Study On Application Of Foamed Concrete In Filling Engineering Of High And Steep Embankment

With the development of the west,the highway construction in the southwest of China has entered a hot stage.The southwest area is mostly high and steep mountainous area,and there are some difficulties in road construction.At present,the mountain road construction mainly uses gravel,coarse sand or medium sand as the main filling materials,and the slope amount is large,and the embankment support is needed.As a new material,foamed concrete has the advantages of light weight,high strength,self-leveling and vertical filling.Based on the reconstruction and expansion project of G354 Shiqian Xiangshuyuan to Heba Highway,this thesis studies the bearing characteristics of foamed concrete in filling engineering of high and steep embankment by means of laboratory test,numerical simulation,theoretical calculation and field monitoring.The theoretical basis and practical reference are provided for the application of foamed concrete in filling engineering of steep slope terrain in mountainous areas.The main research contents and conclusions are as follows:(1)Field sampling of foamed concrete with different densities was conducted on site.Through laboratory tests,the compressive and bending properties of foamed concrete with different densities and curing ages were analyzed.the results show that the foam concrete compressive strength and flexural strength and density of obvious positive correlation,and determine the density of foam concrete used in engineering construction level of 700 kg/m~3.(2)the engineering section characteristics and project design are introduced,and through the finite element software Midas GTS a numerical simulation of the whole process of foam concrete construction of lightweight foam concrete embankment is analyzed the changes of additional stress and displacement,the results show that the foam concrete embankment integrity is good,compared with the ordinary fill scheme can effectively reduce the settlement.(3)introduced traditional roadbed additional stress and settlement calculation method,combining the characteristics of the foam concrete layered casting to improve the traditional calculation method,the calculation results of the improved are analyzed,and compared with the results of numerical simulation,the calculated results show that the additional stress of the basement and the maximum subsidence value and the results of numerical simulation is roughly same,However,the distribution form of the theoretical settlement curve is quite different from that of the numerical simulation.(4)Field monitoring was carried out on K70+405～K70+455 section of the G354 Shiqian Xiangshuyuan to Heba Highway,and the monitored settlement value was compared with the numerical simulation and theoretical calculation results.The results show that the numerical simulation results are closer to the field monitoring value,and the foundation settlement is very uniform when the foamed concrete is used as the filling material of high and steep embankment.