摘要
冻融破坏是导致混凝土耐久性下降的重要因素。本文采用快冻法,结合某跨海大桥和青藏高原某水利工程,研究了聚脲涂层对提高海工和水工混凝土抗冻性的影响,并与环氧涂层进行对比研究。研究结果表明,无涂层高性能混凝土经275次冻融循环后,质量下降了5%以下,相对动弹性模量也下降到60%,产生冻融破坏;环氧涂层混凝土100次冻融循环后,涂层出现裂纹,250次时出现大面积脱落,425次后相对动弹性模量下降到60%。聚脲涂层混凝土600次冻融循环后,表面仍完好无损,质量及相对动弹性模量几乎不变。从聚脲涂层在某跨海大桥和青藏高原某水利大坝应用情况来看,聚脲涂层具有很好的抵抗海工和水工环境腐蚀的能力和抗冲击性能,即使在-45℃～25℃这样的大温差环境下,仍具有很好的适应性。
Concrete structure is destroyed seriously in many areas of our country,freezing-thawing is one of the important factors which lead to decreasing durability of concrete.The capacity of polyurea coating and epoxy coating resist frost was studied in this paper,and it showed that the quality of high performance concrete decreased by 5 percents when the cycle of freezing-thawing was 275,and the relative dynamic elastic modulus dropped to 60 percents;the surface of epoxy coated concrete was cracking when the cycle of freezing-thawing was 100,and large particles after 250 cycles,the relative dynamic elastic modulus decreased to 60 percents after 425 cycles;the surface of polyurea coating was still intact after 600 cycles,and the relative dynamic elastic modulus stayed almost unchanged.
出处
《大坝与安全》
2010年第5期1-5,共5页
Dam & Safety
关键词
聚脲涂层
环氧涂层
抗冻性
海工混凝土
水工混凝土
polyurea coating
epoxy coating
freezing resistance
marine concrete
hydraulic concrete
