Abstract: The settlement behaviors of high loess-filled foundation usually plays a critical role in later construction planning. In order to investigate the settlement behaviors and affecting factors of high loess-filled foundation, a long-term in-situ monitoring was carried out to monitor the settlement of a high loess-filled foundation, pore water pressure and internal sedimentation of the filling body. Monitoring results show that instant settlement and consolidation settlement caused by the overlying soil loading are the main components of the settlement of the original saturated loess foundation. Moreover, the settlement and the pore water pressure tend to be stable at the same time, while no obvious creep deformation occurs during this process. On the other hand, the settlement of unsaturated filled foundation is largely dependent on the exhaust conditions. For example, the initial post-construction settlement of the soil with better exhaust condition is even more than 2 times of the soil settlement under non-ideal exhaust condition. Thus, variation of exhaust conditions is one of the main reasons for the soil settlement difference between the centrifugal model test and the in-situ monitoring. Properly slowing down construction speed and reasonably arranging exhaust passages are helpful to shorten the time of post-construction settlement stabilization and save time for subsequent construction.

Key words: high loess-filled foundation, original foundation, filled foundation, settlement behavior, exhaust condition