side span (L2)1 2 3(b) North side of deck at Pier 2 (L4)(c) North side of deck at middle of main span (C2)(d) North side of deck at Pier 3 (R4)Figure 3.2(e) North side of deck at middle of east side span (R6)Vertical accelerations at deck under traffic loadingFor the May 1, 2005 earthquake, the time histories are shown in Figure 3.3. From the topto bottom, the acceleration responses shown in Figure 3.3 are for channels L3, L5, C1,R1, and R3, respectively. Since the L3 and R3 channels are at the deck near the supports,their responses are significantly smaller than those of L5, C1, and R1.20
(a) South side of deck at support of Pier 2 (L3)(b) South side of deck at ¼ west of main span (L5)(c) South side of deck at middle of main span (C1)(d) South side of deck at ¼ east of main span (R1)Figure 3.3(e) South side of deck at support of Pier 3 (R3)Vertical accelerations at deck under earthquake excitation3.3.2. Transverse vibrationTraffic-induced vibration is weak, particularly in the longitudinal and transversedirections, and also has a limited bandwidth. Therefore, some of the vibration modes maynot be triggered by traffic loading. To see the general variation of the lateral vibration,Figure 3.4 shows the lateral accelerations at the top and middle of the towers at Piers 2and 3. The vibration at the top is shown to be significantly stronger than that at themiddle of tower. Both are weaker than the vertical vibration at the bridge deck presentedin Figure 3.2.21
Page 1 and 2: Organizational Results Research Rep
Page 3 and 4: TECHNICAL REPORT DOCUMENTATION PAGE
Page 5 and 6: Executive SummaryOpen to traffic on
Page 7 and 8: 8. All cables behave elastically un
Page 9 and 10: Table of ContentsExecutive summary.
Page 11 and 12: List of Figure CaptionsFigure 1.1 A
Page 13 and 14: Figure 5.30 29 th mode shape (1.032
Page 15 and 16: 1. Introduction1.1. GeneralCable-st
Page 17 and 18: Figure 1.1Artist rendering of the B
Page 19 and 20: Expansionand lateralearthquakerestr
Page 21 and 22: 3. Evaluate the model by conducting
Page 23 and 24: 2. Automatic Retrieval of Peak Acce
Page 25 and 26: 2.2.3. Map/Find stationsClicking th
Page 27 and 28: 2.2.5. Displaying seismogramsTo dis
Page 29 and 30: Figure 2.8Directory chooser2.2.6. S
Page 31 and 32: 3.2. Seismic instrumentation networ
Page 33: The main bridge from Bent 1 to Pier
Page 37 and 38: (a) North side of deck at middle of
Page 39 and 40: The seismic responses at the top (T
Page 41 and 42: Polyreference Complex Exponential (
Page 43 and 44: are evaluated and presented in Figu
Page 45 and 46: 0.353.50.330.252.5Amplitude0.20.15A
Page 47 and 48: 1 x 10-4 Frequency(Hz)Amplitude0.90
Page 49 and 50: Amplitude0.20.180.160.140.120.10.08
Page 51 and 52: Amplitude0.20.180.160.140.120.10.08
Page 53 and 54: 1.20.80.400 100 200 300 400 500 600
Page 55 and 56: 4. Finite Element Modeling of Bill
Page 57 and 58: Since the cable stays are connected
Page 59 and 60: Table 4.3Initial property of cables
Page 61 and 62: Table 4.4Spring and damping coeffic
Page 63 and 64: (a) View of the entire bridge(b) Vi
Page 65 and 66: 4.6. RemarksA detailed 3-D FE model
Page 67 and 68: knω = (5.4)nm nSimilarly, when dam
Page 69 and 70: mainly corresponds to the vertical
Page 71 and 72: thFigure 5.10 9 mode shape (0.740Hz
Page 73 and 74: thFigure 5.19 18 mode shape (0.947H
Page 75 and 76: Figure 5.27 26 th mode shape (0.977
Page 77 and 78: When the bridge deck moves up and d
Page 79 and 80: 1.1Frequency (Hz)0.90.70.5BC Case 1
Page 81 and 82: 1.1Frequency(Hz)0.90.70.5Plus 0Plus
Page 83 and 84: no difference among the three cases
Page 85 and 86:
The FE model of the bridge was vali
Page 87 and 88:
10.6TestFE model0.2-0.20 100 200 30
Page 89 and 90:
1.20.80.40-0.4TestFE model0 100 200
Page 91 and 92:
differences is that the exact locat
Page 93 and 94:
(a) Vertical acceleration time hist
Page 95 and 96:
The FE model of the cable-stayed br
Page 97 and 98:
Displacement (m)0.30.20.10-0.1-0.2X
Page 99 and 100:
Station D1 (before amplification) a
Page 101 and 102:
ending of the tower as shown in Fig
Page 103 and 104:
symmetric about the centerline of t
Page 105 and 106:
Tensile stress (MPa)800750700650600
Page 107 and 108:
7. Conclusions and RecommendationsB
Page 109 and 110:
The vast arrays of acceleration dat
Page 111 and 112:
14. Cunha A, Caetano and Delgado T.
Page 113 and 114:
42. Song, W., Giraldo, D.F., Clayto
Page 115 and 116:
Figure A.2 Vertical stiffness and d
Page 117 and 118:
A.2 Group Interaction FactorThe cro
Page 119 and 120:
For a group of piles with identical
Page 121:
Missouri Department of Transportati
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