摘要
超高韧性水泥基复合材料(UHTCC)具有超高的延性、优异的能量吸收能力以及良好的耐久性,其在防护结构中有着广泛的应用前景。K&C模型被用于研究混凝土类准脆性材料在动态荷载作用下动力特性,但是该模型无法准确地描述UHTCC这种韧性水泥基材料的各项动态力学特性。为得到适用于UHTCC的K&C模型参数,基于现有UHTCC材料单轴压缩/拉伸、霍普金森杆的压缩/劈裂和三轴压缩试验数据,校核K&C模型中的损伤参数、应变率效应参数以及强度面参数,并采用改进后的K&C模型参数模拟UHTCC靶体在接触爆炸荷载下的动态响应。模拟结果表明:采用改进后的K&C模型参数对爆炸荷载下UHTCC靶板迎爆面的开坑尺寸预测结果与相应文献中的试验结果基本一致,相差在6%以内。同时,改进的K&C模型参数相较于其他K&C模型参数可以更为准确地预测UHTCC靶板在爆炸荷载作用下的损伤分布和破坏形态。为了进一步验证改进的K&C模型参数的准确性,利用LS-DYNA软件预测了弹体高速冲击UHTCC靶体时弹体的侵彻深度和靶体的迎弹面开坑直径,发现模拟结果与文献中的试验结果较为吻合。
The ultra-high toughness cementitious composite(UHTCC) has ultra-high ductility, excellent energy absorption capacity, and good durability. These characteristics allow it to have a wide variety of applications in several protective structures. The well-known K&C model is used for concrete-like materials to study their behavior under dynamic load, but it cannot accurately describe the dynamic mechanical properties of UHTCC, a tough cement-based material. To obtain the K&C model parameters suitable for UHTCC, the present paper was based on the existing UHTCC uniaxial compression/tension, compression/tension of Split Hopkinson Pressure Bar(SHPB), and triaxial compression test data to calibrate the damage parameters, strain rate effect parameters and strength surface parameters in the K&C model for UHTCC. Then, the improved K&C model parameters were used to simulate the dynamic response of the UHTCC target subject to the contact explosion loads. The simulation results show that the improved K&C model parameters predict the cratering size on the front surface of the UHTCC plate under the explosion load, which is consistent with the test results in the corresponding literature, and the error is kept within 6%. At the same time, compared with other K&C model parameters, the improved K&C model parameters in this paper can more accurately predict the damage distribution and failure form of the UHTCC plate subjected to explosive load. To further verify the accuracy of the improved K&C model parameters in the present paper, the LS-DYNA software was used to predict the penetration depth of the projectile and the crater diameter of the target subject to the projectile impacts UHTCC at a high speed. The penetration depth and crater diameter are in good agreement with the test results in the literature.
作者
徐世烺
吴平
李庆华
周飞
李锐
XU Shilang;WU Ping;LI Qinghua;ZHOU Fei;LI Rui(Institute of Advanced Structures,Zhejiang University,Hangzhou 310058,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2022年第6期233-244,256,共13页
Journal of Building Structures
基金
国家自然科学基金项目(51622811,51678522)。
