CN113505505A - Mixed grid finite element analysis method for simulating large-deformation continuous penetration process - Google Patents

Mixed grid finite element analysis method for simulating large-deformation continuous penetration process Download PDF

Info

Publication number
CN113505505A
CN113505505A CN202110676020.0A CN202110676020A CN113505505A CN 113505505 A CN113505505 A CN 113505505A CN 202110676020 A CN202110676020 A CN 202110676020A CN 113505505 A CN113505505 A CN 113505505A
Authority
CN
China
Prior art keywords
soil
finite element
under
soil body
penetration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110676020.0A
Other languages
Chinese (zh)
Inventor
窦锦钟
孙旻
韩磊
冉岸绿
吴剑秋
袁青云
熊国军
方兴杰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Construction Eighth Engineering Division Co Ltd
Original Assignee
China Construction Eighth Engineering Division Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Construction Eighth Engineering Division Co Ltd filed Critical China Construction Eighth Engineering Division Co Ltd
Priority to CN202110676020.0A priority Critical patent/CN113505505A/en
Publication of CN113505505A publication Critical patent/CN113505505A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/20—Design optimisation, verification or simulation
    • G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/10—Geometric CAD
    • G06F30/13—Architectural design, e.g. computer-aided architectural design [CAAD] related to design of buildings, bridges, landscapes, production plants or roads
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Theoretical Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Evolutionary Computation (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Computational Mathematics (AREA)
  • Civil Engineering (AREA)
  • Mathematical Analysis (AREA)
  • Mathematical Optimization (AREA)
  • Pure & Applied Mathematics (AREA)
  • Architecture (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)

Abstract

The invention relates to a mixed grid finite element analysis method for simulating a large-deformation continuous injection process, which comprises the following steps of: establishing a finite element model for the penetration component and the soil body to be penetrated, and dividing the finite element model of the soil body into a near component area adopting a total stress method and a far component area adopting an effective stress method; acquiring effective stress soil parameters of a far component area, and deducing total stress soil parameters of a near component area according to the effective stress soil parameters on the basis of the assumption that shearing and volume effects of isotropic soil in an elastic deformation stage are decoupled under a total stress method and an effective stress method; and carrying out finite element simulation on the process of continuously penetrating the soil body in large deformation according to the finite element models of the penetration component and the soil body, the effective stress soil body parameter and the total stress soil body parameter. The invention can simultaneously solve the problems of grid distortion and pore water pressure effect in the simulation of continuous finite element injection of the injection component in the saturated soft soil.

Description

Mixed grid finite element analysis method for simulating large-deformation continuous penetration process
Technical Field
The invention relates to the field of constructional engineering, in particular to a mixed grid finite element analysis method for simulating a large-deformation continuous injection process.
Background
In the field of geotechnical engineering, when finite element simulation is carried out on the continuous injection process of the tubular pile in saturated soft soil, the problem of grid distortion caused by overlarge deformation of a soil model grid is faced. At present, common finite element methods for processing the problem of large-deformation continuous penetration are mainly divided into three types:
(1) lagrangian method. The method adopts a finite element model in an effective stress form, can consider the influence of pore water pressure effect, but cannot solve the problem of grid distortion caused by large deformation of a soil body, and needs to be combined with a round hole expansion theory, a pre-drilled pile or a casing method so as to solve the problem of grid distortion in a limited way. However, the round hole expansion theory has the defects that the method cannot reflect the sinking mechanism of the pile and cannot consider the dynamic sinking characteristic; the method has the defects that the method can only calculate the sinking depth of a small pile and cannot well simulate the dynamic response of a soil body; the defect of the casing method is that the movement of soil bodies on two sides of the pile bottom is limited due to the existence of the rigid pipe, and the pile-soil interaction mechanism is influenced.
(2) ALE (Arbitrary Lagrangian-Eulerian) method. Although the capability of handling large deformation is stronger than that of Lagrange method, because the method adopts a finite element model in a total stress form, the influence of pore water pressure effect is ignored, and the method grid can not be split and is only suitable for closed pile type, a certain initial embedding depth is usually preset for avoiding overlarge deformation of the model grid when the model grid is penetrated from the ground surface, and a zipper method is adopted for simulating a continuous penetration process, namely, a superfine friction-free rigid pipe penetrating through a pile body and a soil body model is arranged at the pile tip, but the movement of the soil body at two sides of the lower part of the pile tip is blocked due to the existence of the rigid pipe, so that the interaction mechanism between the pile and the soil is influenced.
(3) The CEL (Coupled Eulerian-Lagrangian) method. Although the method thoroughly overcomes the problem of large deformation of the grid and is suitable for penetration simulation of various pile types, the method also adopts a finite element model in a total stress form, neglects the influence of pore water pressure effect, is only suitable for a three-dimensional model, and needs to arrange a partial empty grid (without distributing materials) on the upper part of the soil body boundary to simulate the uplift phenomenon of the soil body surface.
Compared with the effect of continuous penetration of the tubular pile in sandy soil, the effect of continuous penetration of the tubular pile is mainly embodied in soil deformation, and for saturated soft soil, the effect of continuous penetration of the tubular pile is also embodied in the generation of soil body ultra-pore water pressure (EPWP) in a penetration stage and the dissipation of the EPWP after the penetration is finished, so that the safety of buildings in a certain range around the pile can be threatened, the effective stress state close to the soil body can be changed, and the self penetration resistance in the penetration stage and the bearing capacity aging of the pile foundation after the penetration is finished are influenced. Therefore, when finite element simulation is carried out on the continuous tubular pile injection process in the saturated soft soil, the problem of grid distortion caused by large deformation of a soil body needs to be solved, and the pore water pressure effect needs to be considered, and under the condition, any method cannot meet the actual requirement.
Disclosure of Invention
In order to solve the problems, the invention provides a mixed grid finite element analysis method for simulating a large-deformation continuous penetration process, which can simultaneously solve the problems of grid distortion and pore water pressure effect in the simulation of continuous penetration finite elements of a penetration component in saturated soft soil.
The invention is realized by the following scheme: a mixed grid finite element analysis method for simulating a large-deformation continuous penetration process comprises the following steps:
establishing a finite element model for a penetration component and a soil body to be penetrated, and dividing the finite element model of the soil body into a near component area adopting a total stress method and a far component area adopting an effective stress method;
acquiring effective stress soil parameters of a far component region, and deducing total stress soil parameters of a near component region according to the effective stress soil parameters on the basis of the assumption that shearing and volume effects of isotropic soil in an elastic deformation stage are decoupled under a total stress method and an effective stress method;
and carrying out finite element simulation on the process of continuously penetrating the large deformation into the soil body according to the finite element models of the penetration component and the soil body, the effective stress soil body parameter and the total stress soil body parameter.
The invention further improves the method for analyzing the mixed grid finite element for simulating the large-deformation continuous penetration process, which comprises the following steps:
the effective stress soil parameters comprise a shear modulus G 'under a drainage condition and an elastic modulus E' under a drainage condition, and the total stress soil parameters comprise a shear modulus G under a non-drainage conditionuAnd modulus of elasticity E under non-draining conditionsu；
The step of deducing the total stress soil parameter of the near component area according to the effective stress soil parameter comprises the following steps:
establishing a relation E ' of an elastic modulus E ' under a drainage condition and a shear modulus G ' under the drainage condition as 2G ' (1+ v ') (1), wherein v ' is a Poisson ' ratio under the drainage condition;
establishing the modulus of elasticity E under non-draining conditionsuAnd shear modulus G under non-draining conditionsuRelation of (E)u＝2Gu(1+vu) (2) wherein vuFor a Poisson's ratio under non-draining conditions, the Poisson's ratio under non-draining conditions v under a total stress algorithmuIs a fixed value;
based on the assumption, the shear modulus G under the condition of no drainage is obtaineduRelation G with shear modulus G' under drainage conditionsu＝G′＝G(3)；
Substituting relational expression (1) and relational expression (2) into relational expression(3) In (2), the modulus of elasticity E under the condition of no water drainage is obtaineduThe relation with the elastic modulus E' under the drainage condition is as follows:
Figure BDA0003121156970000031
the invention further improves the method for analyzing the mixed grid finite element for simulating the large-deformation continuous penetration process, which comprises the following steps:
the total stress soil parameters also comprise the saturated volume weight of the soil and the static side pressure coefficient K under the condition of no drainage1，K1＝vu/(1-vu)；
The effective stress soil parameters further comprise the effective volume weight of the soil and the static side pressure coefficient K under the drainage condition2，
Figure BDA0003121156970000032
Wherein, K0ncV '/(1-v') or
Figure BDA0003121156970000033
K0ncIs the static side pressure coefficient of the normally consolidated soil body, OCR is the super consolidation ratio of the soil body,
Figure BDA0003121156970000034
is the effective internal friction angle of the soil body.
The invention further improves the mixed grid finite element analysis method for simulating the large-deformation continuous injection process, wherein the injection component is a tubular pile, and the near component area is R distance from the pile bodyxA region within a multiple of the pile radius, the distal member region being a region outside the proximal member region, wherein RxIs [0.1 to 0.6 ]]，RxInversely related to the pile radius.
The invention further improves the mixed grid finite element analysis method for simulating the large-deformation continuous injection process, wherein the grid units of the soil finite element model in the far component area adopt Lagrange algorithm, when the injection component is in a closed type, the grid units of the soil finite element model in the near component area adopt ALE algorithm or CEL algorithm, and when the injection component is in an open type, the grid units of the soil finite element model in the near component area adopt CEL algorithm.
The invention further improves the mixed grid finite element analysis method for simulating the large-deformation continuous injection process, and when the grid unit of the soil finite element model of the near component area adopts a CEL algorithm, a hollow grid area for simulating the soil surface bulging phenomenon is arranged at the upper part of the near component area when the finite element model is established on the soil.
The invention further improves the method for analyzing the finite element of the mixed grid for simulating the large-deformation continuous penetration process, wherein when the finite element simulation is carried out on the large-deformation continuous penetration process of the soil body, the penetration component is a rigid body which can not generate self deformation in the continuous penetration process.
The mixed grid finite element analysis method provided by the invention solves the problem of grid distortion by setting a near component region (namely a region near a pile-soil contact surface) as a finite element grid based on a total stress method and adopting an ALE algorithm or a CEL algorithm; the remote component area is set to be a grid adopting an effective stress method, and the Lagrange algorithm is adopted, so that the calculation of the water pressure of the soil body super-pore caused by the penetration process can be realized; the analysis result is more accurate, and the influence of the continuous pipe pile penetration process on the adjacent underground structure is convenient to study; the method is suitable for different injection members, injection modes and site environments, has good economic benefits and has great popularization value.
Drawings
FIG. 1 is a flow chart of a mixed mesh finite element analysis method for simulating a large deformation continuous penetration process according to the present invention.
FIG. 2 is a schematic diagram showing the position relationship among regions of a finite element model of a soil body in the process of simulation penetration based on the method of the invention.
FIG. 3 is a perspective view of a finite element model constructed by the method of the present invention for the first embodiment.
Fig. 4 shows a cross-sectional view a-a of fig. 3.
FIG. 5 is a graph showing a comparison of time course curves of calculated values and measured values of water pressure exceeding pores at different depths, which are obtained by the simulation of the first embodiment according to the method of the present invention.
Fig. 6 shows a comparison of calculated and dissipated water pressure over time values of pile-surrounding soil body excess pore space and measured values when the method of the invention is adopted to simulate the first embodiment.
Detailed Description
Because the traditional Lagrange algorithm adopts a finite element model in an effective stress form, the influence of the pore water pressure effect can be considered, but the problem of grid distortion caused by large deformation of a soil body cannot be solved, and the traditional CEL or ALE algorithm adopts a finite element model in a total stress form, so that the influence of the pore water pressure is ignored. For saturated soft soil, the problem of grid distortion is solved, and the effect of excess pore water pressure is also considered, because the effect threatens the safety of buildings in a certain range around a penetration member, and changes the effective stress state of the adjacent soil body, thereby influencing the self penetration resistance in the penetration stage and the bearing capacity aging of the foundation after the penetration is finished.
Based on the problems, the invention provides a mixed grid finite element analysis method for simulating a large-deformation continuous injection process, which can realize water and soil coupling transient analysis under the conditions of complete non-drainage and complete drainage on the premise of effectively solving the problem of large deformation of a grid, and can also research the influence of the continuous injection process on adjacent underground structures.
The method for analyzing the mixed mesh finite element for simulating the large deformation continuous penetration process is further described with specific embodiments and drawings.
Referring to fig. 1 and fig. 2, fig. 1 shows a flow chart of a mixed grid finite element analysis method for simulating a large deformation continuous penetration process according to the invention, and fig. 2 shows a schematic diagram of the position relationship of each region of a soil finite element model in the simulation penetration process based on the method of the invention.
A mixed grid finite element analysis method for simulating a large-deformation continuous penetration process comprises the following steps:
step S1, establishing a finite element model for the penetration member 1 and the soil body 2 to be penetrated, and dividing the finite element model of the soil body 2 into a near member region 21 adopting a total stress method and a far member region 22 adopting an effective stress method.
Specifically, considering that friction occurs when the penetration member 1 is in contact with the soil body 2 during the penetration process of the penetration member 1, and the soil body 2 is subjected to shear deformation under the friction action of the two, when finite element simulation is performed on the continuous penetration process, the soil body in the area near the friction contact surface (i.e. the near component area 21) is prone to grid distortion due to large deformation, and compared with the area near the friction contact surface, the influence of the two friction actions on the soil body in the far component area 22 is negligible, and the soil body in the far component area 22 is mainly subjected to lateral extrusion action. Therefore, in the step of establishing the finite element model, the soil model of the near component region 21 is set as a finite element grid based on a total stress method capable of effectively solving the grid distortion problem, the soil model of the far component region 2 is set as a finite element grid based on an effective stress method capable of considering the pore water pressure effect, and the corresponding soil excess pore water pressure can be set to be calculated by adopting a Biot consolidation theory. In this embodiment, the Lagrange algorithm is adopted for the grid elements of the soil finite element model in the far component region 22, the ALE algorithm or the CEL algorithm is adopted for the grid elements of the soil finite element model in the near component region 21 when the penetration component 1 is in the closed type, and the grid elements of the soil finite element model in the near component region 21 only adopt the CEL algorithm because the grid of the ALE algorithm cannot be split when the penetration component 1 is in the open type. Further, when the grid cells of the finite element model of the soil in the near component region 21 adopt the CEL algorithm, the soil plug effect during the continuous penetration of the open type penetration component can be simulated, but when the finite element model is established for the soil 2, a hollow grid region 23 (i.e., a hollow grid without material distribution) for simulating the soil surface swelling phenomenon is arranged at the upper part of the near component region 21.
For the penetration member with larger major diameter, the continuous penetration process can cause large deformation of soil body, further cause the deformity of the calculation grid, and cause difficult convergence or even incapability of convergenceTherefore, the penetrating member in the present embodiment may be a pipe pile, a pile shoe, a static sounding member, a dynamic consolidation member, a pipe jacking member, or the like, which has a relatively large major diameter. Taking a pipe pile as an example, based on the above concept, when dividing the near component region 21 and the far component region 22, the distance R from the pile body is usedxThe region within the range of the multiple pile radius is defined as a proximal member region 21, and the region outside the proximal member region 21 is defined as a distal member region 22, wherein R isxPreferably [0.1 to 0.6 ]]，RxAnd the negative correlation is formed between the diameter of the pile and the diameter of the pile, and the grid distortion problem and the pore water pressure effect problem can be effectively guaranteed to be solved simultaneously through the division.
Step S2, obtaining effective stress soil parameters of the far component region 22, and deriving total stress soil parameters of the near component region 21 according to the effective stress soil parameters based on the assumption that the shearing and volume effects of the isotropic soil at the elastic deformation stage are decoupled under the total stress method and the effective stress method at the same time.
Specifically, the effective stress soil parameters comprise a shear modulus G 'under a drainage condition and an elastic modulus E' under a drainage condition, and the total stress soil parameters comprise a shear modulus G under a non-drainage conditionuAnd modulus of elasticity E under non-draining conditionsu；
Establishing a relation E ' of an elastic modulus E ' under a drainage condition and a shear modulus G ' under the drainage condition as 2G ' (1+ v ') (1), wherein v ' is a Poisson ' ratio under the drainage condition;
establishing the modulus of elasticity E under non-draining conditionsuAnd shear modulus G under non-draining conditionsuRelation of (E)u＝2Gu(1+vu) (2) wherein vuThe Poisson ratio under the condition of no drainage is achieved, the total stress method does not consider the pore water pressure effect, the soil body is a single-phase medium and is in an incompressible state, and therefore the Poisson ratio v under the condition of no drainage is achievedu0.5. However, when the Poisson ratio v isuWhen the volume modulus K of the soil body is 0.5, the value of the volume modulus K of the soil body tends to be infinite, which leads to a numerical problem, and therefore, in the present embodiment, the poisson ratio v under the non-drainage condition is set when the finite element analysis is performedu＝0.49；
Based on the assumption that the shearing and volume effects of the isotropic soil body in the elastic deformation stage are decoupled under the total stress method and the effective stress method at the same time, the shearing modulus G under the condition of no drainage can be obtaineduRelation G with shear modulus G' under drainage conditionsu＝G′＝G(3)；
By substituting the relational expressions (1) and (2) into the relational expression (3), the modulus of elasticity E under the water-repellent condition can be obtaineduThe relation with the elastic modulus E' under the drainage condition is as follows:
Figure BDA0003121156970000061
further convert v touSubstituting 0.49 into the relational expression (4) to obtain
Figure BDA0003121156970000062
From there, a correlation is established between the total stress soil parameter and the effective stress soil parameter, and through the correlation, continuity of soil stress at the mixed grid interface B (i.e., the interface between the near component region 21 and the far component region 22) is ensured.
Step S3, carrying out finite element simulation on the large-deformation continuous injection process according to the finite element models of the injection component 1 and the soil body 2, the effective stress soil body parameter and the total stress soil body parameter.
Particularly, the injection mode mainly includes static pressure injection and hammering injection, when carrying out the finite element simulation to static pressure injection process, accomplishes static pressure injection process through applying the displacement curve, when carrying out the finite element simulation to hammering injection process, accomplishes hammering injection process through applying hammering load curve. In addition, in order to improve the calculation efficiency, the penetration member 1 may be a rigid body that does not undergo self-deformation during continuous penetration, and further, it is not necessary to consider the self-deformation of the penetration member during continuous penetration. However, if the deformation of the penetration member 1 itself must be considered, the penetration member 1 may be provided as an elastic body, and if an underground structure 3 exists within a certain range of the penetration member, the underground structure may be provided as an elastic body, and the contact of the underground structure 3 with the adjacent soil body adopts the Coulomb's law of frictional contact.
As a preferred embodiment:
the total stress soil parameters also comprise the saturated volume weight of the soil and the static side pressure coefficient K under the condition of no drainage1＝vu/(1-vu)；
The effective stress soil parameters also comprise the effective volume weight of the soil and the static side pressure coefficient under the drainage condition
Figure BDA0003121156970000071
Wherein, K0ncV '/(1-v') or
Figure BDA0003121156970000072
K0ncIs the static side pressure coefficient of the normally consolidated soil body, OCR is the super consolidation ratio of the soil body,
Figure BDA0003121156970000073
is the effective internal friction angle of the soil body.
Through the improvement, the continuity of the initial total stress of the soil body at the mixed grid interface B is ensured.
The invention uses the concrete embodiment to apply and verify the above-mentioned mixed grid finite element analysis method:
in the first embodiment, the penetration member 1 is a closed tubular pile, the inner and outer diameters of the tubular pile are 203mm and 219mm respectively, the total length is 7.5m, the tubular pile is penetrated into the soil body 2 by a static pressure penetration method, the soil body 2 is saturated soft soil, the average permeability coefficient of the soil layer is 3.5e-10m/s, and the tubular pile is in a slight hypercuring state. Referring to fig. 3 and 4, fig. 3 shows a schematic perspective view of a finite element model created by the method of the present invention for a first embodiment, and fig. 4 shows a cross-sectional view a-a of fig. 3. The finite element model of the soil body 2 adopts a cylindrical full model, the radius of which is 4.0m, and the height of which is 13.6 m. The ALE algorithm is adopted by the soil model grid cells of the near component area 21, and the Lagrange algorithm is adopted by the soil model grid cells of the other areas (namely, the far component area 22).
And (3) completing finite element simulation of the static pressure injection process of the tubular pile by applying a displacement curve to obtain a time course curve of the calculated values of the excess pore water pressure at different depths of the tubular pile, and actually measuring the excess pore water pressure at different depths of the tubular pile to finally obtain a comparison graph of the calculated values and the actually measured values, wherein the calculated values and the actually measured values are consistent as shown in fig. 5. Further, through the finite element simulation, a calculated value of generation and dissipation of the water pressure of the over-hole of the soil body around the pile along with time is obtained, meanwhile, the generation and dissipation of the water pressure of the over-hole of the soil body around the pile along with time are actually measured, and finally, a comparison graph of the calculated value and an actually measured value is obtained, as shown in fig. 6, the calculated value and the actually measured value are kept consistent.
From the above verification, the hybrid mesh finite element analysis method of the present invention is feasible.
Of course, the mixed grid finite element analysis method can also be applied to other examples, such as open tubular piles or other penetration members, hammering penetration modes and the like, and the finite element model of the soil body can adopt a cylindrical full model or a half model and only needs to be adjusted according to actual requirements. The mixed grid finite element analysis method has the advantages of wide practicability, flexible use, good economic benefit and high popularization value.
While the present invention has been described in detail and with reference to the embodiments thereof as illustrated in the accompanying drawings, it will be apparent to one skilled in the art that various changes and modifications can be made therein. Therefore, certain details of the embodiments are not to be interpreted as limiting, and the scope of the invention is to be determined by the appended claims.

Claims (7)

1. A mixed grid finite element analysis method for simulating a large-deformation continuous penetration process is characterized by comprising the following steps:
establishing a finite element model for a penetration component and a soil body to be penetrated, and dividing the finite element model of the soil body into a near component area adopting a total stress method and a far component area adopting an effective stress method;
acquiring effective stress soil parameters of a far component region, and deducing total stress soil parameters of a near component region according to the effective stress soil parameters on the basis of the assumption that shearing and volume effects of isotropic soil in an elastic deformation stage are decoupled under a total stress method and an effective stress method;
and carrying out finite element simulation on the process of continuously penetrating the large deformation into the soil body according to the finite element models of the penetration component and the soil body, the effective stress soil body parameter and the total stress soil body parameter.
2. The method for hybrid mesh finite element analysis for simulating a large deformation continuous penetration process according to claim 1, wherein:
the effective stress soil parameters comprise a shear modulus G 'under a drainage condition and an elastic modulus E' under a drainage condition, and the total stress soil parameters comprise a shear modulus G under a non-drainage conditionuAnd modulus of elasticity E under non-draining conditionsu；
The step of deducing the total stress soil parameter of the near component area according to the effective stress soil parameter comprises the following steps:
establishing a relation E ' of an elastic modulus E ' under a drainage condition and a shear modulus G ' under the drainage condition as 2G ' (1+ v ') (1), wherein v ' is a Poisson ' ratio under the drainage condition;
establishing the modulus of elasticity E under non-draining conditionsuAnd shear modulus G under non-draining conditionsuRelation of (E)u＝2Gu(1+vu) (2) wherein vuFor the Poisson's ratio under non-draining conditions, v, under the total stress methoduIs a fixed value;
based on the assumption, the shear modulus G under the condition of no drainage is obtaineduRelation G with shear modulus G' under drainage conditionsu＝G′＝G (3)；
The elastic modulus E under the water-repellent condition was obtained by substituting the relational expressions (1) and (2) into the relational expression (3)uThe relation with the elastic modulus E' under the drainage condition is as follows:
Figure FDA0003121156960000011
。
3. the method for hybrid mesh finite element analysis for simulating a large deformation continuous penetration process according to claim 2, wherein:
the total stress soil parameters also comprise the saturated volume weight of the soil and the static side pressure coefficient K under the condition of no drainage1，K1＝vu/(1-vu)；
The effective stress soil parameters further comprise the effective volume weight of the soil and the static side pressure coefficient K under the drainage condition2，
Figure FDA0003121156960000021
Wherein, K0ncV '/(1-v') or
Figure FDA0003121156960000022
K0ncIs the static side pressure coefficient of the normally consolidated soil body, OCR is the super consolidation ratio of the soil body,
Figure FDA0003121156960000023
is the effective internal friction angle of the soil body.
4. The method of claim 1, wherein the penetrating member is a pipe pile and the near-member region is a distance R from the pile bodyxA region within a multiple of the pile radius, the distal member region being a region outside the proximal member region, wherein RxIs [0.1 to 0.6 ]]，RxInversely related to the pile radius.
5. The method of claim 1, wherein the latgrange algorithm is used for the mesh elements of the finite element soil model in the far pile area, the ALE algorithm or CEL algorithm is used for the mesh elements of the finite element soil model in the near pile area when the penetration member is closed, and the CEL algorithm is used for the mesh elements of the finite element soil model in the near pile area when the penetration member is open.
6. The method of claim 5, wherein when the grid cells of the finite element model of the soil in the near component region adopt the CEL algorithm, an empty grid region for simulating a soil surface swelling phenomenon is provided at an upper portion of the near component region when the finite element model of the soil is established on the soil.
7. The method according to claim 1, wherein the rigid body is not deformed during the continuous penetration process when performing the finite element simulation on the large deformation continuous penetration process.
CN202110676020.0A 2021-06-18 2021-06-18 Mixed grid finite element analysis method for simulating large-deformation continuous penetration process Pending CN113505505A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110676020.0A CN113505505A (en) 2021-06-18 2021-06-18 Mixed grid finite element analysis method for simulating large-deformation continuous penetration process

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110676020.0A CN113505505A (en) 2021-06-18 2021-06-18 Mixed grid finite element analysis method for simulating large-deformation continuous penetration process

Publications (1)

Publication Number Publication Date
CN113505505A true CN113505505A (en) 2021-10-15

Family

ID=78010385

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110676020.0A Pending CN113505505A (en) 2021-06-18 2021-06-18 Mixed grid finite element analysis method for simulating large-deformation continuous penetration process

Country Status (1)

Country Link
CN (1) CN113505505A (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103870640A (en) * 2014-03-03 2014-06-18 中国海洋石油总公司 Method for evaluating influence of self-elevating drilling ship pile insertion on adjacent jacket platform pile foundation
CN105825012A (en) * 2016-03-16 2016-08-03 上海交通大学 Method for calculating soil horizontal displacement caused by FCEC (Fast Cut Evacuate Construction) construction method
CN110008523A (en) * 2019-03-12 2019-07-12 东南大学 A kind of ground numerical simulation of excavation method for CEL method
CN110135125A (en) * 2019-01-30 2019-08-16 天津大学前沿技术研究院 Numerical analysis method of the drill ship pitching pile to neighbouring grouped piles influence under a kind of horizontal force
CN110321569A (en) * 2018-03-28 2019-10-11 天津大学 It is a kind of to plug the method for numerical simulation influenced on Adjacent Pile Foundation suitable for shoe
JP2020070582A (en) * 2018-10-30 2020-05-07 株式会社不動テトラ Ground displacement suppression method and displacement absorption pile
CN111539140A (en) * 2020-04-17 2020-08-14 山东建筑大学 Modeling method, device and readable storage medium for finite element simulation uniaxial penetration strength test

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103870640A (en) * 2014-03-03 2014-06-18 中国海洋石油总公司 Method for evaluating influence of self-elevating drilling ship pile insertion on adjacent jacket platform pile foundation
CN105825012A (en) * 2016-03-16 2016-08-03 上海交通大学 Method for calculating soil horizontal displacement caused by FCEC (Fast Cut Evacuate Construction) construction method
CN110321569A (en) * 2018-03-28 2019-10-11 天津大学 It is a kind of to plug the method for numerical simulation influenced on Adjacent Pile Foundation suitable for shoe
JP2020070582A (en) * 2018-10-30 2020-05-07 株式会社不動テトラ Ground displacement suppression method and displacement absorption pile
CN110135125A (en) * 2019-01-30 2019-08-16 天津大学前沿技术研究院 Numerical analysis method of the drill ship pitching pile to neighbouring grouped piles influence under a kind of horizontal force
CN110008523A (en) * 2019-03-12 2019-07-12 东南大学 A kind of ground numerical simulation of excavation method for CEL method
CN111539140A (en) * 2020-04-17 2020-08-14 山东建筑大学 Modeling method, device and readable storage medium for finite element simulation uniaxial penetration strength test

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JINZHONG DOU: "Method for estimating initial excess pore pressure during pile jacking into saturated fine-grained soil", 《COMPUTERS AND GEOTECHNICS》, pages 1 - 18 *

Similar Documents

Publication Publication Date Title
Surarak et al. Stiffness and strength parameters for hardening soil model of soft and stiff Bangkok clays
Khoiri et al. Evaluation of deformation parameter for deep excavation in sand through case histories
Chang et al. Consolidation analysis for partly saturated clay by using an elastic–plastic effective stress–strain model
CN110702881B (en) Prediction method of rock-soil material parameter variability result and application thereof
Osaimi et al. Pore-pressure dissipation during excavation
Khanmohammadi et al. Evaluation of performance of piled-raft foundations on soft clay: A case study
Powrie et al. Centrifuge model tests on embedded retaining walls supported by earth berms
Hu et al. Deep penetration of shallow foundations on non-homogeneous soil
CN113505505A (en) Mixed grid finite element analysis method for simulating large-deformation continuous penetration process
CN110377935B (en) Method for predicting change of excess pore water pressure along depth of soil body around pile in pile sinking process
Chen et al. Side resistance of drilled shafts socketed into rocks for serviceability and ultimate limit states
CN114595642B (en) Simplified analysis method for soil slope stability considering rainfall infiltration influence
CN112177061B (en) System and method for monitoring microscopic horizontal deformation under complex geological structure
CN114117592A (en) Method for analyzing grouting water-cement ratio of large-diameter cast-in-place pile based on ANSYS numerical simulation
Liu et al. Numerical Simulation Analysis of Deep Foundation Pit Engineering Based on HS-Small Constitutive Modell
CN115329449B (en) Method for calculating optimal reserved interval of upper and lower sections of piles by reverse self-balancing pile testing method
CN100482897C (en) Self-divergence type herringbone stake
Naji et al. NUMERICAL ANALYSIS FOR CAVITY EFFECT ON ANCHOR PLATE CAPACITY
Chheng et al. 3D Finite Element Modelling of Sheet Pile Wall Excavation: A Case study in Bangkok
Mohsen et al. Negative Skin Friction and Neutral Plan on the Pile in Collapsible Soil: A Review Study
Arafianto et al. Deriving a py curve from lateral pile load tests–Case studies in alluvial OC clays
Zhou et al. Elastic Visco-plastic and Damaging Analysis of Structured Soil
Wang et al. Research on Pile Parameters of Screw Pile based on Horizontal Bearing Capacity
Ni A Study on Pile Setup of Driven Steel Pipe in Edmonton Till
Al-Neami et al. Comparative Study of Bearing Loads for Open Ended Pipe and H-Piles in Sandy Soil

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination