掺杂EVA胶粉的硫铝酸盐-硅酸盐复合防腐砂浆制备及性能研究

Study on Preparation and Properties of Sulphoaluminate Silicate Anticorrosive Mortar Doped with EVA Rubber Powder

本文以PO 52.5硅酸盐水泥、42.5硫铝酸盐水泥、Ⅱ级粉煤灰、粒径为0.30~0.60 mm砂、乙烯/醋酸乙烯酯共聚物胶粉(EVA)、羟丙基甲基纤维素(HPMC)、粉末聚羧酸减水剂(PCL)、醚类粉状消泡剂(XP)为主要原料,通过物理共混制备了EVA胶粉改性硫铝酸盐-硅酸盐复合防腐砂浆,并分析了EVA不同掺量对硫铝酸盐-硅酸盐复合防腐砂浆(AIAM)的性能影响,探究了不同EVA掺量下,硫铝酸盐-硅酸盐复合防腐砂浆体系的微观形貌。结果表明,与不掺EVA的硫铝酸盐-硅酸盐复合防腐砂浆相比,掺杂1.37wt%EVA胶粉的复合防腐砂浆1d、28d抗压强度分别为24.9 MPa、53.5 MPa;1d、28 d抗折强度分别为5.8 MPa、7.5 MPa;7d拉伸粘结强度提高了87.5%,28d抗渗压力提高了50%。于此同时,随着EVA胶粉掺量的增加,1d复合防腐砂浆体系中钙矾石的形成速度加快,含量明显增加,结构的致密性提高。

In this paper,suphoaluminate silicate composite anticorrosive mortar doped with EVA rubber powder was prepared by physical blending PO 52.5 type silicate cement,42.5 type sulphate aluminate cement,fly ash(Ⅱ),sand of 0.30-0.60 mm size,ethylene/vinyl acetate copolymer rubber powder(EVA),hydroxypropyl methyl cellulose(HPMC),powder polycarboxylate water reducing agent(PCL)and ethers powder defoamer(XP).The influence of different EVA content on the properties of aluminate-silicate composite anticorrosive mortar was analyzed.The microstructures of aluminate-silicate composite anticorrosive mortar system with different EVA content were explored as well.Compared to inorganic anticorrosive mortar without EVA,the results indicated that compressive strength of inorganic anticorrosive mortar at 1 d and 28 d were 24.9 MPa and 53.5 MPa respectively after adding 1.37 wt%EVA rubber powder;The flexural strength at 1 d and 28 d were 5.8 MPa and 7.5 MPa respectively.The tensile bond strength at 7 d increased by 87.5%and the impervious pressure at 28 d increased by 50%.Meanwhile,with the increase of EVA rubber powder content,the formation rate of needle like ettringite of composite anti-corrosion mortar system at 1 d was accelerated and the compactness of the structure increases.