三河口大坝碾压混凝土配合比试验研究

Study on mix proportion of roller compacted concrete in Sanhekou Dam

目前,针对在秦岭腹地南北气候分界线地带特殊区域内建设的碾压混凝土大坝的混凝土配合比如何确定,经验尚少。通过三河口水利枢纽大坝碾压混凝土配合比试验研究,总结了该特殊区域的碾压混凝土配合比设计的经验,可为引汉济渭工程黄金峡碾压混凝土大坝的建设提供依据,也为碾压混凝土筑坝技术在秦岭腹地的推广应用打下良好基础。该试验成果已成功应用于三河口水利枢纽大坝工程中,其水泥、粉煤灰、砂石骨料、外加剂等均满足规范要求,各种强度等级碾压混凝土配合比的胶凝材料总量合适、力学性能满足设计要求、抗渗与抗冻等级较高、耐久性良好。

At present,the experiences of how to determine the concrete mixing ratio for the roller compacted concrete dam constructed within the particular region in the south-north climatic boundary zone of the central region of Qinling Mountains are less.Through the experimental study on the roller compacted concrete mixing ratio for the construction of the dam for Sanhekou Water Control Project,the experiences from the mixing ratio design of the roller compacted concrete for the particular region is summarized herein,which cannot only provide a basis for the construction of Huangjinxia RCC Dam of Hanjiang-to-Weihe River Valley Water Diversion Project,but also can lay a better foundation for popularization and application of the roller compacted concrete dam construction technology within the central region of Qinling Mountains. The achievement got from the experiment is already successfully applied to the construction of the dam for Sanhekou Water Control Project,in which all cement,fly ash,sand-gravel aggregate,admixtures,etc. can meet the requirements from the specifications concerned,while the total amounts of the cementitious materials for the mixing ratios of the roller compacted concretes with all the strength classes are adaptable,for which the mechanical performances meet the design requirement,the anti-seepage and anti-freeze degrees are higher and the durabilities are better as well.