Research On Rivet Pile Composite Foundation Of Embankment Widening Project

Highway widening on soft soil foundation is a new subject in highway engineering.Composite foundation is a kind of foundation treatment method of soft foundation treatment.In widening project,the new and old embankment have differential settlement.The domestic and foreign engineering technical personnel have conducted a large number of engineering practice,to solve the negative influence of the differential settlement in engineering.Although we has obtained some valuable experience in completed engineering,the related theoretical achievements are less,no systematic regulations,new and old roadbed settlement characteristics understand a little,and need further research.In this passage,the author make system research of the settlement characteristics of new and old embankment,it exampled by Caofeidian coastal highway expansion project as the background,from the practical problems on soft soil foundation,and use supper numerical simulation method based on ABAQUS.The main contents are as follows:1,Analysis the field geological situation,Through drilling and sampling,indoor test,get the soft soil geological materials.Due to the long time of consolidation,pore ratio of old roadbed soil decreases 4.86%,preconsolidation pressure has been significantly improved,2.82%.Then,the soft soil reinforcement was carried out on the site of the field engineering test section,by means of the settlement tube monitoring,The maximum value is 54.21 mm.2,Through the finite element simulation,analysis transfer process of rivet pile load in group pile composite foundation,with regard to the distribution of the axial force,get the settlement data before and after filling pile load.Compared with the field monitoring data,the maximum value of the settlement is 73.24 mm,40.6% more than the value of on-site monitoring.3,The additional settlement of the ground surface and the additional displacement.The influence of the size of the pile cap,and the height of embankment fill on the settlement characteristics of the widened embankment are analyzed at the same time.Results show: The bigger the pile cap,the smaller the settlement of composite foundation,within a certain range,However,after reaching a certain value,the settlement is almost unchanged,the best length of pile cap side is 1m t.With the increase of the height of embankment fill,the greater the difference is.