Effect of water-entraining admixtures on the hydro-mechanical properties of ultra-high performance c

来源 :The 14th International Congress on the Chemistry of Cement ( | 被引量 : 0次 | 上传用户:nyxjm2008
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  The objective of this research is to understand the hydration and engineering performance of superabsorbent polymers as an internal curing agent in ultra-high performance concrete.Two different types of superabsorbent polymers of acrylic acid and acrylic amide with similar particle size profiles were systematically tested.To estimate the water absorbent capacity of the polymers, tea-bag tests using distilled water were performed.Isothermal calorimetry and x-ray diffraction experiments revealed the impact of polymers with different chemical bonds on cement hydration, in terms of hydration degree and hydration products.To test its feasibility as a shrinkage reducing admixture for ultra-high performance concrete, compressive strength,flowability, and autogenous shrinkage profile were measured.Lastly, scanning electron microscopy and computed tomography showed a multi-scale porosity network of the concrete with superabsorbent polymers.While both polymers showed a reduction in autogenous shrinkage, it has been concluded that the particle size and chemical form of each polymer affected its role as an internal curing agent in concrete.This also significantly affects cement hydration and mechanical strength.While acrylic acid polymer has more absorption capacity of distilled water, acrylic amide polymer shows better performance in low water-to-cement concrete systems.
其他文献
The objective of this study was to investigate the early-age (24h) cracking behavior of self-compacting fiber reinforced cementitious composites (SC-FRCC) with five different fiber volume fractions (V
Developing multifunctional cement-based materials has been a long engineering pursuit that holds great promise and impact for altering the building materials landscape.However, despite recent progress
As for modem high performance precast concrete, the use of early strength water-reducers is the main method to improve the early strength, shorten the steam curing time, speed up the turnover rate, re
The stability of fresh cement paste can be described as its ability to remain homogeneous over time.Instability in the form of sedimentation and bleeding occurs for various reasons related to the mate
1H-Time-Domain-NMR is a non-destructive bulk method providing detailed information about the different physical environments of hydrogen during chemical reactions.Low financial impact in maintenance a
In order to investigate the feasibility and superior of volcanic rocks used as pozzolan in cement-based composite,the volcanic rocks from the east region of Jiangxi Province, China, were collected for
Reactivity and cementitious properties of copper tailings irradiated by microwave at different power has been investigated.The dissolution quantities of Si4+, Al3+ of irradiated copper tailings were t
Flocculation of cement particles depends on shear rate.The change of particle size was often monitored via a laser reflectance measurement, where the increase of cement particles was observed.The rota
In this paper, the cement production pulverized coal combustion characteristics experiment was done respectively at 21%, 30%, 35%, 40% and 100% oxygen concentration, on this basis, the pulverized coal
Sprayed concrete differs from ordinary concrete due to the method of application and the use of set accelerators to promote immediate stiffening of the matrix right after mixing.Hydration kinetics, re