Concrete expansion character testing device

The utility model discloses a concrete expansion character testing device comprising an annular mold, a base and an annular indicator, wherein the annular mold is an annular cylinder with a notch, the length of the notch is equal to the height of the annular mold and the length direction of the notch is parallel to the axial direction of the annular mold; the base is provided with a supporting hole adaptive to the outer diameter of the annular mold and provided with a closed lower end; the annular indicator comprises an annular end and indicators, the annular end is provided with a second notch which has a same width to the notch of the annular mold, each end part of the second notch is connected with one indicator, and the extending direction of two indicators are parallel to each other; and the inner diameter of the annular end is adaptive to the outer diameter of the annular mold, therefore the annular end can be sleeved at the periphery of the annular mold. During test, the annular mold, the base and the