CCPDI-IMPM method for large deformation analysis of saturated porous medium

Abstract

The invention provides a CCPDI-IMPM method for large deformation analysis pf a saturated porous medium based on a u-p control equation of a generalized Biot theory and a convective particle domain interpolation technology, and the method comprises saturated porous medium large deformation consolidation process analysis and saturated porous medium large deformation dynamic process analysis. According to the method, an implicit time integral strategy is adopted to overcome the defect that a traditional explicit material point method is limited by a critical time step length, and particularly, the calculation efficiency is remarkably improved when a quasi-static problem is solved; and the grid boundary smooth interpolation advantage of the CPDI and the Euler-Lagrangian description advantage of the implicit substance point method are combined, so that compared with the traditional FEM, the calculation performance is more stable when large deformation and extremely large deformation are processed. The invention further provides a method for expanding the substance penalty factor, and the method is used for processing the boundary condition of the fluid-solid coupling system more simplyand accurately.

Description

technical field

[0001] The invention belongs to the technical field of computational mechanics, and in particular relates to a CCPDI-IMPM method for large deformation analysis of saturated porous media. Background technique

[0002] Saturated porous media is a heterogeneous porous material that widely exists in nature, which is composed of a deformable solid skeleton and a pore fluid filling it. In recent decades, due to the complex mechanical properties of saturated porous media, researchers have paid close attention to them, and have been widely used in geotechnical engineering, bioengineering and many other fields. Reliable simulation results can be obtained through numerical simulation, and then the functionality and safety of porous structures in actual engineering applications can be effectively evaluated, which has produced many aspects such as related geological disaster prevention, safe and efficient production, and human health protection. important meaning. For ...

Examples

Embodiment 1

[0166] (1) Example 1: Analysis of large deformation consolidation process in saturated porous media (attached Figure 3-8 )

[0167] Such as image 3 As shown, the first embodiment is the problem of structural deformation and internal fluid flow evolution under the vertical loading of the upper middle of the two-dimensional saturated rectangular soil block under the assumption of plane strain. Such as image 3 As shown in (a), the size of the rectangular soil block structure is 40m×25m, the upper and lower boundaries of the structure are both impermeable boundaries, and the lower boundary has fixed degrees of freedom in the horizontal and vertical directions, while the left and right boundaries are p = 0 freely penetrates the boundary, and both fix the degree of freedom in the horizontal direction. For the CCPDI-IMPM proposed by the present invention adopts a discrete model of 80×50 material points, the FEM correspondingly divides the model into 40×25 finite elements. This...

Embodiment 2

[0172] (2) Embodiment two: large deformation dynamic process analysis of saturated porous media (attached Figures 9 to 13 )

[0173] Such as Figure 9 As shown, the second embodiment is the analysis of the vertical loading dynamic problem of the two-dimensional saturated square soil block under the assumption of plane strain. Such as Figure 9 As shown in (a), the size of the soil block structure is 10m×10m, the upper boundary of the structure is set as p=0 free permeable boundary, the left, right and lower boundaries are all non-permeable boundaries, and the lower boundary is fixed and the vertical direction is free degrees, the left and right boundaries are fixed horizontal degrees of freedom. Both the CCPDI-IMPM proposed by the present invention and the comparative algorithm CCPDI-EMPM adopt a discrete model of 40×40 material points, and the FEM correspondingly divides the model into 20×20 finite elements. This embodiment adopts F=1.5×10 7 Pa and F=2.4×10 7 Pa two wo...

technical field

[0001] The invention belongs to the technical field of computational mechanics, and in particular relates to a CCPDI-IMPM method for large deformation analysis of saturated porous media. Background technique

[0002] Saturated porous media is a heterogeneous porous material that widely exists in nature, which is composed of a deformable solid skeleton and a pore fluid filling it. In recent decades, due to the complex mechanical properties of saturated porous media, researchers have paid close attention to them, and have been widely used in geotechnical engineering, bioengineering and many other fields. Reliable simulation results can be obtained through numerical simulation, and then the functionality and safety of porous structures in actual engineering applications can be effectively evaluated, which has produced many aspects such as related geological disaster prevention, safe and efficient production, and human health protection. important meaning. For ...

Examples

Embodiment 1

[0166] (1) Example 1: Analysis of large deformation consolidation process in saturated porous media (attached Figure 3-8 )

[0167] Such as image 3 As shown, the first embodiment is the problem of structural deformation and internal fluid flow evolution under the vertical loading of the upper middle of the two-dimensional saturated rectangular soil block under the assumption of plane strain. Such as image 3 As shown in (a), the size of the rectangular soil block structure is 40m×25m, the upper and lower boundaries of the structure are both impermeable boundaries, and the lower boundary has fixed degrees of freedom in the horizontal and vertical directions, while the left and right boundaries are p = 0 freely penetrates the boundary, and both fix the degree of freedom in the horizontal direction. For the CCPDI-IMPM proposed by the present invention adopts a discrete model of 80×50 material points, the FEM correspondingly divides the model into 40×25 finite elements. This...

Embodiment 2

[0172] (2) Embodiment two: large deformation dynamic process analysis of saturated porous media (attached Figures 9 to 13 )

[0173] Such as Figure 9 As shown, the second embodiment is the analysis of the vertical loading dynamic problem of the two-dimensional saturated square soil block under the assumption of plane strain. Such as Figure 9 As shown in (a), the size of the soil block structure is 10m×10m, the upper boundary of the structure is set as p=0 free permeable boundary, the left, right and lower boundaries are all non-permeable boundaries, and the lower boundary is fixed and the vertical direction is free degrees, the left and right boundaries are fixed horizontal degrees of freedom. Both the CCPDI-IMPM proposed by the present invention and the comparative algorithm CCPDI-EMPM adopt a discrete model of 40×40 material points, and the FEM correspondingly divides the model into 20×20 finite elements. This embodiment adopts F=1.5×10 7 Pa and F=2.4×10 7 Pa two wo...

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