摘要
混凝土动态强度的增强效应DIF(dynamic increase factor)一般由混凝土霍普金森杆SHPB(split Hopkinson pressure bar)试验进行测量,而基于不同应变率ε条件下的试块尺度的SHPB试验结果得到的宏观DIF-ε关系不能直接应用于数值模型定义。运用ANSYS/LS-DYNA有限元软件和K&C混凝土模型,对混凝土SHPB直接拉伸、劈裂和层裂试验进行了模拟研究。提出了局部和非局部损伤模型中引入网格和应变率ε双修正的DIF-ε模拟方案,并对混凝土非局部损伤模型中非局部特征长度L在数值模拟中的应用方案进行了讨论。SHPB和混凝土梁冲击试验模拟研究和试验数据的比较结果均表明,提出的分别基于局部和非局部损伤混凝土模型的双修正DIF-ε模拟方案能够较为准确描述混凝土动态力学行为。
The dynamic increasing factor(DIF)of concrete is normally measured via split Hopkinson pressure bar(SHPB)tests.However,the tested macro-scale DIF-ε relationship from the specific SHPB test specimens under different strain rates εcannot be directly introduced to finite element(FE)modelling.Based on the ANSYS/LS-DYNA and K&C concrete damage model,the SHPB direct tension,split and spalling tests were modelled,and a modified DIF-εrelationship with both mesh and ε corrections for dynamic mechanic behaviour of concrete material was proposed for local and non-local damage modelling of concrete respectively,also the numerical application of the nonlocal characteristic length L was detailed discussed.The comparison between the SHPB/impact test modelling and the relevant test results indicated that the proposed doubly corrected DIF-ε numerical application schemes could properly capture the concrete dynamic mechanical property.
作者
李晓琴
廖俊智
陈建飞
陆勇
陈前均
LI Xiao-qin;LIAO Jun-zhi;CHEN Jian-fei;LU Yong;CHEN Qian-jun(Faculty of Civil Engineering,Kunming University of Science and Technology,Kunming,Yunnan 650500,China;Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong 518055,China;Institute for Infrastructure and Environment,School of Engineering,University of Edinburgh,Edinburgh EH93JL,UK;Institute of Subsurface Energy System,TU Clausthal,Clausthal-Zellerfeld 38678,Germany)
出处
《工程力学》
EI
CSCD
北大核心
2024年第12期42-51,共10页
Engineering Mechanics
基金
国家自然科学基金项目(52168029,51968035)
云南省万人计划青年拔尖人才项目(云人社通[2020]150号YNWR-QNBJ-2020-049)。
