The Theoretical Analyses And Applications Of Settlement For Bridge Friction Pile Foundations

The stability of bridge embodied on the strict control of deposition process, when the bridge is built on the soft ground. Generally, as long as the settlement stability meets the requirements, the strength requirements will be satisfied too. The deformation stability of foundation and settlement prediction after working is the key to the design and construction of bridge. If the settlement can not satisfy the requirement of designing, reinforcement of foundation measures will be taken to satisfy the settlement requirements.In recent years, due to the lack of foundation settlement control, there is quite a lot of houses tilt and bridges collapse accidents. The foundation settlement problem attracts much attention, and the academic also pay much attention to the problem. So how to control the foundation settlement better becomes a major problem to be solved.The main contents of this paper and the research results are included as follows:①Based on the load transfer method and Biot consolidation theory ,and considering the linear viscoelastic properties and consolidation of soil over time as well as other variables ,the three-dimensional relationship between settlement and time under static loads are theoretically derived,analyzed and researched.②In order to test and verify the desirability and rationality of the three-dimensional pile settlement formula, and to get the changing discipline of bridge foundation settlement over time, this article calculated and researched the pile foundation of Jiangyin Yangtze River Bridge using the FLAC3D geotechnical calculation software and the one-dimensional and three-dimensional theoretical solution. Comparing the results, we can get the conclusion: the two analytical solutions can not simulate the flat section of loading, but under the same load, the three-dimensional analytical settlement solution is much safer, and bigger than both the finite element results and the one-dimensional analytical results. Comparing with the one-dimensional analytical results, the settlement is larger up to 13mm.③Through the analysis, we can get the conclusion :if other parameters are certain , with the increase of pile length , pile settlement reduced ;and with the increase of pile length ,the pile settlement reduce speed reduced too. When the p ile diameter is less than 0.5m, the pile settlement is larger, and with the increase of pile diameter, pile settlement reduce amount increased. When the modulus value is very small, the pile settlement will be very large; but when the modulus is larger than one certain value, the settlement will have little changes.