改性聚丙烯纤维混凝土用于堆石坝面板的几个问题

Problems in Applying Modified Polyacrylic Fibrous to Face-plate of Rockfill Dam

聚丙烯纤维的加入能防止和减少混凝土开裂,提高混凝土的变形性能并使防渗、抗冻融性和韧度指标显著提高,因而适用于堆石坝的面板混凝土。由于聚丙烯纤维的应用,有可能采用更合理的面板结构和尺寸,提高其耐久性和经济性。为此,对聚丙烯纤维的品质应有一定要求,主要是和水泥砂浆的握裹力及抗老化性能。不同地区和不同部位的面板混凝土中,聚丙烯纤维的合理掺量应有所不同。讨论了进一步发展聚丙烯纤维混凝土在堆石坝面板和其它水利工程中应用的几个问题。

Adding polyacrylic fibre to concrete of face-plate for rockfill dam will prevent from or reduce cracking of concrete, raise deformability of concrete and improve its impermeability,toughness and resistance to freezing and thawing. Application of polyacrylic fibre will lead to more rational structure and size of face-plate and highten its durability and economy.Hence,quality of polyacrylic fibre,mainly,the grip between fibre and cement mortar and ageing resistance should meet cretain requirements.Rational quantity of polyacrylic fibre added should be different according to region and location of facing concrete.The paper also discusses problems in further developing the application of polyacrylic fibrous to concrete-faced rockfill dam and other hydraulic project.