Analysis And Design Optimization Of Construction Board Extension Foundation On Layered Foundation

With the development of economy,people have a higher pursuit of living environment.There are multi-storey,small high-rise building forms,which not only ensure the stability of the building,but also meet the site use requirements of underground garage,equipment room,underground shopping mall and other supporting facilities.Therefore,a new type of foundation,the expanded foundation,has emerged.The expanded foundation has good bending resistance,can fully enlarge the size of the foundation bottom,and achieve the purpose of reducing the foundation stress.Compared with the box foundation and raft foundation,the expanded foundation has the characteristics of clear force transfer form,low engineering cost,simple structure and easy construction Point.However,there is no clear stipulation in the code,so the research on the bearing capacity of the structural plate spread foundation becomes particularly important.This paper takes the Liaoning Provincial Culture and Art Center and the new provincial museum project as the background,and studies the bearing capacity through numerical simulation and formula derivation.The specific research contents are as follows:ABAQUS finite element software is used to establish the integral and separate model of the structural slab spread foundation.The correctness of the model is verified by comparing with the measured data,and the variation laws of the corresponding base compressive stress,bending moment,shear force and displacement are obtained.On this basis,the groundwater level is introduced to explore whether the variation laws of the groundwater level on the foundation and the foundation are consistent with the formula derivation,Finally,the parameters of the foundation are optimized and the bearing capacity is checked.Numerical analysis is carried out for the structure slab spread foundation.The results show that:with the increase of the upper load,the compressive stress and displacement of the base increase,the compressive stress of the slab on the column is greater than that of the mid span slab,the compressive stress of the slab support is greater than that of the mid span slab,and the tensile stress at the contact between the structural slab and the spread foundation is greater than the maximum allowable tensile stress of 1.54 MPa,The structural plate spread foundation is compressed as a whole,resulting in the deformation of inward depression.The groundwater level is used to analyze the variation of foundation.The results show that:when the groundwater level is above the base,the groundwater level decreases,the compressive stress and displacement of the base increase;when the groundwater level is below the base,the groundwater level decreases,the compressive stress and additional stress of the base remain unchanged,the self weight stress and settlement increase.The foundation parameters are analyzed numerically.The results show that:select 0.7m thickness of structural plate,5.4m × 5.4m × 0.6m spread foundation reduces the curve fluctuation and numerical value of foundation settlement and base stress,and the checking calculation of bearing capacity meets the requirements.