热养早期推定混凝土抗氯化物渗透能力研究

Prediction of concrete resistance to chloride penetration by heating up curing at early ages

通过分别测试热养和标养混凝土抗氯化物渗透性能指标,采用统计分析的方法分析热养和标养混凝土性能指标的关系。研究表明标养与热养混凝土抗氯化物渗透性能指标之间相关性较强,进而在大量试验的基础上建立热养早期推定混凝土抗氯化物渗透性能指标的经验公式,制定热养早期推定混凝土抗氯化物渗透性能指标的试验方法。该方法使海工混凝土电通量(ASTMC1202)的确定时间由28 d缩短为4 d,氯离子扩散系数(NTBUILD443)的确定时间由原来的130 d缩短为43 d,大大缩短了混凝土抗氯化物渗透性能的常规检测周期,对海工混凝土耐久性指标的施工质量控制和配合比设计具有重要意义。

In this study, the indexes of concrete resistance to chloride penetration are tested by heating up curing and standard curing separately and the relationship between the indexes is analyzed.The results indicate that there is close relation between the indexes.Then the empirical formula for predicting the concrete resistance to chloride penetration at early ages by heating up curing is established and the experimental procedures are determined.Through this method,the time of determining the quantity of electric charge of marine concrete （ASTM C 1202 ） is shortened from 28 days to 4 days, and the time of determining the concrete chloride diffusion coefficient （NT BUILD 443 ） is shortened from 130 days to 43 days. Thus, the conventional testing cycle of concrete resistance to chloride penetration is greatly shortened, which is of great importance to construction quality control and mix proportion design of marine concrete durability index.