建筑结构化爆作用级数型荷载动力系数研究  

Dynamic coefficient of series chemical blast load in building structure

作　　者：刘榕 耿少波[2] 贺耀北 LIU Rong;GENG Shaobo;HE Yaobei(Hunan Provincial Communications Planning,Survey&Design Institute Co.,Ltd.,Changsha 410200,China;Department of Civil Engineering,North University of China,Taiyuan 030051,China;College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南省交通规划勘察设计院有限公司,长沙410200 [2]中北大学土木工程学科部,太原030051 [3]湖南大学土木工程学院,长沙410082

出　　处：《振动与冲击》2021年第23期51-57,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51408558);湖南省科技重大专项(2017SK1010)。

摘　　要：鉴于现行结构抗爆设计规范中采用简化的线性衰减爆炸荷载模式,其等效作用时长小于爆炸荷载真实作用时长。以等冲量、等超压峰值为条件,采用级数型爆炸荷载模式,建立真实作用时长与等效作用时长关系,求解结构弹塑性振动微分方程,推导出一三次项、二三次项两种级数型爆炸荷载等效静载动力系数。结合现行规范中简化的动力系数对比,通过典型工况计算算例表明:整体上,级数型爆炸荷载比等冲量线性爆炸荷载求出的动力系数数值低;当延性比β<2.5且结构荷载参数θ_(i)<1.2时,级数型爆炸荷载与等冲量线性爆炸荷载动力系数差异小于2%,可直接采用规范简化公式;当β<2.5且θ_(i)≥1.2时,一三次项级数型爆炸荷载动力系数整体偏小;当β≥2.5且θ_(i)<1.2时,一三次项与二三次项级数型爆炸荷载动力系数差异可忽略,两者与规范简化公式差异在8%以上;当β≥2.5且θ_(i)≥1.2时,动力系数与衰减曲线波形系数a及级数荷载类型相关性较高。Due to adopting the simplified linear attenuation blast load mode in the current code of structure anti-explosion design,the equivalent action duration of blast load is smaller than its real action duration.Here,the relation between the real action duration and the equivalent one was established by using the series blast load model under conditions of equal impulse and equal overpressure peak value.The differential equation of elastic-plastic vibration for a structure was solved,and the equivalent static load dynamic coefficients for two series blast loads with 1-3 power terms and 2-3 power terms were derived.Compared with the simplified dynamic coefficient in current code,some calculation examples under typical working conditions showed that as a whole,the dynamic coefficient of series blast load is lower than that of linear blast load with equal impulse;when ductility ratioβ<2.5 and structural load parameter θ_(i)<1.2,the difference between dynamic coefficients of series blast load and linear blast load with equal impulse is less than 2%,and the simplified formula in current code can be directly adopted;whenβ<2.5 and θ_(i)≥1.2,the dynamic coefficient of series blast load with 1-3 power terms is totally smaller;whenβ≥2.5 and θ_(i)<1.2,the difference between dynamic coefficients of series blast load with 1-3 power terms and that with 2-3 power terms can be ignored,and the difference between dynamic coefficients of series blast loads and that obtained with the simplified formula in current code is more than 8%;whenβ≥2.5 and θ_(i)≥1.2,the correlation among dynamic coefficient,waveform coefficient a of attenuation curve and type of series blast load is higher.

关 键 词：常规武器 爆炸荷载 动力系数 延性比 作用时长 

分 类 号：TU352.13[建筑科学—结构工程] TU313.2