Study on the Influence of Pile Caps and Foundation Bottom to Foundation Beams
|School||Huazhong University of Science and Technology|
|Keywords||basement structure foundation beams zone of pile caps stability againstfloating bending moment of the center beams|
With the development of economic and the expansion of urban scale, thedevelopment of underground facilities are playing increasingly important role in savingland resources, improving the urban land use structure and so on. As a kind of deepfoundation, pile is widely used in bearing underground facilities and anti-floating.Generally, bearing platform, which is necessarily needed between pile and column in civilengineering, form a node domain of large stiffness in the ends of foundation beam withpile. The foundation plate of deep foundation pit often requires a large thickness becauseof its anti-floating effect. The node domain and thick plate can significantly affect theforce and deformation of the foundation beams. Therefore, the discussions of the affectionof the pile caps and thick plate toward foundation beams and the allocation proportion ofthe beam have important practical significance on the reasonable design of foundationbeams.Based on the review of the current research of foundation beams and the describe ofsimplified calculation and finite-element methods of the foundation beams, this papersimplified the calculation analysis of the foundation beams using mechanical method, andthen carried through finite-element analyze of the foundation beams under the force of thebuoyancy of water with the use of SAP2000. The main research contents are as follows:1.simplified to respectively engineering piles reaming bearings and spring, researchbetween pile caps foundation beams of the uniformly distributed load, triangular loadstress, and the formula of bending moment foundation beams cross a simplified formula;2.simplified to spring engineering piles, the pile caps in the pile foundation beamsbetween bending moment and axial force under the action of poor stress distributionproportion;3.make use of the power foundation in standards of stiffness of pile, the calculationformulas of calculation normally the stiffness of pile respectively, the triangle load andcolumn in the forces of the internal force redistribution of the foundation beams of thesimplified calculation formula deduction, discusses the law;4.under the condition of thick plate, pile caps foundation beams of the groundwater in between on under the action of buoyancy by finite element analysis, and will analyze theresults, and a simplified formula calculation result of the comparison and analysis, thispaper discusses pile caps and base plate foundation beams of the stress influence of thedegree.Results of the study show that: in the stability against floating, elevated pile caps andthe existence of a floor lower bending moment of the center beams; In the column ofexternal force, the appropriate consideration should be based on the distribution of theexternal force beam role.