Based on the design principles of economic rationality and safety, multiple-pivot pile anchorage approach was used as the supporting engineering of a tall building with a deep foundation ditch. The designs, such as anchor arm, single pile and the whole, were set up in accordance with the calculations of the internal force from the equivalent beam and Yamagata Kunio methods. Moreover, the rationality of the design was estimated using the stability checks. FLAC3D was used for calculating the accuracy of the design. Using FLAC3D to simulating ditch cutting and supporting processes can obtain the equivalent results as the theory analysis in the displacement of ditch surrounding wall, the stress field and stress distribution.