Study On Reinforcement Effect And Application Technology Of The Geogrid In The Highway Widening

In the construction of highway reconstruction and expansion projects,geogrid(grid room)has been widely used as a measure to control roadbed stability,but there have been many controversies regarding its use in controlling the differential settlement of old and new roadbeds,including control effects and the number of layers installed.Many problems such as the location,location,and so on,resulting in the use of the technology changes in the design of the program,the difference in the control effect of differential settlement and economic differences,and serious inadequacy to adapt to the current development needs of large-scale development of the road.In order to solve this problem,this article through the indoor test,field test and theoretical analysis,studied the difference of the internal stress and deformation law of the grille and the different level of the grille subgrade in different foundation subsidence modes,and analyzed the geogrid to alleviate the differential settlement.Contributing degree,a reasonable geotechnical grid is laid in the roadbed,and a FLAC3D calculation software is used to analyze the stress of the pavement structure,and the application parameters of the geogrid in the pavement structure are obtained;and the monitoring and analysis of the reconstruction and expansion of the Jinan-Qingdao Expressway is carried out.The optimal laying method for the geogrid used in the reconstruction and expansion of Jiqing high-speed is obtained.According to the analysis of experimental and numerical simulation results,the following main conclusions are obtained:.(1)Through investigation and analysis,it is suggested that there may be two major subsidence modes such as equal settlement and non-uniformity in road widening.In order to reveal the effect of geogrid reinforcement and the applicable layers and layers,a geogrid-reinforced embankment model test device was designed and manufactured.The study on the mechanics and deformation characteristics of embankment reinforced with geogrids under different differential settlements was carried out,and it was proposed that the geogrid(room)has certain effect on the control of embankment settlement.(2)Through carrying out reinforced subgrade model test and field test analysis,it is proposed that the differential settlement between the old and new subgrade will cause soil arching in the widening of the subgrade and the stress concentration at the bottom of the overlap,resulting in incoherent deformation of the embankment and reducing the top of the roadbed.Settlement amount,which reveals the application mechanism of geogrid control to widen differential settlement of embankment.(3)Through the model test and theoretical analysis,it is proposed that the settlement control effect of reinforced subgrade has a more significant relationship with the laying of geogrid,the effect of the number of grid layers is small,and the grid is laid on the bottom of the embankment to better control the differential settlement..(4)In view of the differential settlement pattern existing at the top of the roadbed,the mechanical properties of the geogrid-reinforced pavement structure were studied using numerical analysis methods,the application mechanism of the geogrid-reinforced pavement structure was revealed,and the addition under different differential settlement patterns was clarified.