Study on Influence of limestone powder on compressive properties and hydration heat of C60 concrete
In order to study the influence of limestone powder content on the mechanical properties and hydration heat of C60 high-strength concrete,the experiment was carried out to analyze the mechanical properties and hydration heat release of high-strength concrete with different specific surface areas and contents of limestone powder.The results show that the addition of limestone powder can effectively improve the compressive strength of concrete,and the increase range is between 1.3％and 19.3％.The improvement of concrete compressive strength is the most obvious under the limestone powder specific surface area is 6 000 cm2·g 1 and the content is 5％-15％.Since the activity of stone powder is much lower than that of cement,with the increase of limestone powder content,the total heat release of cementitious system gradually decreases and the time-hydration heat release rate curve shifts to the left,among which the hydration rate of S15-6000 group concrete is the fastest in the early stage.No newly generated phase is detected in the hydration product of cementitious system with the addition of limestone powder.When limestone powder content is 15％,the peak strength of Ca(OH)2 reaches the highest and meanwhile generates a large amount of C-S-H gel.The reason is that the addition of limestone powder has a dilution effect,and the increase of the water-binder ratio of cementitious system makes the cement obtain sufficient water during hydration.In addition,15％limestone powder content provides the best calcium content for the cementitious system to further promote hydration.The formation of a large amount of C-S-H gel provides a guarantee for the development of compressive strength of S15-6000 group concrete,and the group can make full use of limestone powder to a greater extent.
limestone powdercompressive strengthhydration heatspecific surface areace-mentitious system
万方数据
维普
