Abstract: The prestressed anchor cable anchoring technology is widely used because it can effectively control the slope deformation, but at the same time, there are also a lot of engineering failure problems caused by the loss of anchoring force. Based on M-2K model, this model is established, which is suitable for M-B-B model for creep coupling of anchor cable and slope in Loess. Meanwhile, the corresponding constitutive equation, relaxation equation and creep equation are derived, which theoretically solves the relationship between the change of anchorage force and slope creep. Taking an unstable slope treatment project in Chengguan District of Lanzhou City as an example, the genetic algorithm is adopted, which can reversely calculate the creep parameters of the model soil. The results are compared with the existing M-K-B model. The results show that the M-B-B model is more suitable for high slope in loess area, and it can be used to predict the change of prestress in the long run. The project is divided into filling soil, which leads to large horizontal deformation of filling soil. There is a slow rise stage of prestress before the stable stage of prestress loss, and the M-B-B model can perfectly fit this change. The research results can be used as reference for the design, construction and safe operation of anchorage engineering.

Key words: loess area, creep coupling, prestress loss, horizontal deformation, anchor technology