CN110162908B - Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile - Google Patents
Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile Download PDFInfo
- Publication number
- CN110162908B CN110162908B CN201910459458.6A CN201910459458A CN110162908B CN 110162908 B CN110162908 B CN 110162908B CN 201910459458 A CN201910459458 A CN 201910459458A CN 110162908 B CN110162908 B CN 110162908B
- Authority
- CN
- China
- Prior art keywords
- soil
- pile
- saturated
- circle
- soil body
- 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.)
- Active
Links
Images
Classifications
-
- 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
- G06F2119/06—Power analysis or power optimisation
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Geometry (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Theoretical Computer Science (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Computational Mathematics (AREA)
- Architecture (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Pure & Applied Mathematics (AREA)
- Evolutionary Computation (AREA)
- General Engineering & Computer Science (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention discloses a horizontal vibration analysis method for a pipe pile in radial heterogeneous saturated soil, which comprises the steps of taking the coupling effect between solid and liquid phases into consideration by adopting a radial heterogeneous saturated soil model and a Biot porous medium theoretical model, establishing and solving a pile foundation horizontal vibration response model of the radial heterogeneous saturated soil model under a plane strain condition, and obtaining an impedance function of the pipe pile. The plane strain assumption adopted by the method can simply process the relatively complex actual engineering situation, and has clear concept and strong theoretical performance; meanwhile, the coupling effect between solid and liquid phases is considered in the Biot porous medium model, and the Biot porous medium model is closer to the actual working condition than a single-phase medium. The radial heterogeneous performance considers the construction disturbance effect of the soil body around the pile, and can provide theoretical guidance and reference for the research of more complex saturated soil-pile dynamic interaction problems.
Description
Technical Field
The invention relates to the field of civil engineering, in particular to a horizontal vibration analysis method for a radial heterogeneous saturated soil-in-pipe pile.
Background
The study of pile-soil coupling vibration characteristics is a theoretical basis in the engineering technical fields of pile foundation earthquake resistance, earthquake-proof design, pile foundation power detection and the like, and is a hot point problem of geotechnical engineering and solid mechanics all the time.
The research about the saturated soil-pile horizontal coupling vibration problem is developed based on a homogeneous saturated soil medium model, the model regards soil around the pile as homogeneous or longitudinal layering, and in the pile foundation construction process, due to the influences of soil squeezing, loosening and other factors, the properties and parameters of the soil can be changed to different degrees in different ranges around the pile, namely, the radial heterogeneous effect. At the moment, the adoption of a radial heterogeneous saturated soil model is more suitable, and the influence of a pile core soil body on the horizontal vibration of the pipe pile is considered. In addition, the Biot porous medium theoretical model considers the coupling effect between solid and liquid phases, and has more complexity and higher applicability compared with the traditional ideal (single-phase) medium.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a method for analyzing horizontal vibration of a tubular pile in radial heterogeneous saturated soil.
In order to realize the purpose, the technical scheme of the invention is as follows:
the horizontal vibration analysis method for the pipe pile in the radial heterogeneous saturated soil is characterized by comprising the following steps
S1: the following assumptions are introduced, and a vibration model of the radial heterogeneous saturated soil pipe-in-pipe pile under horizontal excitation under the plane strain condition is established:
(1) assuming that the tubular pile is a linear elastic homogeneous uniform-section circular Bernoulli-Euler beam model, neglecting the shear deformation of a pile body, and adopting a fixed support at the pile end;
(2) the soil body around the pile is divided into an inner area and an outer area, the inner area is divided into n circle layers, and the soil body of each circle layer and the pile core soil are homogeneous and isotropic two-phase saturated elastic media;
(3) the pile-soil system vibrates in small deformation, the pile-soil interface is in complete contact without separation and slippage, the pile-soil interface is impervious, the displacement of two sides of the soil interface of each ring layer is continuous, and the stress is balanced;
(4) when the pile foundation horizontally vibrates, the soil around the pile and the pile core soil have no vertical deformation;
s2: establishing a motion equation of saturated soil bodies of all circle layers, a motion equation of pile core soil and a pile body horizontal vibration basic equation under a plane strain condition based on a Biot two-phase medium fluctuation theory;
establishing pile-soil system boundary conditions according to the assumption in the step S1;
s3: using laplace transform to solve the motion equation of the saturated soil body of each circle layer and the motion equation of the pile core soil under the plane strain condition established in the step S2 to obtain the horizontal dynamic impedance of the tubular pile so as to analyze the horizontal vibration of the tubular pile in the radially inhomogeneous saturated soil.
Preferably, in the step S2, the equation of motion of the saturated soil body of each circle layer under the planar strain condition is
The equation of motion of the pile core soil is
The basic equation of horizontal vibration of the pile body is
In the above formulae, the symbols have the following meanings:
j is 1-n, the number sequence of the ring layers is 1, the ring layer adjacent to the tubular pile is numbered, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of a z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is a horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
u rj is the radial displacement of the soil skeleton in the saturated soil body of the jth circle layer u θj Is the circumferential displacement, w, of the soil framework in the j-th circle of saturated soil body rj Is the radial displacement of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework, w θj The circumferential displacement of the fluid in the j-th circle of saturated soil body relative to the soil framework is obtained;
u r0 is the radial displacement of the soil skeleton in the pile core soil, u θ0 Is the circumferential displacement, w, of the soil skeleton in the pile core soil r0 Is the radial displacement of the fluid in the pile core soil relative to the soil skeleton, w θ0 The circumferential displacement of the fluid in the pile core soil relative to the soil framework is obtained;
ρ j =(1-n j )ρ sj +n j ρ fj is the density of the saturated soil body of the jth circle layer, wherein rho fj The density and rho of the fluid in the saturated soil body of the jth circle layer sj The density of soil particles in the saturated soil body of the jth circle layer, n j The porosity of the saturated soil body of the jth circle layer;
ρ 0 =(1-n 0 )ρ s0 +n 0 ρ f0 is the soil mass density of the pile core soil, where p f0 Density, rho, of fluid in the pile core soil body s0 Is the density of soil particles in the pile core soil body, n 0 The porosity of the pile core soil body;
m j =ρ j /n j is the viscous coupling coefficient of the layer soil skeleton and pore fluid of the j-th circle, b j =ρ fj g/k dj Is the Darcy law permeability coefficient of the soil body of the jth circle layer, m 0 =ρ 0 /n 0 Is the viscous coupling coefficient of the soil skeleton and pore fluid in the pile core soil, b 0 =ρ f0 g/k d0 The permeability coefficient of the pile core soil body is Darcy's law, and g is the gravity acceleration;
λ j shear modulus of soil body, G, of saturated soil body of j circle layer j Is Lame constant, upsilon of a saturated soil body of a jth circle layer sj The poisson ratio of the saturated soil body of the jth circle layer is defined; k sj Is the volume compression modulus, K, of soil particles in the saturated soil body of the jth circle fj Is the volume compression modulus, K, of the fluid in the saturated soil body of the jth circle bj =λ j +(23)×G j The volume compression modulus of a soil framework in the j-th circle of saturated soil body; k dj =K sj [1+n j (K sj /K fj -1)];
λ 0 Shear modulus of soil body, G, of pile core soil 0 Lame constant, upsilon, of pile core soil s0 The Poisson's ratio of the pile core soil is taken as the ratio; k s0 Is the volume compression modulus, K, of soil particles in the pile core soil f0 Is the bulk compression modulus, K, of the fluid in the core soil b0 =λ 0 +(23)×G 0 The volume compression modulus of a soil framework in the pile core soil is shown; k d0 =K s0 [1+n 0 (K s0 /K f0 -1)];
α j =1-K bj /K sj ,Respectively representing the compressibility of soil particles and fluid in the saturated soil body of the j-th circle of layer;
α 0 =1-K b0 /K s0 ,respectively representing the compressibility of soil particles and fluid in the pile core soil;
u p horizontally shifting the pile body of the tubular pile;
E p is shear modulus, I, of the pipe pile p Is the inertia moment of the tubular pile, A p Is the cross-sectional area of the tubular pile, m p Is the mass per unit length of the tubular pile, N 1 The transverse acting force of the axial unit length of the soil around the pile on the pile body of the pipe pile during horizontal vibration is N 0 The transverse acting force of axial unit length pile core soil on a pile body of the pipe pile during horizontal vibration.
Preferably, in step S2, the boundary condition of the pile-soil system is a boundary condition of a pile top of the pipe pile
Boundary condition of pile bottom of tubular pile
u p | z=H =0
Pile-soil full contact of the soil around the pile and waterproof conditions of the pile-soil interface
Continuous condition between loop layers
Limited displacement condition of pile core soil center
Pile-soil full contact of pile core soil and waterproof condition of pile-soil interface
In the above formulae, the symbols mean
j is 1-n, the number sequence of the ring layers is 1, the ring layer adjacent to the tubular pile is numbered, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of a z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is a horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
h is the length of the tubular pile, r 1 The radius of the tubular pile;
u p horizontally shifting the pile body of the tubular pile;
p (t) pile top excitation;
u rj is the radial displacement of the soil skeleton in the saturated soil body of the jth circle layer u θj Is the circumferential displacement, w, of the soil framework in the j-th circle of saturated soil body rj Is the radial displacement of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework, w θj The circumferential displacement of the fluid in the saturated soil body of the jth circle layer relative to the soil framework is obtained; u. of r0 Is the radial displacement of the soil skeleton in the pile core soil, u θ0 Is the circumferential direction of a pile core soil-in-soil frameworkDisplacement, w r0 Is the radial displacement of the fluid in the pile core soil relative to the soil skeleton, w θ0 The circumferential displacement of the fluid in the pile core soil relative to the soil framework is obtained;
σ rj is the normal stress on the interface of the j circle saturated soil body and the j +1 circle saturated soil body θj The tangential shear stress on the interface of the j-th circle of saturated soil and the j + 1-th circle of saturated soil is obtained.
Preferably, in the step S3, solving the motion equation of the saturated soil body and the pile core soil of each circle layer and the basic equation of the horizontal vibration of the pile body under the plane strain condition includes the following steps
S31: respectively introducing potential functions to soil skeleton and fluid in the saturated soil body of the jth circle layerψ sj ,ψ fj
S32: potential functionψ sj ,ψ fj Introducing a motion equation of a j-th circle saturated soil body under the condition of plane strain to perform Laplace transformation to obtain
ρ fj s 2 Ψ sj +m j s 2 Ψ fj +b j sΨ fj =0
S33: solving the potential function to obtain
Φ sj =[A j1 K 1 (β j1 r)+B j1 I 1 (β j1 r)+A j2 K 1 (β j2 r)+B j2 I 1 (β j2 r)]cosθ
Φ fj =[C j1 K 1 (β j1 r)+D j1 I 1 (β j1 r)+C j2 K 1 (β j2 r)+D j2 I 1 (β j2 r)]cosθ
Ψ sj =[A j3 K 1 (β j3 r)+B j3 I 1 (β j3 r)]sinθ
Ψ fj =[C j3 K 1 (β j3 r)+D j3 I 1 (β j3 r)]sinθ
S34: bringing back the potential function to obtain each displacement and stress expression containing undetermined coefficient
U rj ={A j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+A j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+A j3 K 1 (β j3 r)/r+B j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+B j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+B j3 I 1 (β j3 r)/r}cosθU θj ={-A j1 K 1 (β j1 r)/r-A j2 K 1 (β j2 r)/r-A j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-B j1 I 1 (β j1 r)-B j2 I 1 (β j2 r)/r-B j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
W rj ={C j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+C j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+C j3 K 1 (β j3 r)/r+D j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+D j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+D j3 I 1 (β j3 r)/r}cosθW θj ={-C j1 K 1 (β j1 r)/r-C j2 K 1 (β j2 r)/r-C j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-D j1 I 1 (β j1 r)-D j2 I 1 (β j2 r)/r-D j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
τ rθj =A j1 G j {-2[K 1 (β j1 r)]'/r+2K 1 (β j1 r)/r 2 }sinθ+A j2 G j {-2[K 1 (β j2 r)]'/r+2K 1 (β j2 r)/r 2 }sinθ+A j3 G j {[K 1 (β j3 r)]'/r-2K 1 (β j3 r)/r 2 -[K 1 (β j3 r)]”}sinθ+B j1 G j {-2[I 1 (β j1 r)]'/r+2I 1 (β j1 r)/r 2 }sinθ+B j2 G j {-2[I 1 (β j2 r)]'/r+2I 1 (β j2 r)/r 2 }sinθ+B j3 G j {[I 1 (β j3 r)]'/r-2I 1 (β j3 r)/r 2 -[I 1 (β j3 r)]”}sinθ
S35: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 ;
S36: the transverse acting force of the soil around the pile on the pile body is
S38: potential functionψ s0 ,ψ f0 Introducing the motion equation of the pile core soil under the condition of plane strain to perform Laplace transformation to obtain
ρ f0 s 2 Ψ s0 +m 0 s 2 Ψ f0 +b 0 sΨ f0 =0
S39: solving the potential function to obtain
Φ s0 =[B 01 I 1 (β 01 r)+B 02 I 1 (β 02 r)]cosθ
Φ f0 =[B 03 I 1 (β 01 r)+B 04 I 1 (β 02 r)]cosθ
Ψ s0 =B 05 I 1 (β 03 r)sinθ
Ψ f0 =B 06 I 1 (β 03 r)sinθ
S310: bringing back the potential function to obtain each displacement expression containing undetermined coefficients
U r0 ={B 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 I 1 (β 03 r)/r}cosθ
W r0 ={B 01 γ 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 γ 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 γ 03 I 1 (β 03 r)/r}cosθ
U θ0 ={-B 01 I 1 (β 01 r)-B 02 I 1 (β 02 r)/r-B 05 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
W θ0 ={-B 01 γ 01 I 1 (β 01 r)-B 02 γ 02 I 1 (β 02 r)/r-B 05 γ 03 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
S311: substituting the expression of the last step into boundary conditions, and solving to obtain undetermined coefficients
B 01 =(X 3 X 5 +X 5 X 9 -X 2 X 6 -X 6 X 8 )/κ
B 02 =(X 1 X 6 +X 6 X 7 -X 3 X 4 -X 4 X 9 )/κ;
B 03 =(X 2 X 4 +X 4 X 8 -X 1 X 5 -X 5 X 7 )/κ
S312: the transverse acting force of the pile core soil on the pile body is
S313: laplace transformation is carried out on the basic equation of horizontal vibration of the pile body
And solving to obtain
U p (z)=Y 1 cos(ηz)+Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)
Θ p (z)=η[-Y 1 sin(ηz)+Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
M p (z)=-E p I p η 2 [-Y 1 cos(ηz)-Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)]
Q p (z)=-E p I p η 3 [Y 1 sin(ηz)-Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
S314: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient
S315: calculating the horizontal dynamic impedance of the tubular pile
K QU =Q p (0)/U p (0)
Can also be expressed in dimensionless form as its real and imaginary parts
In the above expression, each symbol means
s is i omega, wherein s is Laplace transform, i is an imaginary number unit, and omega is the excitation load frequency;
j is 1-n, the number sequence of the ring layers is 1, the ring layer adjacent to the tubular pile is numbered, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of the z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is the horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
and psi sj Is the radial displacement u of the soil skeleton in the saturated soil body of the jth circle layer rj And the circumferential displacement u θj Is determined by the potential function of (a) a,ψ fj the radial displacement w of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework rj And circumferential displacement w θj A potential function of (d);
and psi s0 For radial displacement u of soil skeleton in pile core soil r0 And the circumferential displacement u θ0 Is determined by the potential function of (a) a,ψ f0 for radial displacement w of fluid in pile core soil relative to soil skeleton r0 And circumferential displacement w θ0 A potential function of (a);
Φ sj is a potential functionOf the laplace transform, Ψ sj Is a potential function psi sj Laplace transform of phi fj Is a potential functionOf the laplace transform, Ψ fj Is a potential function psi fj (ii) a laplace transform of; phi (phi) of s0 Is a potential functionOf the laplace transform, Ψ s0 Is a potential function psi s0 Laplace transform of phi f0 Is a potential functionOf the laplace transform, Ψ f0 Is a potential function psi f0 (ii) a laplace transform of;
ρ j =(1-n j )ρ sj +n j ρ fj for the saturated soil density of the jth circle layer, where p fj The density and rho of the fluid in the saturated soil body of the jth circle layer sj The density of soil particles in the saturated soil body of the jth circle layer, n j The porosity of the saturated soil body of the jth circle layer;
ρ 0 =(1-n 0 )ρ s0 +n 0 ρ f0 is the soil mass density of the pile core soil, where p f0 Density, rho, of fluid in the pile core soil body s0 Is the density of soil particles in the pile core soil body, n 0 The porosity of the pile core soil body;
m j =ρ j /n j is the viscous coupling coefficient of the layer soil skeleton and pore fluid of the j-th circle, b j =ρ fj g/k dj Is the Darcy law permeability coefficient of the soil body of the jth circle layer, m 0 =ρ 0 /n 0 Is the viscous coupling coefficient of soil skeleton and pore fluid in the pile core soil, b 0 =ρ f0 g/k d0 The permeability coefficient of the pile core soil body is Darcy's law, and g is the gravity acceleration;
λ j shear modulus of soil body, G, of saturated soil body of j circle layer j Is Lame constant, upsilon of a saturated soil body of a jth circle layer sj The Poisson ratio of the saturated soil body of the jth circle layer is obtained; k sj Is the volume compression modulus, K, of soil particles in the saturated soil body of the jth circle fj Is the volume compression modulus, K, of the fluid in the saturated soil body of the jth circle bj =λ j +(2/3)×G j The volume compression modulus of the soil framework in the j-th circle of saturated soil body is obtained; k is dj =K sj [1+n j (K sj /K fj -1)];
λ 0 Shear modulus of soil body, G, of pile core soil 0 Lame constant, upsilon, of pile core soil s0 The Poisson's ratio of the pile core soil is; k s0 For volume pressure of soil particles in pile core soilModulus of contraction, K f0 Is the bulk compression modulus, K, of the fluid in the core soil b0 =λ 0 +(2/3)×G 0 The volume compression modulus of the soil framework in the pile core soil is obtained; k d0 =K s0 [1+n 0 (K s0 /K f0 -1)];
α j =1-K bj /K sj ,Respectively representing the constants of compressibility of soil particles and fluid in the saturated soil body of the j-th circle of layer; alpha is alpha 0 =1-K b0 /K s0 ,Respectively representing the compressibility of soil particles and fluid in the pile core soil;
the first derivative of the expression in parentheses on r is shown;the expression in parentheses takes the second derivative of r;
η 4 =(m p s 2 +f 1 +f 0 )/E p I p is also a shorthand notation in the calculation process;
A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 is a symbol to be determined, and the following relationship exists
Y 1 ,Y 2 ,Y 3 ,Y 4 Is also a pending symbol;
X 1 =β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ,X 2 =β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ,X 3 =-I 1 (β 03 r 0 )/r 0 ,X 4 =γ 01 [β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ],X 5 =γ 02 [β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ],X 6 =γ 03 I 1 (β 03 r 0 )/r 0 ,X 7 =-I 1 (β 01 r 0 )/r 0 ,X 8 =-I 1 (β 02 r 0 )/r 0 ,X 9 =-[β 03 I 0 (β 03 r 0 )-I 1 (β 03 r 0 )/r 0 ],κ=X 1 X 5 X 9 +X 3 X 4 X 8 +X 2 X 6 X 7 -X 1 X 5 X 9 -X 1 X 6 X 8 -X 2 X 4 X 9 is also a shorthand notation in the calculation process;
a 5 =η[a 3 cos(ηH)-a 1 sin(ηH)],a 6 =-η[a 2 sin(ηH)+a 4 cos(ηH)]and a 7 =η[sin(ηH)cosh(ηH)+cos(ηH)sinh(ηH)]And is also a shorthand notation in the calculation process.
Preferably, in the step S1, the method for determining the shear modulus of the soil body of the jth circle is to
Wherein G (r) is the shear modulus of the soil at the position where the distance between the jth circle of soil and the center of the pile-soil interface is r
Wherein f (r) is a function of the change in shear modulus of the earth
Wherein GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile, and GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile>1 is soil hardening GR<1 is softening of soil, GR is 1 is uniform soil, q is positive index, r is 1 The radius of the pipe pile is b, and the radius of the soil body in the radial heterogeneous region is b.
According to the technical scheme, the horizontal vibration of the pipe pile is analyzed by adopting the radial heterogeneous saturated soil model based on the plane strain model, the adopted plane strain hypothesis can simply process the relatively complex actual engineering situation, the concept is clear, and the theoretical performance is strong; meanwhile, the Biot porous medium model considers the coupling effect between solid and liquid phases and is closer to the actual working condition compared with a single-phase medium. The radial heterogeneous performance considers the construction disturbance effect of the soil body around the pile and the influence of the pile core soil body on the horizontal vibration of the pipe pile, and can provide theoretical guidance and reference for the research of the more complex saturated soil-pile dynamic interaction problem.
Drawings
FIG. 1 is a flow chart of the method of the present invention;
FIG. 2 is a model schematic of the present invention.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
In the following detailed description of the embodiments of the present invention, in order to clearly illustrate the structure of the present invention and to facilitate explanation, it should be understood that the structure shown in the drawings is not drawn to general scale and is partially enlarged, modified or simplified, so that the present invention is not limited thereto.
In the following detailed description of the present invention, reference is made to FIG. 1, which is a flow chart of the method of the present invention. As shown in the figure.
The horizontal vibration analysis method for the radial heterogeneous saturated soil-in-pipe pile is characterized by comprising the following steps
The following assumptions are introduced, and a vibration model of the radial heterogeneous saturated soil pipe-in-pipe pile under horizontal excitation under the plane strain condition is established:
(1) assuming that the tubular pile is a linear elastic homogeneous uniform-section circular Bernoulli-Euler beam model, neglecting the shear deformation of a pile body, and adopting a fixed support at the pile end;
(2) the soil around the pile is divided into an inner area and an outer area, the inner area is divided into n circle layers, and the soil of each circle layer and the pile core soil are homogeneous and isotropic two-phase saturated elastic media;
(3) the pile-soil system vibrates in small deformation, the pile-soil interface is in complete contact without separation and slippage, the pile-soil interface is impervious to water, and the two sides of the soil interface of each ring layer are continuously displaced and have balanced stress;
(4) when the pile foundation horizontally vibrates, the soil body around the pile and the pile core soil have no vertical deformation.
The method for determining the shear modulus of the soil body of the jth circle layer comprises the following steps
Wherein G (r) is the shear modulus of the soil at the position where the distance between the jth circle of soil and the center of the pile-soil interface is r
Wherein f (r) is a function of the change in shear modulus of the earth
Wherein GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile, and GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile>1 is hardening of soil, GR<1 is softening of soil, GR is 1 is uniform soil, q is positive index, r is 1 The radius of the pipe pile is b, and the radius of the soil body in the radial heterogeneous region is b.
S2: establishing a motion equation of saturated soil bodies of all circle layers, a motion equation of pile core soil and a pile body horizontal vibration basic equation under a plane strain condition based on a Biot two-phase medium fluctuation theory; and establishes pile-soil system boundary conditions based on the assumptions in step S1.
The equation of motion of the saturated soil body of each circle layer under the condition of plane strain is
The equation of motion of the pile core soil is
The basic equation of horizontal vibration of the pile body is
The boundary condition of the pile-soil system is the boundary condition of the pile top of the pipe pile
Boundary condition of pile bottom of tubular pile
u p | z=H =0
Pile-soil full contact of the soil around the pile and waterproof conditions of the pile-soil interface
Continuous condition between loop layers
Limited displacement condition of pile core soil center
Pile-soil full contact of pile core soil and waterproof condition of pile-soil interface
S3: using laplace transform to solve the motion equation of the saturated soil body of each circle layer and the motion equation of the pile core soil under the plane strain condition established in the step S2 to obtain the horizontal dynamic impedance of the tubular pile so as to analyze the horizontal vibration of the tubular pile in the radially inhomogeneous saturated soil. Comprises the following specific steps
S31: respectively introducing potential functions to soil skeleton and fluid in the saturated soil body of the jth circle layerψ sj ,ψ fj
S32: potential functionψ sj ,ψ fj Introducing the motion equation of the saturated soil body of the j-th circle layer under the plane strain condition, and performing Laplace transformation to obtain
ρ fj s 2 Ψ sj +m j s 2 Ψ fj +b j sΨ fj =0
S33: solving the potential function to obtain
Φ sj =[A j1 K 1 (β j1 r)+B j1 I 1 (β j1 r)+A j2 K 1 (β j2 r)+B j2 I 1 (β j2 r)]cosθ
Φ fj =[C j1 K 1 (β j1 r)+D j1 I 1 (β j1 r)+C j2 K 1 (β j2 r)+D j2 I 1 (β j2 r)]cosθ
Ψ sj =[A j3 K 1 (β j3 r)+B j3 I 1 (β j3 r)]sinθ
Ψ fj =[C j3 K 1 (β j3 r)+D j3 I 1 (β j3 r)]sinθ
S34: bringing back the potential function to obtain each displacement and stress expression containing undetermined coefficient
U rj ={A j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+A j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+A j3 K 1 (β j3 r)/r+B j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+B j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+B j3 I 1 (β j3 r)/r}cosθ
U θj ={-A j1 K 1 (β j1 r)/r-A j2 K 1 (β j2 r)/r-A j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-B j1 I 1 (β j1 r)-B j2 I 1 (β j2 r)/r-B j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
W rj ={C j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+C j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+C j3 K 1 (β j3 r)/r+D j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+D j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+D j3 I 1 (β j3 r)/r}cosθW θj ={-C j1 K 1 (β j1 r)/r-C j2 K 1 (β j2 r)/r-C j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-D j1 I 1 (β j1 r)-D j2 I 1 (β j2 r)/r-D j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
τ rθj =A j1 G j {-2[K 1 (β j1 r)]'/r+2K 1 (β j1 r)/r 2 }sinθ+A j2 G j {-2[K 1 (β j2 r)]'/r+2K 1 (β j2 r)/r 2 }sinθ+A j3 G j {[K 1 (β j3 r)]'/r-2K 1 (β j3 r)/r 2 -[K 1 (β j3 r)]”}sinθ+B j1 G j {-2[I 1 (β j1 r)]'/r+2I 1 (β j1 r)/r 2 }sinθ+B j2 G j {-2[I 1 (β j2 r)]'/r+2I 1 (β j2 r)/r 2 }sinθ+B j3 G j {[I 1 (β j3 r)]'/r-2I 1 (β j3 r)/r 2 -[I 1 (β j3 r)]”}sinθ
S35: substituting the expression of the last step into the boundary condition, and solving to obtain undetermined coefficient A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 ;
S36: the transverse acting force of the soil around the pile on the pile body is
S38: potential functionψ s0 ,ψ f0 Introducing the motion equation of the pile core soil under the condition of plane strain to perform Laplace transformation to obtain
ρ f0 s 2 Ψ s0 +m 0 s 2 Ψ f0 +b 0 sΨ f0 =0
S39: solving the potential function to obtain
Φ s0 =[B 01 I 1 (β 01 r)+B 02 I 1 (β 02 r)]cosθ
Φ f0 =[B 03 I 1 (β 01 r)+B 04 I 1 (β 02 r)]cosθ
Ψ s0 =B 05 I 1 (β 03 r)sinθ
Ψ f0 =B 06 I 1 (β 03 r)sinθ
S310: bringing back the potential function to obtain each displacement and stress expression containing undetermined coefficient
U r0 ={B 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 I 1 (β 03 r)/r}cosθ
W r0 ={B 01 γ 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 γ 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 γ 03 I 1 (β 03 r)/r}cosθ
U θ0 ={-B 01 I 1 (β 01 r)-B 02 I 1 (β 02 r)/r-B 05 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
W θ0 ={-B 01 γ 01 I 1 (β 01 r)-B 02 γ 02 I 1 (β 02 r)/r-B 05 γ 03 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
S311: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient
B 01 =(X 3 X 5 +X 5 X 9 -X 2 X 6 -X 6 X 8 )/κ
B 02 =(X 1 X 6 +X 6 X 7 -X 3 X 4 -X 4 X 9 )/κ;
B 03 =(X 2 X 4 +X 4 X 8 -X 1 X 5 -X 5 X 7 )/κ
S312: the transverse acting force of the pile core soil on the pile body is
S313: laplace transformation is carried out on the basic equation of horizontal vibration of the pile body
And solving to obtain
U p (z)=Y 1 cos(ηz)+Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)
Θ p (z)=η[-Y 1 sin(ηz)+Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
M p (z)=-E p I p η 2 [-Y 1 cos(ηz)-Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)]
Q p (z)=-E p I p η 3 [Y 1 sin(ηz)-Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
S314: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient
S315: calculating the horizontal dynamic impedance of the tubular pile
K QU =Q p (0)/U p (0)
Can also be expressed in a dimensionless form of its real and imaginary parts
In the above formulae, the symbols have the following meanings:
j is 1-n and is the number sequence of the ring layers, the ring layer number adjacent to the tubular pile is 1, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of the z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is the horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
u rj is the radial displacement of the soil skeleton in the saturated soil body of the jth circle layer u θj Is the circumferential displacement, w, of the soil framework in the j-th circle of saturated soil body rj Is the jth turnRadial displacement, w, of fluid in a layer saturated soil body relative to a soil skeleton θj The circumferential displacement of the fluid in the saturated soil body of the jth circle layer relative to the soil framework is obtained;
u r0 is the radial displacement of the soil skeleton in the pile core soil, u θ0 Is the circumferential displacement, w, of the soil skeleton in the pile core soil r0 Is the radial displacement of the fluid in the pile core soil relative to the soil skeleton, w θ0 The circumferential displacement of the fluid in the pile core soil relative to the soil framework is obtained; sigma rj Is the normal stress on the interface of the j circle saturated soil body and the j +1 circle saturated soil body θj The tangential shear stress on the interface of the j circle saturated soil body and the j +1 circle saturated soil body is measured;
ρ j =(1-n j )ρ sj +n j ρ fj is the density of the saturated soil body of the jth circle layer, wherein rho fj The density, rho, of the fluid in the saturated soil body of the jth circle layer sj The density of soil particles in the saturated soil body of the jth circle layer, n j The porosity of the saturated soil body of the jth circle layer;
ρ 0 =(1-n 0 )ρ s0 +n 0 ρ f0 is the body density of the pile core soil, where ρ f0 Density, rho, of fluid in the pile core soil body s0 Is the density of soil particles in the pile core soil body, n 0 The porosity of the pile core soil body;
m j =ρ j /n j is the viscous coupling coefficient of the layer soil skeleton and pore fluid of the j-th circle, b j =ρ fj g/k dj Is the Darcy law permeability coefficient of the soil body of the jth circle layer, m 0 =ρ 0 /n 0 Is the viscous coupling coefficient of soil skeleton and pore fluid in the pile core soil, b 0 =ρ f0 g/k d0 The permeability coefficient of the pile core soil body is Darcy's law, and g is the gravity acceleration;
λ j shear modulus of soil body, G, of saturated soil body of jth circle layer j Is Lame constant, upsilon of a saturated soil body of a jth circle layer sj The Poisson ratio of the saturated soil body of the jth circle layer is obtained; k is sj Is the volume compression modulus, K, of soil particles in the saturated soil body of the jth circle fj Is the volume of fluid in the saturated soil body of the jth circle layerModulus of compression, K bj =λ j +(23)×G j The volume compression modulus of the soil framework in the j-th circle of saturated soil body is obtained; k dj =K sj [1+n j (K sj /K fj -1)];
λ 0 Shear modulus of soil body, G, of pile core soil 0 Lame constant, upsilon, of pile core soil s0 The Poisson's ratio of the pile core soil is; k is s0 Is the volume compression modulus, K, of soil particles in the pile core soil f0 Is the bulk compression modulus, K, of the fluid in the core soil b0 =λ 0 +(2/3)×G 0 The volume compression modulus of a soil framework in the pile core soil is shown; k is d0 =K s0 [1+n 0 (K s0 /K f0 -1)];
α j =1-K bj /K sj ,Respectively representing the compressibility of soil particles and fluid in the saturated soil body of the j-th circle of layer;
α 0 =1-K b0 /K s0 ,respectively representing the compressibility of soil particles and fluid in the pile core soil;
u p horizontally shifting the pile body of the tubular pile; h is the length of the tubular pile, r 1 Is the radius of the tubular pile;
E p is shear modulus, I, of the pipe pile p Is the inertia moment of the tubular pile, A p Is the cross-sectional area of the tubular pile, m p Is the mass per unit length of the tubular pile, N 1 The transverse acting force of the soil around the axial unit length on the pile body of the pipe pile during horizontal vibration is adopted; n is a radical of 0 The transverse acting force of axial unit length of pile core soil on a pile body of the pipe pile is generated during horizontal vibration;
s-i ω, where s is laplace transform, i is an imaginary unit, and ω is the excitation load frequency;
and psi sj Is the radial displacement u of the soil framework in the saturated soil body of the jth circle layer rj And the circumferential displacement u θj Is determined by the potential function of (a) a,ψ fj the radial displacement w of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework rj And circumferential displacement w θj A potential function of (d);and psi s0 For radial displacement u of soil skeleton in pile core soil r0 And the circumferential displacement u θ0 Is determined by the potential function of (a) a,ψ f0 for radial displacement w of fluid in pile core soil relative to soil skeleton r0 And circumferential displacement w θ0 A potential function of (d);
Φ sj is a potential functionOf laplace transform, Ψ sj Is a potential function psi sj Laplace transform of phi fj Is a potential functionOf the laplace transform, Ψ fj Is a potential function psi fj (ii) a laplace transform of; phi s0 Is a potential functionOf the laplace transform, Ψ s0 Is a potential function psi s0 Laplace transform of phi f0 Is a potential functionOf laplace transform, Ψ f0 Is a potential function psi f0 (ii) a laplace transform of;
the first derivative of the expression in parentheses on r is shown;the expression in parentheses takes the second derivative of r;
η 4 =(m p s 2 +f 1 +f 0 )/E p I p is also a shorthand notation in the calculation process;
A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 is a symbol to be determined, and the following relationship exists
Y 1 ,Y 2 ,Y 3 ,Y 4 Is also a pending symbol;
X 1 =β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ,X 2 =β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ,X 3 =-I 1 (β 03 r 0 )/r 0 ,X 4 =γ 01 [β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ],X 5 =γ 02 [β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ],X 6 =γ 03 I 1 (β 03 r 0 )/r 0 ,X 7 =-I 1 (β 01 r 0 )/r 0 ,X 8 =-I 1 (β 02 r 0 )/r 0 ,X 9 =-[β 03 I 0 (β 03 r 0 )-I 1 (β 03 r 0 )/r 0 ],κ=X 1 X 5 X 9 +X 3 X 4 X 8 +X 2 X 6 X 7 -X 1 X 5 X 9 -X 1 X 6 X 8 -X 2 X 4 X 9 is also a shorthand notation in the calculation process;
a 5 =η[a 3 cos(ηH)-a 1 sin(ηH)],a 6 =-η[a 2 sin(ηH)+a 4 cos(ηH)]and a 7 =η[sin(ηH)cosh(ηH)+cos(ηH)sinh(ηH)]And is also a shorthand notation in the calculation process.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (5)
1. The horizontal vibration analysis method for the pipe pile in the radial heterogeneous saturated soil is characterized by comprising the following steps
S1: the following assumptions are introduced, and a vibration model of the radial heterogeneous saturated soil pipe-in-pipe pile under horizontal excitation under the plane strain condition is established:
(1) assuming that the tubular pile is a linear elastic homogeneous uniform-section circular Bernoulli-Euler beam model, neglecting the shear deformation of a pile body, and adopting a fixed support at the pile end;
(2) the soil body around the pile is divided into an inner area and an outer area, the inner area is divided into n circle layers, and the soil body of each circle layer and the pile core soil are homogeneous and isotropic two-phase saturated elastic media;
(3) the pile-soil system vibrates in small deformation, the pile-soil interface is in complete contact without separation and slippage, the pile-soil interface is impervious to water, and the two sides of the soil interface of each ring layer are continuously displaced and have balanced stress;
(4) when the pile foundation horizontally vibrates, the soil body around the pile and the pile core soil have no vertical deformation;
s2: establishing a motion equation of saturated soil bodies of all ring layers, a motion equation of pile core soil and a pile body horizontal vibration basic equation under a plane strain condition based on a Biot two-phase medium fluctuation theory;
establishing pile-soil system boundary conditions according to the assumption in the step S1;
s3: and (4) solving the motion equation of the saturated soil body of each circle layer and the motion equation of the pile core soil under the plane strain condition established in the step S2 by using Laplace transformation to obtain the horizontal dynamic impedance of the tubular pile so as to analyze the horizontal vibration of the tubular pile in the radially inhomogeneous saturated soil.
2. The analysis method according to claim 1, wherein in step S2, the equation of motion of the saturated soil mass in each circle under the planar strain condition is
The equation of motion of the pile core soil is
The basic equation of horizontal vibration of the pile body is
In the above formulae, the symbols have the following meanings:
j is 1-n and is the number sequence of the ring layers, the ring layer number adjacent to the tubular pile is 1, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of the z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is the horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
u rj is the radial displacement of the soil skeleton in the saturated soil body of the jth circle layer u θj Is the circumferential displacement, w, of the soil framework in the j-th circle of saturated soil body rj Is the radial displacement of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework, w θj The circumferential displacement of the fluid in the saturated soil body of the jth circle layer relative to the soil framework is obtained;
u r0 is the radial displacement of the soil skeleton in the pile core soil, u θ0 Is the circumferential displacement, w, of the soil skeleton in the pile core soil r0 Is the radial displacement of the fluid in the pile core soil relative to the soil skeleton, w θ0 The circumferential displacement of the fluid in the pile core soil relative to the soil framework is obtained;
ρ j =(1-n j )ρ sj +n j ρ fj is the density of the saturated soil body of the jth circle layer, wherein rho fj The density and rho of the fluid in the saturated soil body of the jth circle layer sj The density of soil particles in the saturated soil body of the jth circle layer, n j The porosity of the saturated soil body of the jth circle layer;
ρ 0 =(1-n 0 )ρ s0 +n 0 ρ f0 is the soil mass density of the pile core soil,where ρ is f0 Density, rho, of fluid in the pile core soil body s0 Is the density of soil particles in the pile core soil body, n 0 The porosity of the pile core soil body;
m j =ρ j /n j is the viscous coupling coefficient of the layer soil skeleton and pore fluid of the j-th circle, b j =ρ fj g/k dj Is the Darcy law permeability coefficient of the soil body of the jth circle layer, m 0 =ρ 0 /n 0 Is the viscous coupling coefficient of soil skeleton and pore fluid in the pile core soil, b 0 =ρ f0 g/k d0 The permeability coefficient of the pile core soil body is Darcy's law, and g is the gravity acceleration;
λ j shear modulus of soil body, G, of saturated soil body of jth circle layer j Is Lame constant, upsilon of a saturated soil body of a jth circle layer sj The Poisson ratio of the saturated soil body of the jth circle layer is obtained; k sj Is the volume compression modulus, K, of soil particles in the saturated soil body of the jth circle fj Is the volume compression modulus, K, of the fluid in the saturated soil body of the jth circle bj =λ j +(2/3)×G j The volume compression modulus of the soil framework in the j-th circle of saturated soil body is obtained; k is dj =K sj [1+n j (K sj /K fj -1)];
λ 0 Shear modulus of soil body, G, of pile core soil 0 Lame constant, upsilon, of pile core soil s0 The Poisson's ratio of the pile core soil is taken as the ratio; k s0 Is the volume compression modulus, K, of soil particles in the pile core soil f0 Is the bulk compression modulus, K, of the fluid in the core soil b0 =λ 0 +(2/3)×G 0 The volume compression modulus of a soil framework in the pile core soil is shown; k d0 =K s0 [1+n 0 (K s0 /K f0 -1)];
α j =1-K bj /K sj ,Respectively representing the compressibility of soil particles and fluid in the saturated soil body of the j-th circle of layer;
α 0 =1-K b0 /K s0 ,respectively representing the compressibility of soil particles and fluid in the pile core soil;
u p horizontally displacing the pile body of the pipe pile;
E p is shear modulus, I, of the pipe pile p Is the inertia moment of the tubular pile, A p Is the cross-sectional area of the tubular pile, m p Is the mass per unit length of the tubular pile, N 1 The transverse acting force of the soil around the axial unit length on the pile body of the pipe pile during horizontal vibration is N 0 The transverse acting force of axial unit length of pile core soil on a pile body of the pipe pile is generated during horizontal vibration.
3. The analysis method according to claim 2, wherein in step S2, the pile-soil system boundary condition is a pile top boundary condition of a pipe pile
Boundary condition of pile bottom of tubular pile
u p | z=H =0
Pile-soil full contact of the soil around the pile and waterproof conditions of the pile-soil interface
Continuous condition between loop layers
Limited displacement condition of pile core soil center
Pile-soil full contact of pile core soil and waterproof condition of pile-soil interface
In the above formulae, the symbols mean
j is 1-n and is the number sequence of the ring layers, the ring layer number adjacent to the tubular pile is 1, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of the z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is the horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
h is the length of the tubular pile, r 1 Is the radius of the tubular pile;
u p horizontally displacing the pile body of the pipe pile;
p (t) exciting the pile top;
u rj is the radial displacement of the soil skeleton in the saturated soil body of the jth circle layer u θj Is the circumferential displacement, w, of the soil framework in the j-th circle of saturated soil body rj Is the radial displacement of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework, w θj The circumferential displacement of the fluid in the j-th circle of saturated soil body relative to the soil framework is obtained; u. of r0 Is the radial displacement of the soil skeleton in the pile core soil, u θ0 Is the circumferential displacement, w, of the soil skeleton in the pile core soil r0 Is the radial displacement of the fluid in the pile core soil relative to the soil skeleton, w θ0 The circumferential displacement of the fluid in the pile core soil relative to the soil framework is obtained;
σ rj is the j circle layer saturated soil body and the j +Normal stress, tau, at the interface of 1 circle of saturated soil θj The tangential shear stress on the interface of the j circle saturated soil body and the j +1 circle saturated soil body is obtained.
4. The analysis method according to claim 3, wherein the step S3 of solving the motion equation of the saturated soil body and the pile core soil of each circle layer and the basic equation of the horizontal vibration of the pile body under the plane strain condition comprises the following steps
S31: respectively introducing potential functions to soil skeleton and fluid in the saturated soil body of the jth circle layerψ sj ,ψ fj
S32: potential functionψ sj ,ψ fj Introducing a motion equation of a j-th circle saturated soil body under the condition of plane strain to perform Laplace transformation to obtain
ρ fj s 2 Ψ sj +m j s 2 Ψ fj +b j sΨ fj =0
S33: solving the potential function to obtain
Φ sj =[A j1 K 1 (β j1 r)+B j1 I 1 (β j1 r)+A j2 K 1 (β j2 r)+B j2 I 1 (β j2 r)]cosθ
Φ fj =[C j1 K 1 (β j1 r)+D j1 I 1 (β j1 r)+C j2 K 1 (β j2 r)+D j2 I 1 (β j2 r)]cosθ
Ψ sj =[A j3 K 1 (β j3 r)+B j3 I 1 (β j3 r)]sinθ
Ψ fj =[C j3 K 1 (β j3 r)+D j3 I 1 (β j3 r)]sinθ
S34: bringing back the potential function to obtain each displacement and stress expression containing undetermined coefficient
U rj ={A j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+A j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+A j3 K 1 (β j3 r)/r+B j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+B j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+B j3 I 1 (β j3 r)/r}cosθ
U θj ={-A j1 K 1 (β j1 r)/r-A j2 K 1 (β j2 r)/r-A j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-B j1 I 1 (β j1 r)-B j2 I 1 (β j2 r)/r-B j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
W rj ={C j1 [-β j1 K 0 (β j1 r)-K 1 (β j1 r)/r]+C j2 [-β j2 K 0 (β j2 r)-K 1 (β j2 r)/r]+C j3 K 1 (β j3 r)/r+D j1 [β j1 I 0 (β j1 r)-I 1 (β j1 r)/r]+D j2 [-β j2 I 0 (β j2 r)-I 1 (β j2 r)/r]+D j3 I 1 (β j3 r)/r}cosθ
W θj ={-C j1 K 1 (β j1 r)/r-C j2 K 1 (β j2 r)/r-C j3 [-β j3 K 0 (β j3 r)-K 1 (β j3 r)/r]-D j1 I 1 (β j1 r)-D j2 I 1 (β j2 r)/r-D j3 [β j3 I 0 (β j3 r)-I 1 (β j3 r)/r]}sinθ
τ rθj =A j1 G j {-2[K 1 (β j1 r)]'/r+2K 1 (β j1 r)/r 2 }sinθ+A j2 G j {-2[K 1 (β j2 r)]'/r+2K 1 (β j2 r)/r 2 }sinθ+A j3 G j {[K 1 (β j3 r)]'/r-2K 1 (β j3 r)/r 2 -[K 1 (β j3 r)]”}sinθ+B j1 G j {-2[I 1 (β j1 r)]'/r+2I 1 (β j1 r)/r 2 }sinθ+B j2 G j {-2[I 1 (β j2 r)]'/r+2I 1 (β j2 r)/r 2 }sinθ+B j3 G j {[I 1 (β j3 r)]'/r-2I 1 (β j3 r)/r 2 -[I 1 (β j3 r)]”}sinθ
S35: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 ;
S36: the transverse acting force of the soil around the pile on the pile body is
S38: potential functionψ s0 ,ψ f0 Introducing the motion equation of the pile core soil under the condition of plane strain to perform Laplace transformation to obtain
ρ f0 s 2 Ψ s0 +m 0 s 2 Ψ f0 +b 0 sΨ f0 =0
S39: solving the potential function to obtain
Φ s0 =[B 01 I 1 (β 01 r)+B 02 I 1 (β 02 r)]cosθ
Φ f0 =[B 03 I 1 (β 01 r)+B 04 I 1 (β 02 r)]cosθ
Ψ s0 =B 05 I 1 (β 03 r)sinθ
Ψ f0 =B 06 I 1 (β 03 r)sinθ
S310: bringing back the potential function to obtain each displacement expression containing undetermined coefficients
U r0 ={B 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 I 1 (β 03 r)/r}cosθ
W r0 ={B 01 γ 01 [β 01 I 0 (β 01 r)-I 1 (β 01 r)/r]+B 02 γ 02 [β 02 I 0 (β 02 r)-I 1 (β 02 r)/r]+B 05 γ 03 I 1 (β 03 r)/r}cosθ
U θ0 ={-B 01 I 1 (β 01 r)-B 02 I 1 (β 02 r)/r-B 05 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
W θ0 ={-B 01 γ 01 I 1 (β 01 r)-B 02 γ 02 I 1 (β 02 r)/r-B 05 γ 03 [β 03 I 0 (β 03 r)-I 1 (β 03 r)/r]}sinθ
S311: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient
B 01 =(X 3 X 5 +X 5 X 9 -X 2 X 6 -X 6 X 8 )/κ
B 02 =(X 1 X 6 +X 6 X 7 -X 3 X 4 -X 4 X 9 )/κ;
B 03 =(X 2 X 4 +X 4 X 8 -X 1 X 5 -X 5 X 7 )/κ
S312: the transverse acting force of the pile core soil on the pile body is
S313: laplace transformation is carried out on the basic equation of horizontal vibration of the pile body
And solving to obtain
U p (z)=Y 1 cos(ηz)+Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)
Θ p (z)=η[-Y 1 sin(ηz)+Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
M p (z)=-E p I p η 2 [-Y 1 cos(ηz)-Y 2 sin(ηz)+Y 3 cosh(ηz)+Y 4 sinh(ηz)]
Q p (z)=-E p I p η 3 [Y 1 sin(ηz)-Y 2 cos(ηz)+Y 3 sinh(ηz)+Y 4 cosh(ηz)]
S314: substituting the expression of the previous step into the boundary condition, and solving to obtain the undetermined coefficient
S315: calculating the horizontal dynamic impedance of the tubular pile
K QU =Q p (0)/U p (0)
Can also be expressed in dimensionless form as its real and imaginary parts
In the above expression, each symbol means
s is i omega, wherein s is Laplace transform, i is an imaginary number unit, and omega is the excitation load frequency;
j is 1-n and is the number sequence of the ring layers, the ring layer number adjacent to the tubular pile is 1, and n is the total number of the ring layers;
r and theta are coordinates of a cylindrical coordinate system, wherein the zero point of the z axis of the cylindrical coordinate system is positioned at the center of the circle of the upper surface of the tubular pile, the positive direction of the z axis is vertically downward, the direction of the r axis is the horizontal direction, and the zero point is positioned at the center of the circle of the upper surface of the tubular pile;
and psi sj Is the radial displacement u of the soil skeleton in the saturated soil body of the jth circle layer rj And the circumferential displacement u θj Is determined by the potential function of (a) a,ψ fj the radial displacement w of the fluid in the saturated soil body of the j-th circle layer relative to the soil framework rj And circumferential displacement w θj A potential function of (d);
and psi s0 For radial displacement u of soil skeleton in pile core soil r0 And the circumferential displacement u θ0 Is determined by the potential function of (a) a,ψ f0 for radial displacement w of fluid in pile core soil relative to soil skeleton r0 And circumferential displacement w θ0 A potential function of (a);
Φ sj is a potential functionOf laplace transform, Ψ sj Is a potential function psi sj Laplace transform of phi fj Is a potential functionOf the laplace transform, Ψ fj Is a potential function psi fj (ii) a laplace transform of; phi (phi) of s0 Is a potential functionOf the laplace transform, Ψ s0 Is a potential function psi s0 Laplace transform of phi f0 Is a potential functionOf laplace transform, Ψ f0 Is a potential function psi f0 Laplace transform of (d);
ρ j =(1-n j )ρ sj +n j ρ fj is the density of the saturated soil body of the jth circle layer, wherein rho fj The density and rho of the fluid in the saturated soil body of the jth circle layer sj The density of soil particles in the saturated soil body of the jth circle layer, n j The porosity of the saturated soil body of the jth circle layer;
ρ 0 =(1-n 0 )ρ s0 +n 0 ρ f0 is the soil mass density of the pile core soil, where p f0 Density, rho, of fluid in the pile core soil body s0 Is the density of soil particles in the pile core soil body, n 0 The porosity of the pile core soil body;
m j =ρ j /n j is the viscous coupling coefficient of the layer soil skeleton and pore fluid of the j-th circle, b j =ρ fj g/k dj Is the Darcy law permeability coefficient of the soil body of the jth circle layer, m 0 =ρ 0 /n 0 Is the viscous coupling coefficient of soil skeleton and pore fluid in the pile core soil, b 0 =ρ f0 g/k d0 The permeability coefficient of the pile core soil body is Darcy's law, and g is the gravity acceleration;
λ j shear modulus of soil body, G, of saturated soil body of jth circle layer j Is Lame constant, upsilon of a saturated soil body of a jth circle layer sj The Poisson ratio of the saturated soil body of the jth circle layer is obtained; k sj Is the volume compression modulus, K, of soil particles in the saturated soil body of the jth circle fj Is the volume compression modulus, K, of the fluid in the saturated soil body of the jth circle bj =λ j +(2/3)×G j Saturate for j-th circle layerThe volume compression modulus of a soil framework in a soil body; k is dj =K sj [1+n j (K sj /K fj -1)];
λ 0 Shear modulus of soil body, G, of pile core soil 0 Lame constant, upsilon, of pile core soil s0 The Poisson's ratio of the pile core soil is taken as the ratio; k is s0 Is the volume compression modulus, K, of soil particles in the pile core soil f0 Is the bulk compression modulus, K, of the fluid in the core soil b0 =λ 0 +(2/3)×G 0 The volume compression modulus of a soil framework in the pile core soil is shown; k d0 =K s0 [1+n 0 (K s0 /K f0 -1)];
α j =1-K bj /K sj ,Respectively representing the compressibility of soil particles and fluid in the saturated soil body of the j-th circle of layer; alpha is alpha 0 =1-K b0 /K s0 ,Respectively representing the compressibility of soil particles and fluid in the pile core soil;
the first derivative of the expression in parentheses on r is shown;the expression in parentheses takes the second derivative of r;
η 4 =(m p s 2 +f 1 +f 0 )/E p I p is also a shorthand notation in the calculation process;
A j1 ,A j2 ,A j3 ,B j1 ,B j2 ,B j3 ,C j1 ,C j2 ,C j3 ,D j1 ,D j2 ,D j3 is a symbol to be determined, and the following relationship exists
Y 1 ,Y 2 ,Y 3 ,Y 4 Is also a pending symbol;
X 1 =β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ,X 2 =β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ,X 3 =-I 1 (β 03 r 0 )/r 0 ,X 4 =γ 01 [β 01 I 0 (β 01 r 0 )-I 1 (β 01 r 0 )/r 0 ],X 5 =γ 02 [β 02 I 0 (β 02 r 0 )-I 1 (β 02 r 0 )/r 0 ],X 6 =γ 03 I 1 (β 03 r 0 )/r 0 ,X 7 =-I 1 (β 01 r 0 )/r 0 ,X 8 =-I 1 (β 02 r 0 )/r 0 ,X 9 =-[β 03 I 0 (β 03 r 0 )-I 1 (β 03 r 0 )/r 0 ],κ=X 1 X 5 X 9 +X 3 X 4 X 8 +X 2 X 6 X 7 -X 1 X 5 X 9 -X 1 X 6 X 8 -X 2 X 4 X 9 is also a shorthand notation in the calculation process;
5. The method of claim 1, wherein in step S1, the method for determining the shear modulus of the j-th circle of soil is
Wherein G (r) is the shear modulus of the soil at the position where the distance between the jth circle of soil and the center of the pile-soil interface is r
Wherein f (r) is a function of the change in shear modulus of the earth
Wherein GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile, and GR is a parameter for describing the disturbance degree of the construction of the soil body around the pile>1 is soil hardening GR<1 is softening of soil, GR is 1 is uniform soil, q is positive index, r is 1 The radius of the pipe pile is b, and the radius of the soil body in the radial heterogeneous region is b.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910459458.6A CN110162908B (en) | 2019-05-29 | 2019-05-29 | Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910459458.6A CN110162908B (en) | 2019-05-29 | 2019-05-29 | Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110162908A CN110162908A (en) | 2019-08-23 |
CN110162908B true CN110162908B (en) | 2022-09-27 |
Family
ID=67630217
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201910459458.6A Active CN110162908B (en) | 2019-05-29 | 2019-05-29 | Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110162908B (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112733244B (en) * | 2020-02-14 | 2023-05-26 | 大连海事大学 | Horizontal vibration analysis method for wedge-shaped piles in bidirectional heterogeneous saturated soil |
CN111539050B (en) * | 2020-02-14 | 2022-09-06 | 大连海事大学 | Method for analyzing horizontal vibration of solid pile in bidirectional heterogeneous saturated soil |
CN112034137B (en) * | 2020-08-14 | 2022-09-23 | 长沙理工大学 | Method for determining contact stress and vertical dynamic flexibility of rigid circular plate on saturated soil layer |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014002977A1 (en) * | 2012-06-25 | 2014-01-03 | 国立大学法人名古屋大学 | Air-water-soil skeleton coupled calculation device, coupled calculation method, and coupled calculation program |
CN109214123A (en) * | 2018-10-18 | 2019-01-15 | 大连海事大学 | It is a kind of that a Longitudinal vibration analysis method is held based on saturation the floating of loosened soil stake model |
CN109344526A (en) * | 2018-10-18 | 2019-02-15 | 大连海事大学 | A kind of saturation laminated soil pile foundation extensional vibration research method based on loosened soil stake model |
CN109446637A (en) * | 2018-10-24 | 2019-03-08 | 大连海事大学 | It is a kind of that a Longitudinal vibration analysis method is held based on stratiform saturation the floating of loosened soil stake |
-
2019
- 2019-05-29 CN CN201910459458.6A patent/CN110162908B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2014002977A1 (en) * | 2012-06-25 | 2014-01-03 | 国立大学法人名古屋大学 | Air-water-soil skeleton coupled calculation device, coupled calculation method, and coupled calculation program |
CN109214123A (en) * | 2018-10-18 | 2019-01-15 | 大连海事大学 | It is a kind of that a Longitudinal vibration analysis method is held based on saturation the floating of loosened soil stake model |
CN109344526A (en) * | 2018-10-18 | 2019-02-15 | 大连海事大学 | A kind of saturation laminated soil pile foundation extensional vibration research method based on loosened soil stake model |
CN109446637A (en) * | 2018-10-24 | 2019-03-08 | 大连海事大学 | It is a kind of that a Longitudinal vibration analysis method is held based on stratiform saturation the floating of loosened soil stake |
Non-Patent Citations (2)
Title |
---|
基于多孔介质理论的径向非均质饱和土中管桩的扭转振动;闫启方等;《信阳师范学院学报(自然科学版)》;20180403(第02期);全文 * |
基于多孔介质理论的非均质饱和土中单桩的纵向振动;刘林超等;《河南大学学报(自然科学版)》;20150516(第03期);全文 * |
Also Published As
Publication number | Publication date |
---|---|
CN110162908A (en) | 2019-08-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN110147631B (en) | Method for analyzing horizontal vibration of solid pile in radial heterogeneous saturated soil | |
CN110162908B (en) | Horizontal vibration analysis method for radial heterogeneous saturated soil pipe pile | |
CN113777278B (en) | Disturbance response prediction method and system for injecting carbon dioxide into multi-scale rock mass | |
Sadrekarimi et al. | A new ring shear device to measure the large displacement shearing behavior of sands | |
CN105275024B (en) | Defective Big-Diameter Rock-Embedded Pile vertical bearing capacity detection and the method reinforced | |
CN109446637A (en) | It is a kind of that a Longitudinal vibration analysis method is held based on stratiform saturation the floating of loosened soil stake | |
CN110147630B (en) | Method for analyzing longitudinal vibration of radial heterogeneous soil-in-pipe pile under transverse inertia effect | |
CN110222400B (en) | Method for analyzing longitudinal vibration of bidirectional heterogeneous soil-in-pipe pile under transverse inertia effect | |
CN111539050B (en) | Method for analyzing horizontal vibration of solid pile in bidirectional heterogeneous saturated soil | |
Ebeido et al. | Large scale liquefaction-induced lateral spreading shake table testing at the university of california San Diego | |
Senapati et al. | Effect of frequency on cyclic response of marine clay saturated with various pore fluids | |
JP5541523B2 (en) | Simple calculation method and apparatus for hydraulic conductivity | |
Moss et al. | Large-scale liquefaction and postliquefaction shake table testing | |
Kurup | Calibration chamber studies of miniature piezocone penetration tests in cohesive soil specimens | |
Consoli et al. | Crosswise-loaded pile tests on residual soil site | |
Manandhar et al. | Evaluation of skin friction of tapered piles in sands based on Cavity Expansion Theory | |
Voyiadjis et al. | Preparation of large-size cohesive specimens for calibration chamber testing | |
CN112733244B (en) | Horizontal vibration analysis method for wedge-shaped piles in bidirectional heterogeneous saturated soil | |
Dash et al. | Experimental py curves for liquefied soils from centrifuge tests | |
Thorel et al. | Installation process of suction anchors in Gulf of Guinea clay: centrifuge modelling | |
Momeni et al. | Study of physical modelling for piles | |
CN113960170A (en) | Method for determining motion response of tubular pile in saturated soil under action of earthquake P wave | |
CN111723512A (en) | Determination method of axial symmetry dynamic response of pile foundation considering radial deformation influence | |
CN109063334A (en) | A kind of fluid structure interaction mode construction method of LOW PERMEABILITY POROUS MEDIA material | |
CN115329449B (en) | Method for calculating optimal reserved interval of upper and lower sections of piles by reverse self-balancing pile testing method |
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 | ||
GR01 | Patent grant | ||
GR01 | Patent grant |