摘要
膨胀性是影响压浆料硬化后力学性能,决定预应力筋与预制混凝土能否协同作用的关键技术参数。主要研究了CSA膨胀剂对压浆料膨胀率、流动性及力学性能的影响,结合扫描电镜及孔结构分析,探究其微观机理。结果表明:随CSA膨胀剂掺量增加,压浆料24 h自由膨胀率逐渐增大;CSA膨胀剂掺量为6.8%时,浆体流动性最佳,初始、30 min、60 min流动度分别为14.9、17.2、18.9 s;CSA膨胀剂掺量为3.4%时,28 d抗压强度最高,为77.9 MPa;CSA膨胀剂在水泥水化硬化中后期生成钙矾石等晶体,填充于孔隙内,细化孔径,改善孔结构,提高硬化浆体强度。
The expansion property is the key technical parameter that affects the mechanical properties of the grouting materials after hardening and determines whether the prestressed tendon and the precast concrete can work synergistically.In this paper,the effects of CSA expansion agent on the expansion rate,fluidity and mechanical properties of the grouting materials were studied.The microscopic mechanism was explored by scanning electron microscopy and pore structure analysis.The results show that with the increase of CSA expansion agent,the 24 h free expansion rate of the grouting materials was gradually increased.When the CSA expansion agent was 6.8%,the slurry fluidity was the best,the initial,30 min,60 min fluidity was 14.9 s,17.2 s,18.9 s;when the dosage was 3.4%,the 28 d compressive strength reached the maximum,which was 77.9 MPa;CSA expansion agent forms crystals such as ettringite in the middle and late stage of cement hydration hardening,filled in the pores and refined the pore diameter,improved the pore structure and increased the strength of the hardened slurry.
作者
史艳娜
SHI Yanna(Fujian Prominent Science New Materials Co.Ltd.,Xiamen 361100,China)
出处
《新型建筑材料》
北大核心
2020年第11期134-137,共4页
New Building Materials
关键词
压浆料
CSA膨胀剂
流动度
力学性能
pressure slurry
CSA expansion agent
fluidity
mechanical properties