| The mechanical properties of loess are closely related to the unique pore fabric of-loess.Accurately obtaining quantitative information on the pore fabric of undisturbed loess is a fundamental prerequisite for understan,ding the relationship between loess fabric and function and the intrinsic mechanism of the process.There are a large number of vertical macropores in loess,and the vectorization of vertical macropores in loess is the basis and difficulty of in-depth study of structural constitutive relations of loess.In this paper,the industrial CT is used to scan the undisturbed Q2 loess of'Jingyang,and the 3D spatial distribution,model of loess macropores is established.Based on this,a loess large pore bead chain filling method is proposed and the corresponding software is developed.The system uses the obtained bead chain,filling data to quantitatively analyze the macropores of loess,and characterizes the pore diameter distribution and spatial direction characteristics of a single pore.Furthermore,the?abric tensor and fabric coefficient of loess macr'opores are calculated by stereology technology.The proposed method carries out vectorization characterizatiorn of the macroporous fabric features of loess,which lays a foundation for fiurther research on structural constitutive model of loess.The main research contents and cornclusions of this paper are as follows:1)Using the CT scan image to establish a 3D model of the large pores of the undisturbed loess in Jingyang,and observe the pores in different directions and different parts of the undisturbed loess.The established loess rmacropore model can be used for the study of loess macropores.The model observation results show that'the porosity of the undisturbed.loess volume of Jingyang is larger than 0.13rrvmm3,and the pores with a volume less than 0.13mm:a3 tend to be evenly distributed in the soil.This paper focuses on the vectorization characterization of pores with a volume greater than 0.13 mm3;2)A method of filling the loess macropore beads chain is proposed.The obtained beads chain filling data is used to quantitatively analyze the macropores of loess,and the pore size distribution characteristics and spatial direction characteristics of a single pore are characterized.The beads chain filling method can simplify the pore morphology,facilitate the quantitative statistical pore size and direction data,and then characterize the vectorization characteristics of the loess macropore;3)Using the pore-filled beads chain data,the pore diameter distribution curve and the pore diameter cumulative distribution curve of a single or multiple pores can be drawn.It can be seen from the curve that the pore diameter of the undisturbed loess pores of Jingyang is mainly distributed between 0.2mm and 1.2mm,among which the pore content of 0.4mm pore diameter is the most,the pore content of 1.2mm to 1.6mm pore diameter is small,and the pore content of 1.6mm to 2.5mm pore diameter is the least;4)By fitting the spatial position and pore diameter variation data of the pores by the Fourier series equation,the spatial morphology of the pores can be stored as a database.The function of drawing the pore model and the translational rotation of the pore model can be realized by filling the beads chain data with the macropores of the undisturbed loess of Jingyang.The technology and database can be used to generate a pore model with certain characteristics;5)Filling the beads chain data with pores,the fabric tensor coefficient calculated by the editing program can characterize the anisotropy of the pore spatial distribution.The average porosity of the pore model of the undisturbed loess of Jingyang is calculated to be 0.0065,and the fabric tensor coefficient is 1.9299;6)Integrate the above parts of the calculation process and develop it into a complete software system,which realizes the automatic interactive pore bead filling function.The macropore model in the pores of the undisturbed loess of Jingyang can be established by software,and relevant statistics are obtained. |
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