Calculation of Ultimate Bearing Capacity of Double-Layer Structure Foundation Building Backfilled with Fly Ash
In order to improve the accuracy of calculating the ultimate bearing capacity of fly ash backfilled foundation,this paper proposes a method for calculating the ultimate bearing capacity of double-layer structure foundation buildings with fly ash backfill.Construct a double-layer foundation structure consisting of an upper hard shell layer and a lower weak layer using dynamic compaction method,and analyze its stress situation;Calculate the bearing capacity coefficient of the foundation at different burial depths,and determine the overall shear failure bearing capacity of the weak lower layer,the impact shear failure bearing capacity of the hard shell layer of the upper foundation,and the settlement friction force between the foundation soil and the foundation sidewall based on the bearing capacity coefficient.The results show that when the ratio of foundation depth to width is greater than or equal to 4,the variation of the ultimate bearing capacity curve of the foundation tends to be stable;The local foundation has a burial depth of 1.2 meters.When the principal stress coefficient is 0.5,the bearing capacity of the foundation is 5.0 MPa,and when the principal stress coefficient is 1,the bearing capacity of the foundation is 5.5 MPa;Under the same principal stress coefficient,it will increase with the increase of the burial depth of the foundation.The above results indicate that the evaluation results can provide data support for the stability performance of upper level buildings.