CN113641943B - Anchor rod reinforcement side slope analysis method considering stratum stress - Google Patents
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Abstract
The invention discloses an anchor rod reinforcement side slope analysis method considering stratum stress, which comprises the following steps: calculating the arc radius of the assumed sliding surface; establishing a plane coordinate system; calculating the slip moment of the side slope; calculating the anti-slip moment provided by the friction force and the cohesive force; calculating the whole anchoring moment; and calculating a safety coefficient and evaluating the slope stability. According to the invention, the anchor rod reinforcing side slope can be analyzed, the effective anchoring length of the anchor rod in the sliding state of the slope body is considered, the nonlinear distribution of the stress born by the anchor body in the triangular region of the slope body is considered, and the relatively real and accurate anchoring force is obtained, so that the number of the anchor rods required for reinforcing the side slope is determined, the number of the anchor rods is determined by the anchoring moment required to be lifted, and the number of the anchor rods is not required to be added when the safety coefficient is greater than 1, and the side slope is in a stable state. The invention brings great convenience and accuracy to the design and calculation of the anchor rod reinforced slope.
Description
Technical Field
The invention belongs to the field of rock-soil anchoring engineering, and particularly relates to an anchor rod reinforcement side slope analysis method considering stratum stress.
Background
In engineering applications, anchor rod reinforcement of unstable slopes has been a hot topic. The natural slope provides anti-slip moment to maintain slope stability by virtue of friction force and internal cohesion between soil particles, and when the anti-slip moment of the slope body is smaller than the slip moment due to external conditions, the slope body tends to slip damage.
On this basis, the implanted anchor rod can increase the anti-slip moment by increasing the anchoring force, thereby achieving the effect of reinforcing the side slope.
Disclosure of Invention
The invention provides an anchor rod reinforcement side slope analysis method considering stratum stress, aiming at solving the problems existing in the prior art.
The technical scheme of the invention is as follows: an anchor rod reinforcement side slope analysis method considering stratum stress comprises the following steps:
i. calculating the radius of the arc of the assumed sliding surface
Knowing the size of the toe θ, calculating the values of alpha and beta according to a fitting formula, wherein alpha is the included angle between an origin toe connecting line and a slope, and beta is the included angle between an origin toe connecting line and a horizontal line, and further deducing the length of the arc radius r through a triangular formula such as sine theorem;
ii. establishing a planar coordinate System
According to the rule that the sliding damage surface must pass through the slope toe and the radius of the circular arc, the position of the circle center can be found, the circle center is taken as an origin, the vertical direction is taken as the horizontal direction of the y axis, and a plane rectangular coordinate system is established;
calculating sliding moment of side slope
Dividing a side slope into a plurality of soil strips, wherein the product of the gravity of each soil strip and the distance from the center of mass of each soil strip to a round point is the sliding moment of the soil strip, and the sliding moment of the whole slope body is the sum of the sliding moment of each soil strip;
calculating the anti-slip moment provided by friction and cohesion
The natural slope reaches a self-stabilizing state by virtue of the friction force and the cohesive force among soil particles, the friction anti-slip moment is determined by the gravity of the soil strips, the sliding inclination angle of the soil strips and the internal friction angle of the soil, the cohesive force anti-slip moment is determined by the internal cohesive force of the soil, and the anti-slip moment provided by the friction force and the cohesive force is calculated; v. calculating the integral anchoring moment
When the slope cannot reach a self-stable state due to external reasons, anchor rods are implanted to carry out reinforcement treatment, the anchoring force of each anchor rod is influenced by the damage surface and stratum stress, the product of the anchor force and the moment arm is an anchoring moment, and the integral anchoring moment is obtained by accumulation and summation;
calculating safety coefficient and evaluating slope stability
And calculating to obtain a safety coefficient, if the safety coefficient is smaller than 1, the slope is in an unstable state, repeating the last two steps, adding the number of anchor rods, and improving the anti-slip moment until the safety coefficient meets the requirement.
Further, the calculation formulas of α, β and the arc radius r in the step i are as follows:
α＝1×10 -7 ×θ 5 -2×10 -5 ×θ 4 +0.0014θ 3 -0.037θ 2 +0.4346+23.238
β＝-4×10 -7 ×θ 5 +7×10 -5 ×θ 4 -0.0045θ 3 +0.1527θ 2 -2.5729θ+52.077
in the formula, h is the height of the side slope.
Further, the slip torque of the whole slope in step iii is calculated according to the following formula:
wherein m is the number of soil strips divided by the slope body.
Further, the anti-slip moment provided by the friction and cohesion is calculated in step iv, according to the following formula:
M adhesive tape ＝clr
In the formula, the gamma-slope soil weight and kN/m 3
S-area of soil strip, m 2
z-distance from mass center of soil strip to dot, m
Slide inclination angle of epsilon-soil body
c-internal cohesion of soil, kN/m 2
l-arc length of sliding body, m.
Further, in step v, the overall anchoring moment is calculated according to the following formula:
in the d-anchoring arm, m
Q-anchoring force, kN.
Further, in step ii, the trajectory equation of the sliding surface can be obtained according to the coordinate system and the sliding radius is
x 2 +y 2 ＝r 2
The slope shoulder abscissa can be deduced according to the slope angle theta and the slope height h, and the calculation formula is as follows:
furthermore, in the step v, the part of the anchor rod positioned in the sliding body loses the anchoring force, and the section which can truly provide the anchoring force is only the part inserted into the non-sliding soil body, and the actual anchoring section is calculated as x N To x M Is a part of the same.
Further, the formation stress of the anchoring body in the step v is attenuated by entering the slope triangular region, and the formation stress of the anchoring body is considered in a segmented manner for accurate calculation.
And (c) the stratum stress born by the anchoring body in the step (v) is an anchoring positive stress along the component vertical to the anchor rod, and the positive stress is put into a Lorenter formula to obtain the shearing force born by the anchor rod.
And (c) integrating the surface shearing force of the anchor rod in the step (v) to obtain the actual anchoring force of the anchor rod.
According to the invention, on one hand, the influence of the sliding surface on the anchoring area is considered, and on the other hand, the influence of the stratum stress change on the anchoring force is considered, when the sliding surface appears on the slope body, the anchoring capacity of the part of the anchor rod inserted into the sliding body is lost, and the effective anchoring length is only the part inserted into the undamaged soil body. The effective anchoring section enters the triangular region, and the stratum stress is changed due to reduction, so that the anchoring force of the part is treated in a segmented manner. The number of the anchor rods is determined by the anchoring moment to be lifted, and when the safety coefficient is greater than 1, the number of the anchor rods is not required to be increased, and the side slope is in a stable state.
The invention can analyze the anchor rod reinforced side slope, considers the effective anchoring length of the anchor rod in the sliding state of the slope body and considers the nonlinear distribution of the stress born by the anchor body entering the triangular region of the slope body to obtain a relatively real and accurate anchoring force, thereby determining the number of the anchor rods required for reinforcing the side slope.
Drawings
FIG. 1 is a flow chart of the method of the present invention;
FIG. 2 is a schematic diagram of the soil splitting of a side slope in the invention;
FIG. 3 is a schematic view of the non-entry triangle anchor of the present invention;
FIG. 4 is a schematic view of an entry triangle anchor according to the present invention;
fig. 5 is a schematic view of the anchoring of a plurality of anchor rods in the present invention.
Detailed Description
The present invention will be described in detail below with reference to the drawings and examples:
as shown in fig. 1 to 5, an anchor rod reinforcement slope analysis method taking into consideration stratum stress includes the following steps:
the method comprises the following steps:
i. calculating the radius of the arc of the assumed sliding surface
Knowing the size of the toe θ, calculating the values of alpha and beta according to a fitting formula, wherein alpha is the included angle between an origin toe connecting line and a slope, and beta is the included angle between an origin toe connecting line and a horizontal line, and further deducing the length of the arc radius r through a triangular formula such as sine theorem;
ii. establishing a planar coordinate System
According to the rule that the sliding damage surface must pass through the slope toe and the radius of the circular arc, the position of the circle center can be found, the circle center is taken as an origin, the vertical direction is taken as the horizontal direction of the y axis, and a plane rectangular coordinate system is established;
calculating sliding moment of side slope
Dividing a side slope into a plurality of soil strips, wherein the product of the gravity of each soil strip and the distance from the center of mass of each soil strip to a round point is the sliding moment of the soil strip, and the sliding moment of the whole slope body is the sum of the sliding moment of each soil strip;
calculating the anti-slip moment provided by friction and cohesion
The natural slope reaches a self-stabilizing state by virtue of the friction force and the cohesive force among soil particles, the friction anti-slip moment is determined by the gravity of the soil strips, the sliding inclination angle of the soil strips and the internal friction angle of the soil, the cohesive force anti-slip moment is determined by the internal cohesive force of the soil, and the anti-slip moment provided by the friction force and the cohesive force is calculated; v. calculating the integral anchoring moment
When the slope cannot reach a self-stable state due to external reasons, anchor rods are implanted to carry out reinforcement treatment, the anchoring force of each anchor rod is influenced by the damage surface and stratum stress, the product of the anchor force and the moment arm is an anchoring moment, and the integral anchoring moment is obtained by accumulation and summation;
calculating safety coefficient and evaluating slope stability
And calculating to obtain a safety coefficient, if the safety coefficient is smaller than 1, the slope is in an unstable state, repeating the last two steps, adding the number of anchor rods, and improving the anti-slip moment until the safety coefficient meets the requirement.
In the step i, the calculation formulas of alpha, beta and the arc radius r are as follows:
α＝1×10 -7 ×θ 5 -2×10 -5 ×θ 4 +0.0014θ 3 -0.037θ 2 +0.4346+23.238
β＝-4×10 -7 ×θ 5 +7×10 -5 ×θ 4 -0.0045θ 3 +0.1527θ 2 -2.5729θ+52.077
in the formula, h is the height of the side slope.
In step iii, the slip torque of the whole slope body is calculated according to the following formula:
wherein m is the number of soil strips divided by the slope body.
The anti-slip moment provided by the friction and cohesion is calculated in step iv, according to the following formula:
M adhesive tape ＝clr
In the formula, the gamma-slope soil weight and kN/m 3
S-area of soil strip, m 2
z-distance from mass center of soil strip to dot, m
Slide inclination angle of epsilon-soil body
c-internal cohesion of soil, kN/m 2
l-arc length of sliding body, m.
And (v) calculating the whole anchoring moment according to the following formula:
in the d-anchoring arm, m
Q-anchoring force, kN.
In step ii, the trajectory equation of the sliding surface can be obtained according to the coordinate system and the sliding radius as
x 2 +y 2 ＝r 2
The slope shoulder abscissa can be deduced according to the slope angle theta and the slope height h, and the calculation formula is as follows:
in the step v, the part of the anchor rod positioned in the sliding body loses the anchoring force, and the section which can truly provide the anchoring force is only the part inserted into the non-sliding soil body, and the actual anchoring section is calculated as x N To x M Is a part of the same.
In the step v, the stratum stress of the anchoring body is attenuated due to entering the slope triangular region, and the stratum stress of the anchoring body is considered in a segmented mode for accurate calculation.
And v, taking the stratum stress born by the anchoring body as anchoring positive stress along the component vertical to the anchor rod, and putting the positive stress into a Lorenter formula to obtain the shearing force born by the anchor rod.
And v, integrating the surface shearing force of the anchor rod to obtain the real anchoring force of the anchor rod.
Step vi, calculating a safety coefficient according to the following formula:
preferably, the actual anchoring segment is x N To x M The calculation process of the part of (2) is as follows:
setting the track equation of the anchor rod as a linear function for facilitating calculation
y＝kx+b
Selecting the incident position of the first anchor rod as the incident position according to the shoulder S 0 Where the incident angle is i, oneSolving the power of the equation:
is combined with the arc track equation
Solving to obtain the abscissa of the intersection point
Also known is an overall length of anchor rod of l 0 The abscissa of the rod end is
Thus, the actual anchoring section is obtained as x N To x M Is a part of the same.
Preferably, the anchoring body is subjected to the formation stress sectioning according to the following formula:
preferably, the shear force applied to the anchor rod is according to the following formula:
preferably, the real anchoring force of the anchor rod is obtained by integrating the surface shearing force of the anchor rod:
in the first case, when x M ≤x P When (1):
in the second case, when x M ＞x P When the actual anchoring section of the anchor rod enters the triangular area of the side slope, the anchoring force of the anchor rod is divided into Q 1 yτ Q and Q 2 yτ Two parts are considered.
Further, in calculating the anchoring arm, it can be reduced to the distance from the origin to the linear equation, i.e
Example 1
The natural homogeneous cohesive soil side slope is shown in figure 1.
The slope body generates a downward sliding damage trend under the action of gravity, and the slope body is assumed to slide along the arc surface AC, the radius of the sliding surface is r, the slope height is h, and the slope angle is theta.
The values of alpha and beta can be obtained empirically.
α＝1×10 -7 ×θ 5 -2×10 -5 ×θ 4 +0.0014θ 3 -0.037θ 2 +0.4346+23.238
β＝-4×10 -7 ×θ 5 +7×10 -5 ×θ 4 -0.0045θ 3 +0.1527θ 2 -2.5729θ+52.077
The method further comprises the following steps:
∠APO＝180°－β，∠OPC＝β+θ，∠POC＝180°－α－β－θ，∠OCK＝180°－α－θ。
determining the distance between the sliding surface radius, OP and OB:
in Δopc and Δaop:
wherein: l (L) OP -the distance between the point P and the origin, m;
l PC -ramp length, m;
l OC -distance between toe C and origin, m;
θ—slope angle, °.
The distance l between the sliding surface radii r and OP can be obtained according to the formula OP Distance l between OB OB Sine value of +.AOP:
l OB ＝rsin∠OAP
wherein: r—sliding surface radius, m;
h is the height of the side slope, m.
Taking the O point as the origin and the radius r as the circle, the track equation of the sliding surface can be obtained:
x 2 +y 2 ＝r 2
calculating the sliding moment of the slope body, dividing the slope body into a plurality of soil strips, wherein the product of the distance from the center of mass of each soil strip to the round point and the gravity of the soil strip is the sliding moment of the soil strip, and the integral sliding moment of the slope body is the sum of the sliding moments of the soil strips, and taking the slope into 5 soil strips as an example.
M Sliding device ＝M 1 +M 2 +M 3 +M 4 +M 5
Wherein:
X A ＝-rcos∠OAP
Y P ＝Y A ＝-rsin∠OAP
wherein: gamma soil body weight, kN/m 3 。
Wherein:
wherein:
wherein: x is x 0 -width of quadrilateral earth strip, m.
Wherein:
wherein:
X C ＝-r|cos(180°-θ-α)|
Y C ＝-r sin(180°-θ-α)
the natural anti-slip moment of the slope body is composed of two parts, one part is provided by friction force, and the other part is provided by internal cohesive force of soil. The anti-slip moment provided by the friction force is calculated, the normal stress of each soil strip acting on the sliding surface needs to be calculated, the product of the force and the internal friction angle of the soil is the friction force born by the soil, and the arm of the friction force is the radius of the sliding surface, so that the anti-slip moment provided by the friction force can be calculated.
Wherein:
epsilon-slip inclination angle of soil strip, °.
And calculating the anti-slip moment provided by the cohesive force of the soil, namely calculating the product of the cohesive force, the arc length of the sliding soil body and the arc radius.
M Adhesive tape ＝clr
M Anti-cancer agent ＝M Friction wheel +M Adhesive tape
The safety coefficient of the slope body is as follows:
if the safety coefficient is greater than 1, the slope body is in a stable state without reinforcement. If the weight of the anchor rod is smaller than 1, anchor rods are implanted into the slope body for reinforcement treatment. Assuming that the point Q is the incident point of the anchor rod, the linear distance PQ of the point from the slope shoulder P is s 0 Length of anchor rod l 0 The distance between the anchor rods is s 1 Radius r of anchor body 0 . The anchoring force of the bolt at the sliding body portion will fail, the actual anchoring force being provided by the portion in the undamaged soil body, i.e. the MN portion.
The coordinates of the incident point Q point are:
y Q ＝-s 0 sinθ-r sin∠OAP
the linear equation of the position of the first anchor rod is set as follows:
y＝kx+b＝tan i×x+b
substituting the Q point coordinates and the slope k=tani into a linear equation, the intercept b can be obtained:
wherein: s is(s) 0 -the linear distance m between the intersection point Q of the first anchor rod and the slope and the point P of the slope shoulder;
i-the angle between the anchor rod body and the horizontal line;
therefore, the linear equation of the position of the first anchor rod is:
and solving an arc track equation and a linear equation simultaneously:
the expression of the abscissa of the intersection point M of the slope sliding surface and the anchor rod can be obtained:
considering the influence of the reduction effect of the side slope on the stress at any position of the side slope soil, the dead weight stress expression at any position of the side slope soil can be obtained as follows:
the stress at each point of the actual anchoring section of the anchor rod is decomposed, so that the positive stress along the length direction of the anchor rod can be obtained:
the expression of the shear stress at each point of the actual anchoring section of the anchor rod can be obtained by the coulomb formula:
axial force Q of the anchor segment:
when x is M ≤x P When (1):
when x is M ＞x P When the anchoring rod body is partially entered into the triangular area of the side slope, the anchoring force of the anchoring rod is divided into Q 1 yτ Q and Q 2 yτ Two parts are considered:
wherein:
the nth anchor rod anchoring force expression:
wherein: when (when)x M ≤x P When (1):
when x is M ＞x P When the anchor rod body is partially entered into the triangular area of side slope, the stress around the anchor rod is divided into Q 1 yτ Q and Q 2 yτ Two parts are considered:
wherein:
s' 0 ＝s 0 +(n-1)s 1
the anchoring force arm of the anchor rod is the distance from the round point to the linear equation of the anchor rod, and the product of the anchoring force of the anchor rod and the anchoring force arm is the anchoring moment, so that the product becomes a part of the anti-slip moment. The anti-slip moment is enhanced by continuously increasing the number of the anchor rods until the requirement of the safety coefficient is met.
Wherein:
example two
The height h=10m of a certain side slope, the side slope rate is 1:1, and the physical and mechanical parameters are gamma=23 kN/m 3 Internal friction anglec=12 kPa, the anchor rod lengths are all 8m, the included angle i=30° between the anchor rod body and the horizontal line, and the straight line distance between the point Q and the point P is s 0 =2m, the straight line distances QE between the anchors are s 1 =1m, anchor radius r 0 =0.02m, square earth strip width x 0 ＝0.5m。
Solving the radius r of the sliding surface:
(ii) Angle OAP and straight line l OP 、l OB Solving:
l OB ＝rsin∠OAP＝17×0.376≈6.392m
(iii) calculation of a slip torque:
M sliding device ＝M 1 +M 2 +M 3 +M 4 +M 5
Calculation of friction-provided anti-slip moment = 35439.132 kn.m (iv)
(v) calculating the anti-slip moment provided by the cohesion
M Adhesive tape ＝clr＝4999.5kN·m
(vi) calculating a safety factor
The side slope is unstable and needs to be reinforced by anchor rods.
(vii) calculating the anchoring moment of the first Anchor
(viii) calculating the safety factor again
Since the safety factor is still less than 1, which means that the number of anchors still has to be increased, the following steps are repeated in (vii) (viii) cycles until the safety factor is greater than 1. The calculation steps of the 2 nd anchor rod, the 3 rd anchor rod and the 4 th anchor rod are not repeated, and the anchoring moments are 37.882 kN.m, 74.118 kN.m and 86.264 kN.m respectively.
When the 4 th anchor rod is implanted into the side slope, the safety coefficient is greater than 1, which indicates that the side slope reaches a safety state, and the reinforcement of the anchor rod effectively prevents the sliding of the slope body. If the reserved safety reserve is considered, a certain number of anchor rods can be implanted on the basis of slope stability so as to improve the safety coefficient.
The invention can analyze the anchor rod reinforced side slope, considers the effective anchoring length of the anchor rod in the sliding state of the slope body and considers the nonlinear distribution of the stress born by the anchor body entering the triangular region of the slope body to obtain a relatively real and accurate anchoring force, thereby determining the number of the anchor rods required for reinforcing the side slope.
Claims (10)
1. An anchor rod reinforcement side slope analysis method considering stratum stress is characterized in that: the method comprises the following steps:
the method comprises the following steps:
(i) Calculating the radius of the arc of the assumed sliding surface
Knowing the size of the toe θ, calculating the values of alpha and beta according to a fitting formula, wherein alpha is the included angle between an origin toe connecting line and a slope, and beta is the included angle between an origin toe connecting line and a horizontal line, and further deducing the length of the arc radius r through a triangular formula such as sine theorem;
(ii) Establishing a plane coordinate system
According to the rule that the sliding damage surface must pass through the slope toe and the radius of the circular arc, the position of the circle center can be found, the circle center is taken as an origin, the vertical direction is taken as the horizontal direction of the y axis, and a plane rectangular coordinate system is established;
(iii) Calculating sliding moment of side slope
Dividing a side slope into a plurality of soil strips, wherein the product of the gravity of each soil strip and the distance from the center of mass of each soil strip to a round point is the sliding moment of the soil strip, and the sliding moment of the whole slope body is the sum of the sliding moment of each soil strip;
(iv) Calculating anti-slip moment provided by friction and cohesion
The natural slope reaches a self-stabilizing state by virtue of the friction force and the cohesive force among soil particles, the friction anti-slip moment is determined by the gravity of the soil strips, the sliding inclination angle of the soil strips and the internal friction angle of the soil, the cohesive force anti-slip moment is determined by the internal cohesive force of the soil, and the anti-slip moment provided by the friction force and the cohesive force is calculated;
(v) Calculating the integral anchoring moment
When the slope cannot reach a self-stable state due to external reasons, anchor rods are implanted to carry out reinforcement treatment, the anchoring force of each anchor rod is influenced by the damage surface and stratum stress, the product of the anchor force and the moment arm is an anchoring moment, and the integral anchoring moment is obtained by accumulation and summation;
(vi) Calculating the safety coefficient and evaluating the slope stability
Calculating to obtain a safety coefficient, if the safety coefficient is smaller than 1, the slope is in an unstable state, repeating the last two steps, adding the number of anchor rods, and improving the anti-slip moment until the safety coefficient meets the requirement;
step vi, calculating a safety coefficient according to the following formula:
preferably, the actual anchoring segment is x N To x M The calculation process of the part of (2) is as follows:
setting the track equation of the anchor rod as a linear function for facilitating calculation
y＝kx+b
Selecting the incident position of the first anchor rod as the incident position according to the shoulder S 0 At the incidence angle i, then the first order equation is solved as:
is combined with the arc track equation
Solving to obtain the abscissa of the intersection point
Also known are anchor rod unitsLength of l 0 The abscissa of the rod end is
Thus, the actual anchoring section is obtained as x N To x M Is a part of the same.
2. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: the calculation formula of alpha, beta and the arc radius r in the step (i) is as follows:
α＝1×10 -7 ×θ 5 -2×10 -5 ×θ 4 +0.0014θ 3 -0.037θ 2 +0.4346+23.238
β＝-4×10 -7 ×θ 5 +7×10 -5 ×θ 4 -0.0045θ 3 +0.1527θ 2 -2.5729θ+52.077
in the formula, h is the height of the side slope.
3. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: in the step (iii), the slip torque of the whole slope body is calculated according to the following formula:
wherein m is the number of soil strips divided by the slope body.
4. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: calculating the anti-slip moment provided by the friction and cohesion in step (iv), according to the following formula:
M adhesive tape ＝clr
In the formula, the gamma-slope soil weight and kN/m 3
S-area of soil strip, m 2
z-distance from mass center of soil strip to dot, m
Slide inclination angle of epsilon-soil body
c-internal cohesion of soil, kN/m 2
l-arc length of sliding body, m.
5. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: calculating the whole anchoring moment in the step (v), wherein the whole anchoring moment is calculated according to the following formula:
in the d-anchoring arm, m
Q-anchoring force, kN.
6. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: in the step (ii), the trajectory equation of the sliding surface can be obtained according to the coordinate system and the sliding radius is
x 2 +y 2 ＝r 2
The slope shoulder abscissa can be deduced according to the slope angle theta and the slope height h, and the calculation formula is as follows:
7. the method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: in the step (v), the part of the anchor rod positioned in the sliding body loses the anchoring force, and the section which can truly provide the anchoring force is only the part inserted into the non-sliding soil body, and the actual anchoring section is calculated as x N To x M Is a part of the same.
8. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: the formation stress on the anchor in step (v) is attenuated by entering the slope triangle, and the formation stress on the anchor is considered in sections for accurate calculation.
9. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress as claimed in claim 1, wherein the method comprises the following steps of: and (v) taking the stratum stress born by the anchoring body as anchoring positive stress along the component vertical to the anchor rod, and putting the positive stress into a Lorenter formula to obtain the shearing force born by the anchor rod.
10. The method for analyzing the anchor rod reinforced side slope taking into consideration the stratum stress according to claim 9, wherein the method comprises the following steps of: and (v) integrating the surface shearing force of the anchor rod to obtain the actual anchoring force of the anchor rod.
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| CN110688747A (en) * | 2019-09-19 | 2020-01-14 | 昆明理工大学 | Rock slope anchoring calculation method based on safety and economy multi-objective optimization |
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