天然与再生集料透水混凝土对比试验

Comparative Study of Porous Concretes Using Natural and Recycled Aggregates

为了开发具有可接受的透水性和强度的透水混凝土,使用天然和再生集料,采用最佳的混合比例制备透水混凝土,对透水混凝土进行孔隙率、渗透系数、抗压及抗弯强度试验,研究了再生集料对总孔隙率、强度和渗透性的影响.同时,在混合料中引入了丁苯橡胶类可再分散性聚合物粉末(RPP)和胶乳(Latex)以提高其强度特性.试验结果表明:掺加再生集料的透水混凝土总孔隙率比采用天然集料的透水混凝土孔隙率要高;无论何种集料类别,聚合物改性剂的添加使得总孔隙率略有降低;使用再生集料透水混凝土的抗压强度低于使用天然集料的透水混凝土;然而,当使用聚合物改性剂时,采用天然和再生集料透水混凝土的抗压强度分别提高57%和79%;再生集料及最佳聚合物掺量的使用可以生产出具有足够排水和强度特性的透水混凝土.

The purpose of this study was to develop porous concrete with acceptable permeability and strength using recycled aggregate. The optimum mix proportions were employed to prepare porous concretes using natural and recycled aggregates. Tests carried out on porous concrete were void ratio, coefficient of permeability, compressive and flexural strengths. The effects of recycled aggregate on total void ratio, strength and permeability were examined. Styrene butadiene rubber - based redispersible polymer powder and latex were introduced to mixtures to improve strength properties. The total void ratio of porous concrete incorporating recycled aggregate was larger than that of porous concrete with natural aggregate. The addition of polymer modification resulted in a slight decrease in total void ratio regardless of type of aggregate. The compressive strength of porous concrete using recycled aggregate was lower than the one using natural aggregate. However, the compressive strengths of porous concretes using natural and recycled aggregates were significantly improved by 57% and 79% respectively, due to polymer modification. The use of recycled aggregate along with optimum content of polymer could produce porous concrete with both enough drainage and strength properties.