Study On Numerical Simulation Of Subgrade Reinforcement With Bagged Soil

Highway construction is the artery of China's economic development and an important part of building a convenient,smooth,efficient and safe modern transportation system.As the foundation of highway traffic construction,subgrade is the focus and hot spot of current technical department.Currently,roadbed treatment has become increasingly mature,but how to effectively use roadbed reinforcement technology is still a problem,this model tries to long bag technology applied to the processing of roadbed reinforcement,the technology can effectively improve the bearing capacity of subgrade,reduce investment cost and green environmental protection,environmental pollution-free,conforms to our country put forward the "safe,convenient,efficient,green" modern integrated transport system construction standards.The project example used in this paper is the second highway channel project of wuhan tianhe airport.Based on the field observation data of k12+300 section in the S6 contract section,FLAC3 D software was used to conduct numerical modeling and analysis on the reinforcement method of treating packaged soil as subgrade,and the model size was established in accordance with the actual project 1:1.K12+300 section of fill construction,establish four groups of different layers of tile put bags of improved soil roadbed model,namely,tile layer 10 bags,20,30,40 layer subgrade treatment model 1 group and the contrast of no bagged soil subgrade model processing,according to the results of numerical simulation analysis for soil bags after reinforcement embankment settlement deformation and bearing capacity of change.It is found that compared with the model of subgrade without bag soil treatment,the improved subgrade with bag soil treatment has good bearing capacity,and with the increase of the number of bag soil treatment,the subgrade bearing capacity is also improved,and the treatment scheme of tiled 40 floors can achieve the best effect.When the soil bag is subjected to stress and deformation,the tension generated on the surface of the bag ACTS as a constraint on the loose soil in the bag,which can effectively control the lateral displacement and deformation of soil,inhibit the diffusion of effective stress into the roadbed,and thus provide a higher bearing capacity.In order to further study the influence of bagged soil on the stability and bearing capacity of subgrade,three improved subgrade models of bagged soil with different sections,namely,single-arch subgrade treatment model,double-arch subgrade treatment model and three-arch subgrade treatment model,were established under the condition that the quantity of bagged soil in 40 layers of tile is kept unchanged.According to the numerical simulation results show that under the condition of same soil bags quantity,according to the arch structure mechanics characteristics of the soil by the accumulation of traditional bagged arch structure accumulation form,multiple arch section stress is superior to single arch section,compared with the traditional form of tile,theshear strain of soil are reduced,destroy the lowest risk,performance for the bearing capacity of subgrade and roadbed the decrease of the total settlement and uneven settlement,which are three of the arch section is the optimal treatment scheme.Based on the above research results,the feasibility of using bag soil for roadbed reinforcement treatment is illustrated,which meets the control requirements of roadbed quality and has certain theoretical support and reference value for practical engineering.