摘要
为研究橡胶混凝土弯折裂纹扩展过程和破坏机理,配制了水灰比为0.35、0.4、0.45、橡胶掺量为0、10%、20%、30%的橡胶混凝土,进行抗折强度试验,得到3种水灰比、4种橡胶掺量的混凝土抗折强度变化规律。基于细观层次,将橡胶混凝土看作由砂浆、粗骨料、橡胶颗粒、砂浆-粗骨料界面和砂浆-橡胶颗粒界面组成的多相复合材料。建立橡胶混凝土细观数值模型,模拟不同橡胶掺量和不同水灰比的橡胶混凝土抗折强度试验。结果表明:砂浆-橡胶颗粒的界面区域对橡胶混凝土抗折强度和破坏过程影响较大;随着水灰比的增大,橡胶-砂浆界面的强度与砂浆的强度差值减小,使橡胶混凝土抗折强度减小趋势变得缓和;随着橡胶掺量增大,增加了裂纹发展的不确定性,减弱了混凝土的脆性破坏。
In order to study the propagation process and failure mechanism of the bending crack of concrete,rubber concrete with water cement ratio of respectively 0.35,0.4 and 0.45 and rubber content of respectively 0,10%,20%and 30%was prepared to conduct bending strength test.The change rule of bending strength of concrete with 3 kinds of water cement ratios and 4 kinds of rubber contents was obtained.In the mesoscopic level,rubber concrete can be regarded as a multiphase composite material composed of mortar,coarse aggregate,rubber particles,mortar-coarse aggregate interface and mortar-rubber particle interface.The mesoscopic numerical model of rubber concrete was built to simulate the bending strength test of rubber concrete with different rubber contents and water cement ratios.The results showed that the interface area between mortar and rubber particles has a great impact on the bending strength and failure process of rubber concrete.With the increase of water cement ratio,the difference between the strength of rubber-mortar interface and that of mortar decreases,thereby alleviating the decreasing trend of the bending strength of rubber concrete.With the increase of rubber content,the uncertainty of crack development is increased and the brittle failure of concrete is weakened.
作者
薛刚
孙立所
侯玮华
董伟
XUE Gang;SUN Lisuo;HOU Weihua;DONG Wei(School of Civil Engineering,University of Inner Mongolia Science and Technology,Baotou 014010,China)
出处
《混凝土》
CAS
北大核心
2021年第7期43-47,共5页
Concrete
基金
国家自然科学基金资助项目(51868063)。
关键词
橡胶混凝土
抗折强度
细观
数值模拟
rubber concrete
flexural strength
mesoscopic
numerical simulation
