摘要
畸形骨料对混凝土物理力学特性的影响是有待研究问题之一。基于内聚力模型,选取混凝土合理的本构关系与模型网格精度,利用现有试验结果对模型参数进行校调,完成细观层次下混凝土二维内聚力模型的建立,并以畸形骨料的长宽比Ck、占比Zb和级配Jp三个参数为变量,向二级配混凝土中掺入一定比例的畸形骨料,建立不同的细观模型方案进行含畸形骨料混凝土单轴受压模拟。结果表明:采用内聚力模型能有效地分析确定混凝土等多相复合材料的力学性能,并可以跟踪和分析材料的破坏过程。含畸形骨料混凝土单轴受压时,破碎骨料主要是畸形骨料,优质骨料出现破碎很少;畸形骨料占比越高,发生破碎的可能性就会越大;相较大级配的畸形骨料,小级配的畸形骨料更容易破碎;对二级配含畸形骨料混凝土而言:畸形骨料长宽比Ck越大、占比Zb越高、级配Jp越大时,混凝土的抗压强度越低。
The influence of deformed aggregate on the physical and mechanical properties of concrete is one of the problems to be solved.Based on the cohesive zone model,the reasonable constitutive relationship and model grid accuracy of concrete are selected.The existing test results are used to adjust the model parameters,and the concrete two-dimensional cohesion model under the meso-level was established.Taking three parameters of the length and width ratio Ck,the proportion Zb and the gradation Jp of the deformed aggregate as variables,a certain proportion of deformed aggregate was added into the secondary concrete.Different meso-model schemes are established to simulate the uniaxial compression of concrete with deformed aggregate.The results show that the cohesive zone model can effectively analyze and determine the mechanical properties of concrete and other multiphase composite materials.Track and analyze of the failure process of materials can be conducted.When concrete containing deformed aggregate is under uniaxial compression,the broken aggregate is mainly deformed aggregate,and the high quality aggregate is rarely broken;The higher the proportion of deformed aggregate,the greater the possibility of crushing;Compared with large graded deformed aggregate,small graded deformed aggregate is more easily broken;For the two-graded concrete with deformed aggregate;the larger the ratio of length and width of deformed aggregate Ck,the higher the proportion of Zb and the larger the gradation of Jp are,the lower the compressive strength of concrete will be.
作者
田羽
张小飞
吴健
肖天培
覃培
TIAN Yu;ZHANG Xiaofei;WU Jian;XIAO Tianpei;QIN Pei(College of Civil Engineering and Architecture of Guangxi University,Nanning 530004,China;Beijing Engineering CO.LTD.,Beijing 100000,China)
出处
《河南水利与南水北调》
2021年第8期69-73,共5页
Henan Water Resources & South-to-North Water Diversion
基金
国家自然科学基金项目(51809051)。
关键词
混凝土
内聚力模型
畸形骨科
抗压强度
concrete
cohesive zone model
deformed aggregate
compressive strength
作者简介
通讯作者:张小飞(1964-),男,教授级高级工程师,主要从事水工结构研究。
