Wall Effect Of Aggregate In View Of Image Analysis And The Study Of The Hydration Degree Under The Wall Effect

The wall effect of concrete structure can weak the properties of concrete surface.It has an important influence on the durability of concrete. Scholars at home andabroad have a large number of studies on the wall effect of concrete. Image analysis isan important method. This article is mainly based on MATLAB functions for imageanalysis to identify artificial aggregate. It can extract the aggregate properties withinthe specified area of the analysis region, such as the area, the centroid, the equivalentdiameter and the angle between the long axis and the x-axis. Through the analysis ofaggregates properties of section by1mm, we can get the change of aggregatedistribution along the depth. This paper studies the effects of different water-cementratio, maximum aggregate size and different templates location on the aggregatedistribution at constant quality in One-dimensional direction. It also studies thecoupling effect of two perpendicular boundary on aggregate distribution. By measuringthe content of Ca(OH)2at different depths, we study the degree of hydration on theWall effect of concrete under a certain age of concrete.Studies have shown that in the one-dimensional direction, aggregate area fraction curve along the depth direction for the first rise and then fall, in the last it will finally stabilized. Aggregate distribution curves at different positions of the template duo tothe effect of gravity on the spatial distribution of the aggregate will producedifferences. Vertical distance from the bottom of the template increases with increasingdepth of the peak point. It is not a simple linear relationship. It is almost no effect onthe sides and bottom of the aggregate distribution curve. The study of the relevantparameters of the special section of the aggregate distribution explains the impact ofaggregate equivalent particle and its corresponding number, area fraction and gradedchanges in the change of aggregate fractional area. The coupling effects of aggregatedistribution duo to the two perpendicular boundary makes the same aggregate volumefraction curve as an arc. Hydration degree curve in the wall effect under a certain agefor the first horizontal section and then dropped the final stabilized，Increment inwater-cement ratio makes hydration degree curve increase but will not affect the overall trend.