钢纤维增强氧化镁混凝土的变形与抗压强度

Deformation and Compressive Strength of Steel Fiber Reinforced MgO Concrete.

作者信息

Jiang Feifei, Mao Zhongyang, Deng Min, Li Dawang

机构信息

State Key Laboratory of Materials-Oriented Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211800, China.

College of Naval Architecture Civil Engineering, Jiangsu University of Science and Technology, Zhangjiagang Campus, Suzhou 215600, China.

出版信息

Materials (Basel). 2019 Nov 4;12(21):3617. doi: 10.3390/ma12213617.

DOI:10.3390/ma12213617

PMID:31689933

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6862612/

Abstract

To reduce the cracking caused by shrinkage and avoid the brittle behavior of concrete, MgO expansion agent and steel fibers were used in this paper. Firstly, the effect of MgO and steel fibers on the compressive strength of concrete was compared. The results showed that the compressive strength of steel fibers reinforced concrete (SC) and steel fiber reinforced MgO concrete (SMC) was significantly improved. Compared with ordinary concrete (OC), SMC's 28 days compressive strength increased by 19.8%. Secondly, the influence of MgO and steel fibers with different contents on the self-volumetric deformation of concrete was compared through the experiment. The results showed that as a result of the hydration expansion of MgO, MC and SMC both showed obvious expansion, and their 190 days expansion was 335 μ ε and 288 μ ε , respectively. Lastly, through a scanning electron microscope (SEM) test, it was found that the constraint effect of steel fibers changed the expansion mode of MgO from outward expansion to inward extrusion, thus improving the interfacial bond strength of concrete.

摘要

为减少收缩引起的开裂并避免混凝土的脆性，本文使用了氧化镁膨胀剂和钢纤维。首先，比较了氧化镁和钢纤维对混凝土抗压强度的影响。结果表明，钢纤维增强混凝土（SC）和钢纤维增强氧化镁混凝土（SMC）的抗压强度显著提高。与普通混凝土（OC）相比，SMC的28天抗压强度提高了19.8%。其次，通过试验比较了不同含量的氧化镁和钢纤维对混凝土自体积变形的影响。结果表明，由于氧化镁的水化膨胀，MC和SMC均表现出明显的膨胀，其190天的膨胀量分别为335με和288με。最后，通过扫描电子显微镜（SEM）试验发现，钢纤维的约束作用使氧化镁的膨胀模式从向外膨胀变为向内挤压，从而提高了混凝土的界面粘结强度。