免压蒸PHC管桩混凝土的制备研究  

Preparation Study of Non-autoclaved PHC Pile Concrete

作　　者：夏艳晴 石战战[1] 

机构地区：[1]成都理工大学工程技术学院,614000

出　　处：《混凝土与水泥制品》2018年第7期32-35,共4页China Concrete and Cement Products

摘　　要：利用特种硅酸盐水泥FACC制备了免压蒸PHC管桩混凝土,研究了水泥掺量、水灰比、砂率、静停时间、升温速率、恒温时间、温度等因素对PHC管桩混凝土蒸养强度的影响,并采用XRD和SEM等表征方法对水化产物进行了矿物成分和形貌分析。结果表明,免压蒸PHC管桩最佳混凝土配合比为FACC 480 kg/m3、水灰比0.26~0.28、砂率32%~37%、养护制度为20℃静停2 h、升温速率0.3℃/min、恒温温度90℃、恒温时间4~6 h,开盖自然冷却脱模。在此基础上制备的免压蒸PHC管桩混凝土能减少延迟钙矾石的形成,强度达到C80以上,满足PHC管桩的使用要求。The non-autoclaved PHC pile concrete with special portland cement FACC is prepared. The parameters affecting the compressive strength of PHC pile concrete, such as cement content, W/C , sand ratio, rest period, heating rate, constant temperature and time etc. are investigated. Moreover, the type of hydration products is investigated by using S E M and XRD . The results show that the compressive strength of PHC pile concrete whose mix proportion is FACC 480 kg/ m^3, W/C ratio 0.26-0.28, sand ratio 32%-37% can meet the requirements in some areas. Furthermore, the experiment shows the best steam-cured system is 20℃ rest period lasting 2 h, heating rate at 0.3℃/ mi n, constant temperature at 90℃, constant temperature time lasting 4-6 h, nature cooling. The excellent mix ratio and steam-cured system can avoid the risk of expansion damage from delayed ettringite formation.

关 键 词：强度 配合比 蒸养制度 延迟钙矾石反应 特种硅酸盐水泥 

分 类 号：TU525.9[建筑科学—建筑技术科学]