Foundation engineering method and construction apparatus for producing a columnar structure in the ground

A foundation engineering method for producing a columnar structure in the ground, in which a foundation engineering tool is driven in a rotating manner about an axis of rotation and introduced with a feeding motion into a ground, wherein the columnar structure is produced in the ground, wherein during the production of the columnar structure a rotating motion and a feeding motion of the foundation engineering tool are recorded over time and forwarded to an evaluation unit, by means of a sensor means at least one further processing parameter is recorded over the time during the production of the columnar structure in the ground and is forwarded to the evaluation unit and in that by the evaluation unit a three-dimensional model of the columnar structure is produced and displayed, wherein by the evaluation unit a helical time axis is formed depending on the rotating motion and feeding motion recorded over time and in that the at least one processing parameter recorded over time is assigned to the helical time axis in order to form the three-dimensional model.