| Bubble mixed light soil is a lightweight geotextile material fonned by mixing raw material soil,curing material,bubble(or foam slurry)and water and then solidified,and all soil mechanics parameters can be adjusted by changing mix proportion,Which can be used in the construction of retaining walls backfill,soft ground reinforcement has been opened to widening of roads and other projects.At the same time,with the economic and technological development,it is a major trend to replace the existing building materials with new materials of higher performance,economy and environmental protection.As an abandoned resource,how to comprehensively and scientifically and efficiently use fly ash as a waste resource,it is an important issue to apply it to civil engineering construction.Abroad has made a lot of research results in the field of light soil research,but the research in our country is not enough,the research of dynamic characteristics is even more lacking.In this paper,the fly ash foam mixed light soil is applied to the foundation,through the density test,direct shear test,indoor dynamic triaxial test and resonant column test,This paper analyzes the effect of using light clay mixed light soil and fly ash mixed light soil with clay as raw material soil,cement and fly ash as curing agent,and foaming agent as lightweight material as foundation materials for treatment,and their feasibility of application in engineering.The main work done in this paper and the achievements made are as follows:1)The density of mixed light soil made of air bubble and light fly ash mixed with fly ash was tested to analyze the development and variation regularity of two mixed light soil density.The influence of cement content,fly ash content and air bubble content on density was analyzed.2)The effects of cement content,bubble content and fly ash content on shear strength of two mixed lightweight soils under different normal stresses(100kPa,200kPa,300kPa,400kPa)were analyzed by direct shear test indoor.We got the best alternative range of fly ash.3)The indoor dynamic triaxial test is adopted to analyze the relationship between the dynamic stress and the destructive vibration frequency of the two mixed light earths and the influence of confining pressure on the dynamic stress.The dynamic strengths of the two mixed lightweight earths at different vibration frequencies are determined,And dynamic cohesion(Cd)and dynamic friction coefficient(?d)under different vibrations are also determined,the effects of confining pressure,seismic grade(equivalent vibration time),cement content,bubble content and fly ash content on soil dynamic strength were analyzed.Analysis of static and dynamic strength parameter cp,Cd relationship of changes;4)The relationship between shear modulus,dynamic shear strain and damping ratio and dynamic shear strain of two kinds of mixed lightweight soils under dynamic action was analyzed by indoor resonant column test.The correlation between dynamic shear modulus and damping ratio and dynamic shear strain of two mixed light soil is given.The effects of cement content,bubble content and fly ash content on dynamic shear modulus and damping ratio are analyzed.And get the best alternative range of fly ash. |
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