双柱墩实桥爆炸试验与动力响应分析  

Field Test and Dynamic Response Analysis of Double- column Bridge Piers Under Blast Loading

作　　者：胡志坚[1] 耿浩[1] 刘辉[1,2] 陈昌萍 游勇利 方建桥 HU Zhi-jian;GENG Hao;LIU Hui;CHEN Chang-ping;YOU Yong-li;FANG Jian-qiao(School of Transportation and Logistics Engineering,Wuhan University of Technology,Wuhan 430063,Hubei,China;Jiangxi Traffic Engineering Group Co.Ltd.,Nanchang 330038,Jiangxi,China;School of Civil Engineering&Architecture,Xiamen University of Technology,Xiamen 361024,Fujian,China;Jiangxi Highway Research and Design Institute Co.Ltd.,Nanchang 330002,Jiangxi,China)

机构地区：[1]武汉理工大学交通与物流工程学院,湖北武汉430063 [2]江西省交通工程集团有限公司,江西南昌330038 [3]厦门理工学院土木工程与建筑学院,福建厦门361024 [4]江西省公路科研设计院有限公司,江西南昌330002

出　　处：《中国公路学报》2024年第11期102-112,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(52178510);江西省交通运输厅科技项目(2021Z0001)。

摘　　要：为了研究爆炸荷载作用下钢筋混凝土(RC)桥墩的抗爆性能,对一座三跨简支梁桥的圆形截面双柱墩开展了实桥爆炸试验,分析了双圆柱桥墩在接触与非接触爆炸荷载作用下的破坏特征、损伤程度及动力响应。结果表明:因试验药量以及构件尺寸的变化,实桥桥墩破坏模式由模型试验时局部冲切破坏模式转变为受弯破坏模式,但破口处伴随局部受压裂缝与斜剪裂缝,且横、竖向破损尺度与对应方向上的截面刚度相关;此外,破口处的钢筋屈服后形态特征与常规受弯破坏存在差异;与接触爆炸相比,非接触爆炸的能量耗散更快,相同药量时破坏程度明显更小。由于实桥构件尺度较大,墩身迎爆面对冲击波的阻挡作用明显,进行实桥墩身抗爆分析时绕射波的影响可以忽略,但必须考虑桥下空间的约束效应与地面和护坡等构造物对冲击波的反射作用。在墩柱结构的抗爆设计及简化分析时,双柱墩纵桥向可简化为一端固结一端铰支的结构,横桥向可简化为两端固结的结构。To study the blast resistance of reinforced concrete(RC)bridge piers when subjected to explosive loads,this study conducted an field test on a three-span simply supported bridge featuring circular-section double-column piers.The analysis focused on the failure characteristics,damage level,and dynamic response of the double-column piers with circular-section subjected to both in-contact and non-contact explosive loads.The findings indicate that the failure mode of the bridge piers might shift from a local shearing failure mode to a bending failure mode due to variations in explosive equivalent and structural dimensions.Nevertheless,the extent of rupture in transversal and vertical directions is found to be dependent on the sectional stiffness in the corresponding directions,entailing local compressive and inclined shear cracks.In addition,the reinforcement shape after yielding at the location of rupture deviate from those observed in conventional bending failure.Compared to contact explosions,non-contact explosions result in significantly less damage at the equivalent of explosive mass due to the faster dissipation of energy.The diffraction effect of the shockwave,which is attributed to the large dimensions of the bridge columns and their large energy consumption capacities in the blast-facing surface,can be neglected in the anti-blast analysis of pier bodies.However,the confinement effect in the space beneath the bridge and the reflection of the ground and embankment must be taken into account in the analysis.For simplified design and analysis,double-column piers can be modeled longitudinally as pin supports at the top with two fixed ends when conducting transversal analysis.

关 键 词：桥梁工程 钢筋混凝土桥墩 实桥爆炸 破坏模式 动力响应 简化分析 

分 类 号：U446.1[建筑科学—桥梁与隧道工程]