Numerical Analysis Of Settlement Of Cement Mixing Pile-Plastic Drainage Plate In Expressway Of Dongting Lake Region

Due to the poor geological conditions and the change of soft foundation treatment methods,the soft settlement expressway-Nanyi Expressway in Dongting Lake District of Hunan Province is prone to be caused by differential settlement at the junction of two different soft foundation treatment methods of expressway cement mixing piles an d plastic drainage plates.Pavement cracks,vehicle bumps,and even cliff-type settleme nts have seriously affected vehicle safety.Therefore,it is urgent to study the effect of these two soft foundation treatment measures on settlement control.This paper starts with the post-construction settlement index of the roadbed top,u ses field monitoring and finite element numerical simulation to analyze the influence f actors of the two soft ground treatment measures on the subgrade settlement after con struction,and uses factor analysis and SPSS software to analyze The relationship betw een the combined parameters of the cement mixing pile and the plastic drainage plate and the post-construction settlement of the top of the roadbed is analyzed to obtain t he corresponding regression equation,which provides data support for the optimal desi gn of the transition section of the soft foundation treatment.The main research results are as follows:According to the existing research results of the transition section of soft foundati on treatment and the actual situation on site,it is proposed to analyze different soft f oundation treatment measures based on the settlement of the top of the roadbed after construction.Based on the on-site settlement monitoring and deep foundation horizontal displac ement monitoring data,the two foundation treatment methods are analyzed to obtain t he settlement law of the two different foundation treatment methods of pile-slab and t he deep foundation horizontal displacement law.Then use the hyperbolic method to pr edict the settlement of the two foundation treatment methods after construction,and co mpare with the numerical simulation results to verify the reliability of the numerical s imulation results.The parameters required for numerical simulation were obtained using indoor triax ial tests.Through the finite element numerical simulation,the influence factors of plas tic drainage plates and mixing piles on the settlement of soft ground were analyzed.T he settlement control effects of the two foundation treatment methods were compared t o determine the subgrade.The key factors influencing the post-construction settlement are the length of the cement mixing pile,the distance between the piles,the distance between the plastic drainage plates and the filling height of the subgrade.Orthogonal test combined with SPSS data analysis software was used to analyze t he key factors of these two types of foundation treatment measures to obtain regressio n equations about the post-construction settlement of the top of the subgrade,and the regression equations were used to calculate the corresponding subgrades under different geological conditions of Dongting Lake geological conditions.The top surface settled after work.Then the regression equation is used to provide data support for the opti mization of the transition section of the pile-slab soft foundation treatment based on t he recommended value of the differential settlement of the expressway and the allowa ble value of the settlement slope difference.