Improved Algorithm And Application Of One-dimensional Consolidation Theory For Soft Soil Foundation

Biot consolidation theory is strictly based on the formula that the volume deformation of the elastoplastic body is equal to the permeability flow rate,which has the advantage of high precision of rigorous theoretical calculation,but it must be calculated with the help of finite element software,which makes it difficult for engineers and technicians to use.Although many assumptions have been made in the taisha one-dimensional consolidation theory,it has a simple calculation method and is more easily accepted by engineers and technicians.However,the traditional tai-sha-base one-dimensional consolidation theory assumes that the pore ratio and permeability coefficient in the consolidation process are constant,and the calculated results are often different from the measured values in engineering applications.The purpose of this paper is to study the improved algorithm of taisha one-dimensional consolidation theory and to develop computing software for engineers.Different initial consolidation condition is presented in this paper,in the process of consolidation of soil pore ratio and permeability coefficient calculation formula,and its formula is introduced into the soil consolidation,too sand for traditional one-dimensional consolidation equation of consolidation coefficient is revised,and on the basis of the formula of the adjusted coefficient of consolidation,further improved the traditional too until a one-dimensional consolidation equation.The calculation software of the improved algorithm for taishaki one-dimensional consolidation equation is developed,and the reliability of the improved algorithm is verified by comparing the calculation results of the software with those of the traditional theory.The ABAQUS finite element software was used to establish the numerical calculation model,and the calculation results were compared with those of the software in thispaper,which further verified the rationality of the improved algorithm for the taisaki one-dimensional consolidation equation created in this paper.Finally,the improved consolidation equation algorithm and calculation software are applied to the actual calculation of kaiyang expressway reconstruction and expansion project.The main work and achievements are as follows:(1)According to the different initial consolidation state of soil,the analytical calculation formula of pore ratio changing with soil consolidation process is derived,and it is introduced into the empirical formula of the permeability coefficient of reach west and the empirical formula of the corsen-carmen permeability coefficient,and the permeability coefficient prediction formula that can consider the influence of different consolidation state and consolidation stress is obtained.Will establish above to considering the effects of consolidation and consolidation stress formula of void ratio,coefficient of permeability in consolidation coefficient formula,and further to improve the traditional too until a one-dimensional consolidation equation,finally got to different consolidation state of soil,and at the same time considering the void ratio and coefficient of permeability changing with the consolidation process is too until the one-dimensional consolidation equation of the improved algorithm.(2)With the help of Visual Studio software,a simple interface program is prepared.The traditional taisha one-dimensional consolidation equation and the improved one-dimensional consolidation equation are programmed into the program at the same time,which is convenient for engineers and technicians to use.A simple example is used to compare the results of the consolidation stress and different consolidation states.It is found that the consolidation calculation results of the improved theory always lag behind those of the traditional theory due to the consideration of the compaction and the compression of the pore ratio during the consolidation process,and the difference between the two increases obviously with the increase of the overlying load and the increase of the compressed pores during the consolidation process.(3)Using ABAQUS finite element software,using the same parameters as the self-programming example calculation,and calculation results will be compared with calculation results of self-programming examples,analyzes the Biot consolidation theory and traditional too him one-dimensional consolidation theory,and in this paper,the improved too until the calculation results of one-dimensional consolidation theory,the calculation results of the two factors was very consistent,in order to further verify the reliability of the improved theory.(4)Respectively before and after using improved too him one-dimensional consolidation theory,USES the mizar highway reconstruction project of the measured physical parameters is calculated,the calculated results with the monitoring data of settlement observation wereanalyzed,found that improve the theoretical calculation results more close to the observed value,verify the reliability of the improved theory.