摘要
由于天然河砂的不可再生性和环境保护的要求以及西南片区长江水域多为特细砂,达不到II区中砂要求。外购河砂价格昂贵不经济。机制砂代替河砂将是今后水泥混凝土技术的研究方向。机制砂因其自身特点,拌制的混凝土流动性差,其工作性能不如河砂,尤其是高墩大跨结构泵送施工难度较大。通过对机制砂生产工艺严格要求,正交设计优化配合比,调整减水剂的引气保坍缓凝组分,进行水泥与减水剂匹配性试验,加强对环境温度敏感的预防措施和施工过程降低混凝土与管道的摩阻力,提高了混凝土的可泵性能。该标段高墩大跨结构的泵送机制砂混凝土施工取得圆满效果,拌合物堵管问题得到了有效控制,也收到了良好的技术经济效果。
Since the weak of natural river sand is obvious that it is non-renewable resource and required in environmental protection,and belongs to extra fine sand in most Yangtze river area of Southwest China falling short of the requirements of medium sand of Area II,and is expensive in outsourcing,it will be the research direction of cement concrete technique that machine-made sand replaces the river sand in future.For the self features of machine-made sand that it is in week liquidity,poorer working performance than river sand,especially that it is difficult in pumping construction for high pier and large span structure,through strictly demanding the machine-made sand in manufacturing technique,design optimization of orthogonal design,and adjusting the retarded components of water reducer with gas introduction and collapse protection,performing matching test for cement and water reducer,taking preventive measures for sensitive environment temperature and decreasing the frictional resistance between concrete and pipe,the pump-ability of concrete is well improved.The construction of machine-made sand concrete for high pier and large span structure achieved successful results and the block of tube is effectively controlled as while sound economic results were attained at the same time.
作者
刘郁
郭秋生
Liu Yu;Guo QiuSheng(The 4th Engineering Co.,Ltd.of China Railway 12th Bureau Group,Xi'an,Shanxi 710021;Beijing Vocational College of Finance and Trade,Beijing 101100)
出处
《江西建材》
2019年第3期44-47,49,共5页
Jiangxi Building Materials
关键词
高墩泵送
机制砂混凝土
工作性能
正交设计
配合比
质量控制
Pumping for high pier
concrete in machine-made sand
Working performance
Orthogonal design
Mixture ratio
Quality control
