【作者】 李东；

【导师】 魏德敏；

【作者基本信息】 华南理工大学 ， 防灾减灾工程及防护工程， 2020， 博士

【摘要】 无机玻璃材料应用极为广泛,尤其是在土木建筑行业与汽车行业。在冲击荷载作用下,无机玻璃材料破碎后产生的碎片,对人们的生命财产安全有很大的威胁。因此有必要研究无机玻璃材料和构件在冲击荷载下的破坏过程,用于预测玻璃在冲击下的破坏程度或者指导玻璃结构或者构件的设计依据。本文研究了低速和高速冲击下单层玻璃板的破坏过程、低速冲击下夹层玻璃板的破坏过程。对于低速冲击下单层玻璃圆板的破坏过程研究,采用了率相关内聚力模型进行结构响应的数值计算。对于高速侧向冲击下玻璃方板的损毁过程研究,采用了改进的TCK本构模型,使其能够同时分析拉伸单元和压缩单元在任意非零应变率下的损伤。对于低速冲击下夹层玻璃板的破坏过程研究,根据不同厚度夹层玻璃板的系列落锤试验,归纳得到夹层玻璃板弯曲失效的三阶段破坏模型,并采用TCK-JH2组合本构模型进行了破坏过程的分析。本文的主要研究工作如下:(1)通过无机玻璃材料的霍普金森压杆试验与动态劈裂试验模拟,研究了无机玻璃材料的冲击力学性能。霍普金森压杆试验中,考虑了惯性效应、摩擦与试样形状对试验结果的影响。动态劈裂试验中,通过修正JH2参数提高了数值试验的精度。对直接加载法、柔性垫块法、刚性垫块法与平台处理法四种加载方式进行了对比分析,由此提出了柔性垫块法的修正系数。(2)建立了可描述无机玻璃材料脆性断裂的率相关内聚力模型(RDCZM),在此基础上研究了受低速冲击单层玻璃圆板的破坏过程,并将数值计算结果与试验结果进行了对比验证。(3)改进了TCK本构模型,使其能同时分析压缩单元及拉伸单元在任意非零应变率下的损伤,进而研究了高速侧向冲击下玻璃方板的损伤区域形状与大小、损伤扩展过程以及应力波传播过程。侧向冲击试验的数值模拟结果与相关试验结果进行了对比验证,并分析了本文冲击损伤扩展及应力波传播过程的计算精度。(4)研究了低速冲击下夹层玻璃板的破坏过程,发现两种基本的失效模式:冲切失效模式和弯曲失效模式。对几种厚度的夹层玻璃板进行了不同冲击速度的落锤试验,进而提出夹层玻璃板在低速冲击下弯曲失效的三阶段破坏模型,并给出划分不同破坏阶段的理论依据。(5)建立了无机玻璃材料的TCK-JH2组合本构模型,对其恢复刚度、积分精度等因素进行了研究并应用于夹层玻璃板的低速冲击下弯曲失效的响应计算,计算结果与相关试验结果进行了对比验证。进一步研究发现了临界体积应变与夹层材料刚度等参数的对夹层玻璃板抗冲击能力影响。更多还原

【Abstract】 Soda-lime glass materials are widely used,especially in civil construction industry and automobile industry.Under impact loads,the broken fragments of soda-lime glass materials have a great threat to people’s life and property.Therefore,it is necessary to study the breakage process of soda-lime glass materials and components under impact loads,to predict the damage degree of glass under the impact or to guide the design basis of glass structure or components.In this paper,the failure process of single-layer glass plate and laminated glass plate under lowspeed and high-speed impact are studied.For the study of the failure process of single-layer glass circular plate under low-speed impact,the rate-dependent cohesive zone model is used to calculate the structural response.For the study of the damage process of square glass plate under high-speed edge-on impact,the improved TCK constitutive model is used to analyze the damage of tension element and compression element at the same time at any non-zero strain rate.According to a series of drop weight tests of laminated glass plates with different thickness,a three-stage failure model of laminated glass plates was concluded,and the failure process was analyzed by TCK-JH2 combined constitutive model.The main research work of this paper is as follows:(1)The impact mechanical properties of soda-lime glass materials were studied by Hopkinson pressure bar test and dynamic split test numerically.In the Hopkinson bar test,the effects of inertia,friction and specimen shape on the test results are considered.In the dynamic splitting test,the accuracy of numerical test is improved by modifying JH2 parameters.The direct loading method,the soft strip method,the rigid strip method and the flatten specimen method are compared and analyzed,and the correction coefficient of the soft strip method is proposed.(2)A rate-dependent cohesive zone model(RDCZM)was established to describe the brittle fracture of soda-lime glass materials.On this basis,the failure process of single-layer glass circular plate impacted by low velocity was studied,and the numerical calculation results were compared with the test results.(3)The TCK constitutive model is improved so that it can analyze the damage of compression element and tension element at the same time at any non-zero strain rate.Then the shape and size of damage area,damage propagation process and stress wave propagation process of square glass plate under high-speed edge-on impact are studied.The numerical simulation results of the edge-on impact test are compared with the relevant test results,and the calculation accuracy of the damage propagation and stress wave propagation process in this paper is analyzed.(4)The failure process of laminated glass under low speed impact is studied.Two basic failure modes are summarized: punching failure mode and bending failure mode.A three-stage failure model of laminated glass plate under low-speed impact is proposed,and the theoretical basis for dividing different failure stages is given.(5)The restoring stiffness and integration accuracy of TCK-JH2 composite constitutive model of soda-lime glass materials are studied and applied to the low-speed impact response calculation of laminated glass plate.The calculation results are compared with the relevant test results.Furthermore,it is found that the critical volume strain and the stiffness of the interlayer material affect the impact resistance of the laminated glass plate.更多还原