大坝现场浇筑期混凝土性能分析

Performance Analysis of Concrete during Site Pouring of Dam

为了准确评价现场浇筑养护混凝土强度性能,依托某大坝工程,在春夏秋冬4个季节内分别浇筑成型低热水泥全级配混凝土和湿筛二级配混凝土,研究不同浇筑季节和不同养护龄期对混凝土强度性能的影响,通过对比全级配混凝土和湿筛混凝土的抗压强度、劈裂抗拉强度、轴心抗压强度以及静力抗压弹性模量,为同类工程采用低热水泥混凝土的强度性能提供参考。结果表明,浇筑季节对混凝土的强度性能存在影响,养护龄期180d时整体强度差异较小;在相同浇筑季节下,湿筛二级配混凝土的各项力学指标均高于全级配混凝土;抗压强度和劈拉强度换算比均值分别为0.82和0.71,可采用换算比平均值来评价低热水泥混凝土的强度性能。

In order to more accurately evaluate the strength performance of on-site pouring and curing concrete,this paper,based on a dam project,casts and forms low-heat cement full grade concrete and wet screen secondary concrete respectively in spring,summer,autumn and winter to study the influence of different pouring seasons and curing ages on the strength performance of concrete.By comparing the compressive strength,split tensile strength,axial compressive strength and static compressive elastic modulus of fully graded concrete and wet screened concrete,the paper provides a reference for the strength performance of low hot water set concrete used in similar engineering.The results show that the pouring season has an effect on the strength performance of concrete,and the overall strength difference is small at the curing age of 180d.Under the same pouring season,the mechanical indexes of wet sieved secondary concrete are higher than those of full grade concrete.The average conversion ratio of compressive strength and split strength is 0.82 and 0.71,respectively.The average conversion ratio can be used to evaluate the strength performance of low-heat cement concrete.