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mitigate seismic failure of rectangular RC bridge columns due to a lack of lateral confinement, improper lap-splice or inadequate shear capacity. In addition, rectangular steel jacketing can effectively prevent a shear-deficient column from shear failure; however, it is not effective in improving the flexural ductility. 500 250 BMR-3 Vmax=290kN 500 250 SR-1 Vmax=456kN Force(kN) 0 -250 Force(kN) 0 -250 Force(kN) Force(kN) Force(kN) -500 500 250 0 -250 -500 800 400 0 -400 -800 800 400 0 -400 -800 -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) SR-2 Vmax=400kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) BMRL100 P=0.15f'cAg =1400kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) SRL2 P=0.15f'cAg =1400kN Vmax=- 368kN Vmax=602kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) Force(kN) Force(kN) Force(kN) -500 500 250 0 -250 -500 800 400 0 -400 -800 800 400 0 -400 -800 -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) SR-3 Vmax=418kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) SRL1 P=0.15f'cAg =1400kN Vmax= - 622kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) BMRL100 SRL1 SRL2 -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) Force(kN) Force(kN) Force(kN) 500 250 0 -250 SR-4 Vmax=423kN -500 -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) 1200 BMRS 600 P=0.15f'cAg =1400kN 0 -600 -1200 1200 600 0 -600 -1200 SRS2 P=0.15f'cAg =1400kN Vmax=- 722kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) Vmax= 982kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) Force(kN) Force(kN) Force(kN) 500 250 0 -250 -500 1200 600 0 -600 -1200 1200 600 0 -600 -1200 P=0.15f'cAg =1400kN BMR-3 SR-1 SR-2 SR-3 SR-4 -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(% radian) SRS1 P=0.15f'cAg =1400kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) BMRS SRS1 SRS2 FRS Figure 1 Hysteresis loop of the retrofitted Rectangular RC columns using steel Jacket Vmax= 1086kN -8 -6 -4 -2 0 2 4 6 8 Drift Ratio(%) 800 400 BMR2 400 BMR3 600 BMRS 400 BMRL100 400 200 200 200 200 0 0 0 0 -200 -200 -200 -200 -400 -400 -400 -600 -400 -800 -200 -100 0 100 200 Displacement(mm) -200 -100 0 100 200 Displacement(mm) 1000 -200 -100 0 100 200 Displacement(mm) -200 -100 0 100 200 Displacement(mm) 400 FR1 400 FR2 750 FRS 400 FRL100 200 200 500 200 250 0 0 0 0 -250 -200 -200 -200 -500 -400 -400 -750 -400 -1000 -200 -100 0 100 200 Displacement(mm) -200 -100 0 100 200 Displacement(mm) -200 -100 0 100 200 Displacement(mm) -200 -100 0 100 200 Displacement(mm) Figure 2 Hysteresis loop of the retrofitted Rectangular RC columns using FRP Jacket Test results for Fig. 2 show that failure of the flexural type specimen under larger axial load will result in speeding up the degradation of strength and energy dissipation capacity. In addition, standard hoop arrangements can gain better confinement than the double-U shaped alternation arrangement used in many existing bridges. For shear failure mode specimens, specimen retrofitted by wrapping FRP shows great performance in improving shear strength, and transfers the failure mode to flexural-shear type. For lap spliced -108-
failure mode specimens, applying CFRP directly can’t provide enough confinement stress to increase frictional force between the lap-spliced longitudinal reinforcements From the other test results for seismic retrofit of circular RC bridge column using steel jacketing and CFRP (Hwang and Hseih 1999; Hwang and Kuo 2000) concluded that the retrofit using steel jacketing is effective in enhancing the seismic resistance of existing circular RC bridge column. With steel jacketing and CFRP jacketing, the failure mode changes from flexural failure to the breaking of longitudinal bar in the bottom of the columns, and the ductility and maximum lateral force have increased. For lap splice failure mode specimens, using steel and CFRP jacketing can tremendously increase the confinement strength and ductility of bridges columns. Also, the more layers of CFRP can obtain higher ductility. On the other hand, for shear failure mode specimen, even though using steel and CFRP jacketing can also tremendously increase the confinement strength and ductility of bridge columns, more layers of CFRP may not have higher ductility. ROCKING EXPERIMENTS FOR BRIDGE PIERS WITH SPREAD FOOTINGS Background and Objectives After chi-chi earthquake, the design earthquake intensities of some area in Taiwan were shifted to a higher value; thus a great number of bridges need to be retrofitted. As the retrofitting work leads to a higher plastic moment capacity of the columns, the design force for the foundation needs to be increased based on capacity design. In order to satisfy the stability check of a spread footing under the application of this plastic moment transferred from the column base, some of the retrofitting works resulted in uneconomically large spread footings. Some newly designed engineering practices also met the similar situation. According to previous design code in Taiwan, the footing uplift involving separation of footing from subsoil is permitted only up to one-half of the foundation base area as the applied moment reaches the value of plastic moment capacity of the column. The reason for this provision is that rocking of spread footings is still not a favorable mechanism. However, recent researches have indicated that rocking itself may not be detrimental to seismic performance and in fact can act as a form of seismic isolation mechanism. In order to gain a better understanding of the problem of rocking and then to get more confidence to update the seismic design code and seismic evaluation guidelines, two series of rocking experiments were performed at NCREE. Experimental Program For the first series of experiments (Hung et al. 2008; 2010a), a total of three circular RC columns with spread footings were tested. Using pseudo-dynamic tests and a cyclic loading test, these columns were subjected to different levels of earthquake accelerations, including a near field ground motion. The focus of this experiment was to investigate the rocking behavior of both lightly transverse reinforced columns and retrofitted columns in order to clarify that if the widening and strengthening of the foundations to limit the rocking mechanism of spread footing is necessary for the retrofit work. These three columns were named specimens A, B and C, respectively. These columns measured 60 cm in diameter with a clear height of 3.4 m, were poorly confined and were lap-spliced above the top of the foundation. The columns were reinforced with 26-D19 longitudinal reinforcing bars, and were transversely reinforced with D10 perimeter hoops spaced 12.7 cm apart, corresponding to an insufficient volumetric confinement ratio of ρ s = 0.0039. Other material properties for these test columns were as follows: concrete compressive strength f c ’ = 278 kg/cm 2 ; yield strength of longitudinal reinforcements F y = 3840 kg/cm 2 . In order to investigate the rocking behavior of a retrofitted column with a ductility capacity that meets the requirement specified by the design code, one of the test columns, specimen C, was wrapped with 6 mm thick A36 steel plate jacketing with a length of 150 cm. During the tests, one as-built test column (specimen B) and the retrofitted column (specimen C) were rested on a neoprene pad to allow the rocking to take place. Another as-built column (specimen A) was constrained to the strong floor during testing to represent a benchmark test with fixed base condition. The summary of the test sequence is shown in Table 4. In this table, TH1 and TH2 represent a code compatible medium earthquake and a code compatible design earthquake, respectively. TH3 and TH4 are the near-field ground motions recorded during Chi-Chi earthquake, but were scaled to have the same PGA of the code compatible ones TH1 and TH2, respectively. Fig. 3 illustrates the test setup. In the case where the rocking mode of the foundation was restrained (Fig. 3a), four tie-down rods were placed through the foundation and anchored into the strong floor of the laboratory. In the case where the rocking mechanism was considered (Fig. 3b), and the square footings were rested on a neoprene pad, simulating a spread footing foundation in a stiff soil. By comparing the experimental response of the retrofitted column with that of the as-built one, the interaction effect of the rocking on the ductility demand and the strength demand of the columns was identified. A critical side effect of increasing the displacement response at the deck -109-
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Proceedings of the 5th Cross-strait
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SCIENTIFIC COMMITTEE Chairman Jan-M
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ORGANIZING COMMITTEE Co-chairmen Yi
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设计大师金问鲁教授
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TABLE OF CONTENTS Scientific Commit
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J.T. Shi & L. Su Impact of Spatial
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Temperature Effect on Variation of
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Trace Analysis of Mechanical Respon
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Keynote Lectures
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图 1 海峡大桥三个路
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非主通航孔的跨径应
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The 5th Cross-strait Conference on
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图 3 空间结构按单元
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图 7 多面体空间框架
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图 14 内蒙古响沙湾沙
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5.3. MRF3 索穹顶 — 网壳
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图 29 杭州黄龙体育中
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(a) 鸟瞰图 (b) 计算模型
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As it is conventional, the displace
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⎡ n n ⎤ ⎢q 1 0( z− Li) q0(
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frequencies of interest and the tra
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Another phenomenon observed from Fi
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刚塑性平面应变极限
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采用数值极限分析法
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为了推测浅埋隧洞破
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鹤梁岩壁面上至今已
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图 6 黄庭坚题铭 “ 元
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图 16 巫山神女图 17 长
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五、历年来研究过的
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在会议结束前给我半
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图 31 院士建议文件的
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科所、重庆交通学院
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图 37 白鹤梁题刻中段
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图 46 上下游水平交通
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图 59 参观廊道安装在
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9.6. 白鹤梁水下博物
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Page 88 and 89: The 5th Cross-strait Conference on
Page 90 and 91: (a) 模型 I (b) 模型 II (c)
Page 92 and 93: (a) 水平接缝处螺钉松
Page 94 and 95: 表 5 模型 I 在 9 度罕遇
Page 98 and 99: 1.2. 大型钢结构设计
Page 100 and 101: 5250 5000 i= 0.07 1 i= 0.07 5000 16
Page 102 and 103: A Pb Pa Pb A Pb Pa Pb Pa Pa ax Pb P
Page 104 and 105: (a) 预应力索布置 (b) 1/6
Page 106 and 107: 图 23 150m×150m 周边简支
Page 108 and 109: 图 27(a) 自重作用下结
Page 110: 四、结语 150m×150m 空间
Page 115 and 116: 通过上述技术创新平
Page 119 and 120: * θt r1cosθ r2cosθ2 = = (9) * 1
Page 121 and 122: 圖 10 水平軌枕方向之
Page 123 and 124: 圖 19 水平軌枕方向之
Page 125 and 126: 向量 r r &r r 的變化率
Page 127: Experimental Program More than 60 l
Page 131 and 132: columns were reinforced with three
Page 133 and 134: e formed at the column base and the
Page 135 and 136: Acceleration (g) 1 0.5 0 -0.5 Simul
Page 139 and 140: Table 2 Mix Proportion of the PDCC
Page 141 and 142: observed between the formwork and c
Page 143 and 144: In the above example, the GFRP with
Page 145 and 146: 构的加固修复 , 二是
Page 147 and 148: FRP 网格 FRP 筋和索 FRP 布
Page 149 and 150: (2) 钢筋 - 连续纤维复
Page 151 and 152: 生退化。拉伸强度相
Page 153 and 154: 图 16 两种纤维混杂增
Page 155 and 156: σ tf 混凝土构件粘结
Page 157 and 158: 新型抗震结构的荷载
Page 159 and 160: 的破坏过程也与柱 C-S
Page 161 and 162: 拉索频率阶数也低于
Page 163 and 164: A m plitude (m m ) 6000 5000 4000 3
Page 165 and 166: 产工艺进行探索性研
Page 167 and 168: Girders with Externally Prestressed
Page 169 and 170: concrete columns were documented by
Page 171 and 172: fatigue life of steel columns. Xiao
Page 173 and 174: Figure 11 Relationships between res
Page 175 and 176: 20. Xiao, Y. and Wu, H. (2000). “
Page 177 and 178: phenomenon, however, cannot be cons
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ase rock; H j ( iω) , H k ( iω) a
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For the coherency loss function bet
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Numerical Results The earthquake-in
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REFERENCES Bi, K., Hao, H. and Ren,
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Figure 3 Idealised bonded joint mod
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A = 0 1 (6a) B1 = −δ f (6b) f si
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Table 1 Test and predicted flexural
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COMPARISON OF FLEXURAL DEBONDING MO
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Figure 2 Location of smart aggregat
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Figure 5 Experimental setup Figure
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Figure 15 Impact location on FRP wr
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REFERENCES Bhalla, S. and Soh, C.K.
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The RVE, occupying a geometrical do
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[ ut ] is the tangential vector if
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extended to the resolution of the n
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469.1m,f m =55%,f I =45% -50 Σ 3 -
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頭混凝土護蓋敲除 ,
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發生夾片咬合失敗 ,
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會因設計長度不足 ,
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面之反推分析可知 ,
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因此連擋土牆本身之
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⎛τ ⎞ av ⎛amax ⎞⎛σ ⎞ v
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地液化与否初步判别
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等 (2000) [15] 在试验中都
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五、结论剪切波速法
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钢混凝土相当于将型
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A g — 混凝土毛截面面
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5.1. 大连市体育馆钢
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土梁中设立直线预应
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混凝土板外侧 , 受力
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试验采用跨中两点对
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为了深入了解槽型钢
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笔者针对已有结合部
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面 , 浇注的混凝土和
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(c) 波形钢腹板工字型
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manner for statistical analysis, (i
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3.3.1 Software System for Instrumen
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spectrum is obtained in an approxim
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e carried out once per maintenance
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The monitoring work is composed of
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displacement influence lines and st
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efers to data processing and storag
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Hong Kong Institution of Engineers.
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Monitoring Category Bridge Features
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9 Combination of Above Divided Sect
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Back to Routine Monitoring Not Exce
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Tsing Yi Stonecutters Figure 5 Layo
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Continuous Data Acquisition GPS Tim
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Y(+ve) Y T Temperature Distribution
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Type of Input Data Type of Data Pro
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Tsing Yi Stonecutters Stonecutters
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青衣 Tsing Yi 昂船洲 Stonec
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Accelerometer Fixing of Portable Ac
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Tsing Yi Stonecutters Bridge Stonec
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Structural Health Data Management S
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a mean recurrence interval with ext
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The present study is concerned with
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which all the variables have the sa
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450 35 400 30 350 300 25 ( 1.0E- 6)
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Structural Engineering and Mechanic
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provided in DBELA, a base rotation
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ξ ( μ − ) 3 eq −ξ0 = C + D 1
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equivalent displacements exceed the
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Displacement (cm) 70 60 50 40 30 20
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it give rather reasonable results,
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RANDOM FIELD AND SPATIAL AVERAGING
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satisfactorily when SOF is large bu
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those of the average shear strength
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then rinsed three times with deioni
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The Freundlich model can be express
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Ministry of Education for their fin
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United States.) The available site
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ACKNOWLEDGMENTS Financial support f
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the author has quoted the outdated
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Figure 5 The geological map of 2000
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Figure 11 Rock cores of vent brecci
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Due to the misidentification of roc
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ACKNOWLEDGEMENT The author would of
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Recently, as the development of fin
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( x ) ( x ) L m ( x ) ( x ) ( x ) L
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Step1: initializing the nonlinear o
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Table 1 The results of limit load m
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Khosravifard, A., Hematiyan, M.R. (
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阿坝州没有水库 , 凉
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汶川地震中属于溃坝
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缝宽约 2mm~5mm; 纵向断
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Problem with Seismic Hazard Analysi
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INADEQUACY OF TSUNAMI MITIGATION ST
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demonstrated that huge earthquake c
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三、粮库室内地面沉
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土层的物理力学参数
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笔者对 4# 粮库的沉降
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二国标中主动土压力
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表 3 c =0kPa 时不同的 δ
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的值比公式 (1) 的值小
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[1] 究等方面都有了新
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(3) 根据对隧道典型断
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水平收敛位移 (mm) 12.00
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THREE PROCEDURES FOR SCALING GROUND
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Peak displacement (m) 84, 50, 16 pe
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CONCLUSIONS Performance-based desig
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Figure 3 Physical diagrams of pile
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load-deflection curve at the pile h
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在此选取 Kondner [10] 及 Go
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及附加内力的简单方
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The dual is min * w, b, ξξ , s.t
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Table 1 The results of example 1 Re
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P P P P P P P P P P P P 4 5 4 A 2 4
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Figure 2 is a photograph of the int
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SHAKING TABLE TEST PROGRAM System i
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Force (N) 600 500 400 300 200 100 N
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Figure 9 Comparison of SAF-TMD and
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鋼線 , 近期更發展為
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三、吊橋基本資料表
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底端固定型式 □ 夾具
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4.2.3 吊橋扭轉行為之
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由式 (11)~(13) 可求得闭
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3.2 脉动风压时程结构
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4.2 主动控制力分析图
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egarded as a serviceability limit s
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observed that the measured values c
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_ Cumulative Frequency of Samples (
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三个项目基本概况对
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风作用下基底总 X 向 7
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主要技术指标对比表
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六、上部结构材料用
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m 2 , 三个项目采用混
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STADIUM ROOF BRIEF Jaber Al-Ahmad I
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a) 1st modal shape Figure.7 Modal s
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1) 所需的机具设备少
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6.1. 挠度选取典型加
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七、结论通过上述研
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where c = cope length,D = beam dept
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A post-ultimate stiffness of 200 MP
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Table 3 Summary of the variables of
Page 493 and 494:
Effects of Web Slenderness (d/t w )
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REFERENCES ABAQUS/Standard User’s
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规程 [7]。文献 [2]、[3]
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为探究球节点壁厚对
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[4] 王星 , 董石麟 , 完海
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一、前言鋼纜為斜張
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圖 1 愛蘭矮塔斜張橋
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態頻率後 , 由圖 6 可清
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素連接 , 假設兩構件
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图 3 半片梁的有限元
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加固前的钢筋混凝土
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and a corresponding shear strain of
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对温度变化效应进行
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典型节点 : 在钢结构
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钢结构第一阶振型为
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(a) 上支座节点 (b) 下支
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上部屋面钢结构下部
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验算 4、6 号线重力荷
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采用 SAP2000, 对各种截
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高屏溪引橋共包含五
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表 3 由高屏溪斜張橋
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圖 7 垂直撓曲第一振
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表 7 在 P2 橋墩不同沖
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