摘要
采用机制砂分别按照0%、25%、50%、75%和100%等量替代天然河砂制备C25~C55不同强度等级的泵送混凝土,研究机制砂对混凝土工作性和抗压强度的影响。结果显示,对于C25~C40强度等级混凝土,机制砂替代天然砂比例低于50%时对工作性影响不大;对于粉料量较高的C40以上混凝土,机制砂替代比例可提高到75%仍不影响工作性;但完全采用机制砂替代天然砂则容易造成离析;机制砂替代天然砂比例低于50%时对各强度等级混凝土的强度均无影响,对于高强混凝土则能够在低于75%的代砂率条件下强度都略提高,但完全采用机制砂替代天然砂则对各强度等级的混凝土抗压强度都不利。
C25to C55 pumped concrete of different strength grade are preprepared by mechanism sand which equivalent substitute natural river sand by 0%,25%,50%,75%and 100%respectively.The mechanism of sand on the workability and compressive strength of concrete is investigated.The results show that for C25～C40concrete strength grade,the workability is hardly impacted when mechanism sand in steading of natural sand ratio is lower than 50%.For above C40 concrete with higher powder,mechanism of sand does not affect the workability,even through the replacement ratio is up to 75%.But if sand mechanism completely replace natural sand,it is easy to cause segregation.For every strength grade of concrete strength,the compression strength will be not influenced at all when the proportion of mechanism sand instead of natural sand is less than 50%.For the high strength concrete,the strength can be improved a little until the replacement of mechanism sand instead of natural sand is up to 75%.But the compressive strength of different strength grade of concrete will be adverse if the natural sand is replaced by mechanism completely.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2014年第7期30-34,共5页
Journal of Wuhan University of Technology
关键词
机制砂
混凝土
坍落度
抗压强度
manufactured sand
concrete
slump
compression strength
