模板衬里改善表层混凝土质量的机理研究

Research on Mechanism of Surface Concrete Properties Improved by Controlled Permeable Formwork Liner(CPFL)

测试了不同侧压下蓄水型模板衬里的持水能力、水泥净浆及砂浆的养护用水量以及不同龄期混凝土的表面硬度,探讨了模板衬里改善表层混凝土质量的作用机理.结果表明:采用蓄水型模板衬里可实现混凝土的持续保湿养护;模板衬里对早龄期混凝土表面硬度的提高明显高于较长龄期混凝土表面硬度.模板衬里促使排水排气过程中胶凝材料细微颗粒向混凝土表层富集,使得表层混凝土中胶凝材料的早期水化程度高,同时又不间断地保湿养护表层混凝土,从而改善了表层混凝土的质量.

Water-retaining ability of impounding type controlled permeable formwork liner（CPFL） under different lateral pressure,water requirement of cement paste and mortar in curing process,and concrete surface hardness at different age were measured,and the mechanism of surface concrete properties improved by CPFL was researched.Test results show that lasting moisture curing of concrete can be realized with impounding type CPFL.The improvement degree of concrete surface hardness at early age is more remarkable than at longer age by using CPFL.In the process of drainage of water and air out of concrete surface,CPFL could impel the finer particles of cementitious materials migrate towards concrete surface,make the cementitious materials hydrate fast,and keep moisture of surface concrete for some days,so it can improve the properties of surface concrete.