Influence of curing age on the engineering properties of sisal fiber aeolian sand modified soil
In order to study the effect of curing age on the physical and mechanical activation behavior of sisal fiber aeolian sand modified soil,and to improve the brittle cracking characteristics of cement-stabilized aeolian sand soil,the actual aeolian sand modified soil (95％ aeolian sand+5％ cement) of the high-speed railway embankment in Horqin Sandy Land passed by Tongliao Xinmin North High speed Railway was selected. The sisal fibers of 0％,0.1％,0.2％,and 0.4％ were added,respectively. The resistivity test,longitudinal wave velocity test,and unconfined compressive test were carried out under different curing ages (7,14,21,and 28 d). The test results show that the resistivity and longitudinal wave velocity of aeolian sand modified soil increase with the increase of curing age. The growth is significant in the early stage and tends to be gentle in the later stage. Under standard curing conditions,as the curing age increases (from 7 d to 28 d),the elastic modulus of the aeolian sand modified soil with sisal fiber content in each group increased in the form of logarithmic function. The Poisson's ratio of the aeolian sand modified soil with sisal fiber content in each group shows a slight downward trend. Among them,the Poisson's ratio of the aeolian sand modified soil without sisal fiber decreased greatly (0.315～0.336,a decrease of 6.63％),while the Poisson's ratio of the other three groups of aeolian sand modified soil with sisal fiber decreases slightly (0.300～0.308,a decrease of 2.60％). This indicates that the incorporation of sisal fibers has limited effectiveness in improving the lateral deformation resistance of aeolian sand modified soil. The unconfined compressive strength of aeolian sand modified soil also increases in a parabolic manner with the increase of curing age and fiber content,indicating that the incorporation of sisal fiber can effectively improve the compressive strength and ductility characteristics of aeolian sand modified soil,and mitigate its brittle failure. The research results have certain reference value for the engineering application and theoretical research of aeolian sand modified soil in desert area.
万方数据
维普
