摘要
为了研究动荷载作用下不同围压水平对类岩材料混凝土力学特性的影响。从混凝土细观结构出发,建立混凝土随机骨料塑性损伤模型,根据混凝土破坏强度的数值试验确定方法,施加冲击荷载,计算了不同围压水平下混凝土的破坏强度和破坏位移,分析了不同围压水平下的破坏形态。结果表明:混凝土属于围压敏感性材料,加载速率不变,随着围压的不断增大,混凝土的动强度、破坏位移以及残余强度也在不断提高,两者成线性增长关系;围压不变,随着加载速率的提高,混凝土的动强度和破坏位移非线性提高,残余强度基本不变。围压大小不同,混凝土材料内部应力分布不同,导致混凝土的破坏类型发生变化,反映出破坏面形状和大小不同。该模型可以比较好的模拟围压作用下混凝土的动力特性。
In order to study the influence of different confining pressure on mechanical properties of concrete under dynamic loading. From the microscopic structure of concrete, establishes concrete random aggregate plastic damage model.According to the numerical test method for determining the breaking strength of the concrete,calculate the breaking strength and damage displacement and analysis of failure modes under different confining pressure levels.Results show that the concrete belongs to confining pressure sensitive material. Loading rate unchanged,with the confining pressure is increasing, the dynamic strength of concrete, damage displacement and residual strength is improving,both a linear growth relationship.Confining pressure unchanged,with the increase of loading rate,the dynamic strength of concrete and damage displacement nonlinear improved, the residual strength basically unchanged.The concrete materials with different internal stress distribution under different confining pressure which will change the damage type of concrete.Reflect the different shapes and sizes failure surface.The model can better simulate the dynamic characteristics of concrete under confining pressure.
出处
《混凝土》
CAS
北大核心
2017年第12期22-25,28,共5页
Concrete
基金
国家科技支撑计划项目(2014BAL01B03)
关键词
类岩材料
动态荷载
围压
力学特性
rock like material
dynamic load
confining pressure
mechanical property
