Journal of Jilin University(Engineering and Technology Edition) ›› 2023, Vol. 53 ›› Issue (6): 1621-1637.doi: 10.13229/j.cnki.jdxbgxb.20221428

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Finite element analysis method for mechanical properties of steel⁃concrete composite beam bridges with multiple damages

Jian-qing BU1(),Zhi-bo GUO2,Ji-ren ZHANG3,Jing-chuan XUN4,Xiao-ming HUANG5   

  1. 1.School of Traffic and Transportation,Shijiazhuang Tiedao University,Shijiazhuang 050043,China
    2.School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China
    3.School of Civil Engineering,Hunan University,Changsha 410082,China
    4.CSCEC Road and Bridge Group Co. ,Ltd. ,Shijiazhuang 050043,China
    5.School of Traffic and Transportation,Southeast University,Nanjing 210096,China
  • Received:2022-11-11 Online:2023-06-01 Published:2023-07-23

Abstract:

In order to propose the finite element analysis method of steel-concrete composite beam bridges with multiple damages, and find out the influence law of different damage types and degrees on the mechanical properties of steel-concrete composite beam bridge, firstly, the finite element simulation method of multi-damage combination of steel-concrete composite beam bridge and the quantitative assessment method of damage grade were studied. Then, based on the vehicle-bridge coupling vibration, the dynamic response of the steel-concrete composite beam bridge midspan and the acceleration response of the vehicle body under different vehicle speeds and different damage grades were analyzed; At last, the key section deflection, relative slip between slabs and beams and stress variation of steel-concrete composite beam bridge under different damage grades were studied. The results show that the multi-damage combination simulation method can effectively characterize the multi-component damage intertwined state of steel-concrete composite beam bridges and achieve the quantitative description of the multi-damage state of steel-concrete composite beam bridges. With the increase of the damage grade, the mid-span vertical vibration displacement and acceleration response peaks increased, and the vertical, lateral and pitch vibration acceleration of the vehicle body also showed the same change pattern, compared with the undamaged state, the maximum increase of its peak value is 2.16 times, 92.5 times, 205 times, 565 times and 235 times respectively. The deflection and slip of the key section also increased, and the stress at the lower edge of the steel beam did not change significantly, while the stress at the upper edge of the concrete slab increased significantly.

Key words: bridge and tunnel engineering, steel-concrete composite beam bridges, multi-damage characterization, damage grade assessment, vehicle-bridge coupling

CLC Number: 

  • U447

Fig.1

Concrete crack model"

Fig.2

Element geometry"

Table 1

Damage grade of bridge deck"

桥面等级桥面平度系数
下限几何平均上限
A81632
B3264128
C128256512
D51210242048
E204840968192

Table 2

Damage assessment criteria for steel- concrete composite beam bridges"

BCI≥9081~9071~8061~70<60
损伤等级

Table 3

Weight value of bridge structure damage index"

一级指标

一级

权重

二级指标模拟方法二级权重
桥面系0.2桥面破损修改桥面平整度1
上部结构0.4混凝土板裂缝刚度折减0.2
横隔板损伤刚度折减0.2
剪力钉断裂删除单元0.2
钢板梁微裂缝刚度折减0.2
支座损伤删除单元0.2
下部结构0.4下部结构混凝土剥落删除单元1

Table 4

Deduction value of bridge structure damage index"

损伤指标扣分值
1011~2021~3434~50>50
桥面破损等级ABCDE
混凝土板刚度退化/%<1010~2021~3031~40>40
横隔板刚度退化/%<1010~2021~3031~40>40
剪力钉断裂比例/%<1010~2021~3031~40>40
钢板梁刚度退化/%<1010~2021~3031~40>40
支座损伤比例/%<2021~4041~6061~80>80
下部结构混凝土剥落/m3<0.030.03~0.060.061~0.090.091~0.12>0.12

Fig.3

Finite element model"

Table 5

Multi-damage conditions of steel-concrete composite beam bridge"

参数工况1工况2工况3工况4工况5工况6
BCI1009084756454
损伤等级无损伤
桥面破损等级-ABCDE
混凝土刚度退化/%-1015202530
横隔板刚度退化/%-1015202530
剪力钉断裂数/个-120180240300360
钢板梁刚度退化/%-510152025
支座脱空-AA、BA、B、CA、B、C、DA、B、C、D
1号桥台破损体积/m3-0.030.050.070.090.11

Table 6

Space two axle vehicle model parameters"

参 数数值
总质量/t27.71
车体质量M1/t24.81
俯仰转动惯量Izx1/(kg·m2172 160
侧翻转动惯量Izy1/(kg·m231 496
1轴悬挂质量m1/t0.73
上(下)部弹簧刚度Ku1(Kl1)/(kN·m-1727.81(1 972.90)
上(下)部阻尼系数Cu1(Cl1)/(kN·s·m-12.19(0)
几何间距L1L2)/m4.56(1.69)
几何间距b/m1.10

Fig.4

Two axle vehicle model"

Fig.5

Vehicle bridge coupling program verification"

Fig.6

Vertical vibration displacement response at midspan of each damage grade under different vehicle speeds"

Fig.7

Vertical vibration displacement peak at midspan of each damage grade under different vehicle speeds"

Table 7

Maximum amplitude of vertical vibration displacement peak in midspan"

损伤等级车速/(km·h-1Amax/%
20406080
Amax/%185196201216
无损伤2.832.882.922.954.2
I4.924.965.045.052.6
II5.345.525.475.584.5
III6.076.256.506.639.2
IV7.177.237.648.0312
V8.218.528.789.3113.4

Fig.8

Vertical vibration acceleration response at midspan of each damage grade under different vehicle speeds"

Fig.9

Vertical vibration acceleration peak at midspan of each damage grade under different vehicle speeds"

Table 8

Maximum amplitude of vertical vibration acceleration peak in midspan"

损伤等级车速/(km·h-1Amax/%
20406080
Amax/%9250682942794060
无损伤0.020.070.140.167
I0.140.691.201.711121
II0.171.032.412.781535
III0.361.462.823.85969
IV0.873.685.996.90693
V1.874.856.137.52302

Fig.10

Vibration acceleration of vehicle body with different damage levels at different speeds"

Fig.11

Vehicle body vibration acceleration peak"

Table 9

Maximum amplitude of vertical vibration acceleration peak in midspan"

损伤等级车速/(km·h-1Amax/%
20406080
无损伤Ya0.020.060.100.15650
Xa0.0060.0130.0180.024300
Za0.0080.020.0460.076850
Ya0.300.380.420.5273
Xa0.121.652.433.272 625
Za0.120.140.320.37208
Ya0.500.750.840.9182
Xa0.781.522.642.99283
Za0.230.310.580.84265
Ya1.021.471.801.8379
Xa1.643.554.735.19216
Za0.600.611.061.36127
Ya1.182.803.004.00121
Xa3.045.936.148.81190
Za1.051.192.742.94180
Ya4.124.856.256.8157
Xa3.187.368.3511.22278
Za1.892.354.616.67253
Amax/%Ya20 5007 9836 4504 200
Xa49 40056 51546 28946 650
Za23 52511 6509 9228 676

Fig.12

Deflection change curve of bridges with different damage grades"

Table 10

Absolute slip value of steel-concrete composite interface"

桥梁位置无损伤
0C1.001.701.902.903.504.10
S0.911.001.101.231.301.49
L/8C0.961.001.102.102.803.50
S0.900.920.980.991.101.30
L/4C0.710.740.790.850.981.08
S0.680.700.720.770.880.95
L/2C0.430.570.590.610.690.70
S0.420.540.560.580.640.65

Fig.13

Relative slip value of steel-concrete composite interface"

Fig.14

Bending strength of midspan section"

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