Analysis Of Bearing Capacity For Box And Bucket Foundation On Soft Soil

When structures are built on soft soil, bearing capacity can be hardly satisfied as the soil has the characteristics of high water ratio, high compressibility and poor shear strength. However, bearing capacity can be improved through structure-self by taking full advantage of the interaction between structure and soil. The paper mainly studies the bearing capacity of box and bucket foundation on soft soil with Hardening-Soil Model.Firstly, comparing the measured value of the experiment with the one of the Plaxis simulation, the results show good effect that Hardening-Soil Model is able to simulate the bearing capacity of box and bucket foundation on soft soil.Sencodly, the paper studies ultimate bearing capacity of the structure on one layer soil. In addition to the general nature of the soft soil,it also has some specific characteristics, for instance, the friction angle is almost zero and the cohesive strength is linear growth as the depth increase.The influence factors of structure form, structure dimension and parameter of soil are analyzed on 3-D FEM, and modified formulas of quadrate, circular and strip box and bucket foundation are concluded. Furthermore,the failure of the foundation is analysed.Thirdly, stratified soil is also studied on the basis of research on one layer soil. The influence on bearing capacity of structure dimension, parameter of soil and the thickness of the layer are analyzed. Additionally, it is concluded that the softened soil around the sidewall due to wave action has small influence on the total bearing capacity and structure stability in design situation.Finally, using FEM program Plaxis, the paper establishes numerical analysis model of box and bucket foundation with Tianjin harbor breakwater extension project and the construction of lying box structer with Zhangdong sea road and field project. The results show that both the bearing capacity of two projects are well satisfied. The coefficient of resisting force is also obtained. Besides, directed toward the bearing capacity of new wharf type with bucket foundation,the paper do some research.In conclusion, This paper mainly carries on the analysis of bearing capacity of box and bucket foundation on soft soil. The research findings have great significance on the application of the structure on offshore construction, and it can also provide some references for the design and bearing capacity caculation of the structure.