MgO钢纤维混凝土单轴受压应力-应变全曲线的试验研究  

Experimental study on uniaxial compressive stress-strain curve of MgO-steel fiber concrete

作　　者：姜竹昌 江飞飞 邓敏[2] 曹洪亮 尹永胜 JIANG Zhuchang;JIANG Feifei;DENG Min;CAO Hongliang;YIN Yongsheng(Shandong High-Speed Gaoguang Highway Co. Ltd., Dongying 257300, China;State Key Laboralory of Materials-Oriented Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211800, China)

机构地区：[1]山东高速高广公路有限公司,山东东营257300 [2]南京工业大学材料科学与工程学院材料化学工程国家重点实验室,江苏南京211800

出　　处：《南京工业大学学报（自然科学版）》2020年第6期760-765,共6页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：山东省交通运输科技计划(2018B3702)。

摘　　要：采用单轴压缩试验,进行了MgO钢纤维混凝土单轴受压应力应变全曲线研究,分析不同掺量的MgO和钢纤维的复合作用对混凝土全曲线本构参数的影响规律。结果表明:单掺8%MgO混凝土的峰值应力比普通混凝土提高了4.8%,但砂浆孔隙率增加了6.7%,韧性指数降低了22.5%,不适合用于承受冲击荷载的结构中;单掺1%钢纤维后,混凝土性能有了一定程度的增强,强度和韧性指数分别提高了6.1%和17.8%;复掺8%MgO和1%钢纤产生了“超叠加”效应,进一步提高了混凝土性能,峰值应力比普通混凝土提高了17.0%,韧性指数提高了35.2%,孔隙率减小了31.6%,能有效避免结构的无明显特征的脆性破坏,适用于对混凝土强度和韧性要求较高的结构。The stress-strain full curve of MgO-steel fiber concrete under uniaxial compression was studied by uniaxial compressive tests,and the influence law of composite action of different content of MgO and steel fiber on the constitutive parameters of concrete under full curve was analyzed.Results showed that the peak stress of concrete with 8%MgO was 4.8%higher than that of ordinary concrete,but the porosity of mortar was 6.7%higher,while the toughness index was 22.5%lower,which was not suitable for the structure under impact load.When 1%steel fiber was added to concrete,the strength and toughness indexs of concrete were increased by 6.1%and 17.8%,respectively.Concrete mixed with 8%MgO and 1%steel fiber could produce"super superposition"effect,which further improved the performance of concrete.The peak stress was 17.0%higher than that of ordinary concrete,the toughness index was 35.2%higher,and the porosity was 31.6%lower.In this way,the brittle failure without obvious characteristics of structure could be effectively avoided,which was suitable for the structure of high requirements for concrete strength and toughness.

关 键 词：MGO混凝土 钢纤维混凝土 复掺 应力应变全曲线 孔隙率 界面性能 

分 类 号：TU528[建筑科学—建筑技术科学]