爆炸荷载下钢管混凝土墩柱的动力响应研究  

DYNAMIC RESPONSE OF CONCRETE-FILLED STEEL TUBE PIERS UNDER BLAST LOADINGS

作　　者：孙珊珊[1] 赵均海[1] 贺拴海[2] 崔莹[3] 刘岩[1] SUN Shan-shan;ZHAO Jun-hai;HE Shuan-hai;CUI Ying;LIU Yan(School of Civil Engineering, Chang’an University, Xi’an, Shaanxi 710061, China;School of Highway, Chang’an University, Xi’an, Shaanxi 710064, China;School of Mechanical Engineering, Xi’an Shiyou University, Xi’an, Shaanxi 710065, China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061 [2]长安大学公路学院,陕西西安710064 [3]西安石油大学机械工程学院,陕西西安710065

出　　处：《工程力学》2018年第5期27-35,74,共10页Engineering Mechanics

基　　金：高等学校博士学科点专项科研基金项目(20110205130001);中国博士后科学基金面上项目(2015M580803);中央高校基本科研业务费专项资金项目(310828173402;310828171012;310828171003)

摘　　要：设计并制作了3根普通钢管混凝土墩柱和1根复式中空钢管混凝土墩柱,进行了TNT药量分别为3 kg和50 kg的3发4工况静爆试验,获得构件的迎爆面及背爆面的柱面超压分布、残余变形以及最终破坏形态,结合有限元分析,研究了爆炸荷载下钢管混凝土墩柱的动态响应、破坏模态及参数影响。研究表明:50 kg TNT作用下、比例距离为0.14 m/kg1/3时,外径同为273 mm、壁厚为7 mm的普通钢管混凝土墩柱抵抗爆炸荷载的变形能力优于中空钢管内径为50 mm、壁厚为4 mm的复式钢管混凝土墩柱;基于试验结果建立了多物质流固耦合的数值模拟方法,可有效模拟钢管混凝土墩柱在爆炸荷载下的动态响应;钢管混凝土墩柱三种典型破坏形态分别是:低超压峰值-高持时发生弯曲破坏、高超压峰值-低持时发生剪切破坏及介于两种情况之间的弯剪破坏;炸药当量为50 kg,比例距离z>0.3 m/kg1/3时,爆炸荷载下试件柱的残余变形可忽略不计;核心混凝土强度等级的增强以及含钢率的提高,可有效降低柱中点水平残余变形;提高钢管屈服强度,可降低柱中残余变形,当钢材强度等级≥345 MPa时,继续增大屈服强度对提高钢管混凝土墩柱的抗爆性能意义不大。Explosion experiments of three concrete-filled steel tube piers and one composite concrete-filled steel tube piers under different charge were deployed, with a TNT charge being 3 kg and 50 kg, respectively. The cylinder overpressure distribution, residual deformation and failure pattern were obtained. With the finite element analysis, the dynamic response, failure mode and parameter influence of concrete-filled steel tube piers under blast load were studied. The results show that compared with the composite concrete-filled steel tube piers of 50 mm core steel tube diameter and 4 mm thickness, the ordinary ones are better at resisting deformation while the outer diameter is 273 mm, the TNT charge is 50 kg and the scale distance is 0.14 m/kg1/3. Based on the experimental results, multi-material flow-solid coupling simulation method was established, which effectively simulated the dynamic response of the concrete filled steel tube piers under explosion loads. Typical destruction paradigm can be categorized into flexural damage under low peak overpressure-long duration blast loading, shear fracture under high peak overpressure-short duration blast loading and bending-shear failure between the above two cases. Residual deformation is negligible when the scale distance is more than 0.3 m/kg1/3 and the explosive charge is 50 kg. Enhancing the core concrete＇s strength grade and enlarging the steel ratio can effectively bring down the residual deformation. Increasing the yield strength can reduce the residual deformation, however with little significance when the yield strength is greater than or equal to 345 MPa.

关 键 词：钢管混凝土墩柱 静爆试验 抗爆性能 残余变形 流固耦合 

分 类 号：TU398.9[建筑科学—结构工程]