Q420钢管大气腐蚀后的抗侧撞性能  

Lateral impact resistance of Q420 steel tubes after atmospheric corrosion

作　　者：旷金鑫 张春涛[1,2] 郝志明 李洪祥[3] KUANG Jinxin;ZHANG Chuntao;HAO Zhiming;LI Hongxiang(School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province,School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Institute of Systems Engineering,China Academy of Engineering Physics,Mianyang 621999,Sichuan,China)

机构地区：[1]西南科技大学土木工程与建筑学院,四川绵阳621010 [2]西南科技大学土木工程与建筑学院工程材料与结构冲击振动四川省重点实验室,四川绵阳621010 [3]中国工程物理研究院总体工程研究所,四川绵阳621999

出　　处：《爆炸与冲击》2021年第2期143-153,共11页Explosion and Shock Waves

基　　金：国家自然科学基金(51508482,51568058);西藏自治区科技计划(CGZH2018000014)。

摘　　要：为研究大气腐蚀对Q420钢管构件服役期内耐撞性的影响,提出了计及腐蚀损伤的材料模型。引入损伤因子(ω)修正Voce模型,推导随腐蚀程度变化的低合金钢材本构方程,并通过加速腐蚀试验结果回归相应参数。利用ABAQUS软件定义构件材料特性,建立起受腐蚀的Q420钢管仿真模型,采用显式动力算法分析多种初始状态下,撞击体与不同腐蚀程度钢管的冲击响应规律。开展预腐蚀Q420钢管的落锤试验,将试验结果与数值计算结果进行对比,验证所建模型的合理性。结果表明:大气腐蚀导致材料名义强度降低,对Q420钢管抗撞击能力影响显著;随着腐蚀程度增加,冲击力峰值减小,撞击时间和深度增加;Q420钢管受腐蚀后抗冲击刚度减小,构件整体变形耗能增加,表明大气腐蚀使其抗冲击性能下降;同等动能增量下,增大撞击体初速度比增加初始质量获得的冲击力峰值增幅更大,而所得到的接触时间增幅更小。Q420 circular steel tubes are widely used to build large-scale steel structures.Such buildings serving in mountain areas are subject to atmospheric corrosion and impact load.In order to study the effect of atmospheric corrosion on the crashworthiness of Q420 steel tube members during service,a material model considering corrosion damage was proposed which treated corrosion damage as a change in material parameters.Specifically,a damage factorωwas introduced to modify the Voce constitutive equation based on the one-dimensional damage theory.A constitutive equation for low alloy steel varied with the degree of corrosion was deduced,these model parameters were determined through accelerated corrosion test that used acidic solution to accelerate steel corrosion and used static force to stretch the specimens.Based on the proposed constitutive method,relevant material properties were defined by utilizing the ABAQUS software to establish the finite element model of the Q420 steel tubes.A number of 0.84 meters long Q420 steel tube member models within different degrees of corrosion were developed,and these pipes were impacted at their mid-span by a flat-headed impactor with a certain mass and initial velocity.An explicit dynamic algorithm has been used for the simulation to analyze impact response law of rigid impactor and corroded steel pipes under various initial conditions.In addition,a series of impact tests were conducted to compare the behaviour of pre-corroded Q420 steel tubes subjected to lateral impact by drop hammers falling through changing initial height.The weight loss of pipes respectively was 0%,10%,20%,30%and 40%,and the speed of moving hammers was 4.00,5.79 and 7.43 m/s.Steel tube specimens were subjected to a constant axial pressure,without considering the effect of the axial force on test results.Numerical results were compared with test results to verify the rationality of the established models.According to numerical and experimental results,it demonstrates that atmospheric corrosion leads to a decr

关 键 词：Q420钢管 大气腐蚀 耐撞性 本构方程 落锤试验 

分 类 号：O347[理学—固体力学]