Experimental study on vertical bearing capacity of pile foundation in east Gansu Province loess area

Abstract To explore the vertical bearing capacity of pile foundations in the loess area, relying on the new construction project, a single pile vertical compressive bearing capacity field test was conducted on three test piles, and the Q-S curve and S-lgt curve of the single pile vertical static load test The analysis and research showed that the axial force of the three test piles had not been transmitted to the pile end, and the load was mainly borne by the reaction force provided by the frictional resistance of the pile side. The distribution of the axial force of the pile with depth is not only related to the size of the pile top load, but the nature of the soil around the pile is related to the typical friction pile characteristics, and the Q-S curves all show a slow-change type with no obvious steep drop. When loading 4900kN, none of them reached the ultimate failure, and the settlements of the three trial-installed piles were 12.24, 15.44 and 18.64mm, respectively. By comparing the test results with the design requirements, the bearing capacity of the single pile meets the requirements, indicating that in the loess area, the single pile has a higher bearing capacity, and the settlement is more uniform and the settlement is small, which can be used as a building foundation to bear a larger load.