Foundation pit supporting performance evaluation method and device considering water level fluctuation and supporting aging

The invention discloses a foundation pit supporting performance evaluation method and device considering water level fluctuation and supporting aging, and the method comprises the steps: determining the rheological characteristics of a soil body in an engineering site, the change of underground water and the loss rule of the prestress of an anchor cable according to the triaxial test and construction process of a rock-soil body; determining expressions of soil pressure, underground water level and anchor cable prestress changing along with time according to rheological characteristics of a soil body of an engineering site, underground water change and anchor cable prestress loss; determining a deformation coordination relationship between a pile body and an anchor rod in combination with basic assumption of a foundation pit pile-anchor support model; meanwhile, the rheological property of a soil body, anchor cable prestress loss and underground water change are considered, and the basic theory of an elastic f