Influence Of Bottom Sediment On The Bearing Capacity Of Pile Based On Interaction Of Pile-soil

Many scholars pay attention to harmful effects of sediment which always exist at bottom of pile along with bored cast-in-place pile is generally used in any engineering field. They also study effects of bottom sediment by using different methods. Many researchful literature come up with some methods that are about cleaning hole and reinforcement of pile bottom.Bottom sediment has great effects on bored cast-in-place pile, particllarly on constructions which need higher bearing capacity and strictly restricted sedimentation. The studies of bottom sediment have necessity and provide guidance for engineering practice. Now, many finite element software have completed perfectly transformation from theory of finite element to application tool. This paper rely on finite element software which is workable and comprehensive on dealing with geotechnical problems and consider interaction of pile-soil to research an analysis influence of bottom sediment on the bearing capacity of bored cast-in-place pile. Researchful status of interaction of pile-soil and influence of bottom sediment, theory of finite element and choosing geometric model, constitutive model of soil, disposing contact surface of pile-soil, selecting displacement boundary condition and simulating initial crustal stress in ANSYS are introduced detailedly. In order to realizing deeply the influence of bottom sediment, this paper build some axisymmetric finite element models which are simulation commendably practical engineering, also analysis the effects from three sides including the thickness of sediment, the physical properties of sediment and length diameter ratio of pile. Thickness, elasticity modulus and internal friction angle of sediment and length diameter ratio of pile have obvious effects. Effect of thickness also has a critical value that is 300mm-400 mm. but cohesive force and poisson ratio of sediment are opposite. These conclusions can be used to guide or assist design and construction of bored cast-in-place pile, detection and disposing of bottom sediment et.