Reasons of the misalignment of experimental results on the concrete compressive strength

Through analzying the experimental processes about the concrete compressive strength,the reasons causing misalignment include discordance for the disjunction between measurement checking and practical usage and"non-perpendicular even" stress for the uncorrect operations,such as operating center is not on the same axis,unparrallelled operating levels from top to bottom,overlapping use of the ball,irregulated R cape.