CN114357718A - Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter - Google Patents
Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter Download PDFInfo
- Publication number
- CN114357718A CN114357718A CN202111480644.1A CN202111480644A CN114357718A CN 114357718 A CN114357718 A CN 114357718A CN 202111480644 A CN202111480644 A CN 202111480644A CN 114357718 A CN114357718 A CN 114357718A
- Authority
- CN
- China
- Prior art keywords
- weakening
- coefficient
- value
- slope
- internal friction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000003313 weakening effect Effects 0.000 title claims abstract description 120
- 239000002689 soil Substances 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000013178 mathematical model Methods 0.000 claims abstract description 12
- 230000008859 change Effects 0.000 claims abstract description 10
- 238000004364 calculation method Methods 0.000 claims abstract description 7
- 231100000817 safety factor Toxicity 0.000 claims description 54
- 238000004458 analytical method Methods 0.000 claims description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 238000013461 design Methods 0.000 claims description 14
- 230000004044 response Effects 0.000 claims description 7
- 238000011156 evaluation Methods 0.000 abstract description 2
- 230000002265 prevention Effects 0.000 abstract description 2
- 230000006872 improvement Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 101150024075 Mapk1 gene Proteins 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010835 comparative analysis Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Images
Landscapes
- Pit Excavations, Shoring, Fill Or Stabilisation Of Slopes (AREA)
Abstract
The invention discloses a method for determining a maximum weakening coefficient of a bank slope rock-soil body strength parameter, which at least comprises the following steps: establishing a mathematical model; calculating the cohesive force value c after weakeningiAnd internal friction angle value
Inputting the data into a mathematical model, calculating the safety coefficient, taking the minimum value, repeating the calculation to obtain the minimum safety coefficient F corresponding to the weakening coefficientij(ii) a Changing the cohesive force weakening coefficient, repeating the steps, and drawing a slope minimum safety factor contour map; calculating the cohesive force value c after weakeningckAnd internal friction angle value
Calculating the probability of failure Pfk(ii) a And drawing a change curve between the weakening coefficient combination value and the failure probability, and taking the maximum weakening coefficient. The method determines the maximum weakening coefficient of the rock-soil body strength parameter of the bank side slope according to the given conditions, increases the safety consideration on the bank side slope, verifies the influence of the weakening coefficient of the rock-soil body strength parameter on the stability of the bank side slope, and can be widely applied to the technical field of stability evaluation and disaster prevention and control of the bank side slope.
Description
Technical Field
The invention relates to the technical field of stability evaluation and disaster prevention and control of bank slopes, in particular to a method for determining a maximum weakening coefficient of a rock-soil body strength parameter of a bank slope.
Background
In recent years, the problem of managing bank slopes has become a key problem in the construction and operation of water conservancy infrastructure, and statistical data in the past shows that the number of reservoir constructions is increasing year by year, and disasters caused by bank slope instability are also increasing year by year, so that great economic loss and casualties are caused. In the process of reservoir water level reduction, strength parameters (cohesive force and internal friction angle) of the slope rock-soil body are limited by a plurality of factors such as water content, particle size distribution, porosity ratio and the like, wherein the increase of the water content is beneficial to dislocation and sliding inside soil body particles, and the reduction and the weakening of the internal friction angle and the cohesive force are inevitably caused; in actual engineering of the bank side slope, the influence of the stability of the side slope is generally required to be considered for controlling the weakening coefficient of the rock-soil body strength parameter of the bank side slope, and when the weakening coefficient of the rock-soil body strength parameter of the side slope is smaller, the stability of the side slope is lower, and vice versa. The research on the influence factors of the stability of the bank and bank side slopes in the past mainly focuses on the variation of the water level of the bank, the existing method for controlling the weakening coefficient of the rock and soil mass strength parameters of the bank and bank side slopes by combining the slope stability degree is not comprehensive enough, and the determination of the maximum weakening coefficient of the rock and soil mass strength parameters of the bank and bank side slopes still faces challenges.
Disclosure of Invention
The invention aims to overcome the defects of the technology and provides a method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter.
In order to solve the technical problems, the technical scheme provided by the invention is a method for determining the maximum weakening coefficient of the strength parameter of the bank slope rock-soil mass, which at least comprises the following steps:
(1) establishing a mathematical model;
(2) calculating cohesive force weakening coefficient B1Value of cohesion after weakening of1And internal friction angle value
Will be provided with
Inputting a mathematical model, calculating and analyzing the corresponding safety factors of the time steps, taking the minimum value of the safety factors, repeating the calculation to obtain the minimum safety factor F corresponding to the weakening coefficientij；
(3) Changing the cohesive force weakening coefficient, repeating the step (2), and drawing a contour map of the minimum safety coefficient of the side slope;
(4) calculating a cohesive force value c after weakening according to a safety factor recommended by a hydraulic and hydro-power engineering slope design specification (SL386-2007) and a slope minimum safety factor contour mapckAnd internal friction angle value
Calculating the safety factors and failure probability P corresponding to the N samples under the analysis time step corresponding to the minimum safety factor of the side slopefk；
(5) And drawing a change curve between the weakening coefficient combination value and the failure probability, wherein the weakening coefficient combination value corresponding to the minimum failure probability is the maximum weakening coefficient.
As an improvement, in the mathematical model in the step (1), the reservoir water level descending speed is V, and X slope stability analysis time steps are set and recorded as A1，A2，A3，......AXAiming at cohesive force and internal friction in reservoir bank slope rock-soil body strength parametersThe design angle has K weakening coefficients which are respectively marked as B1，B2，B3，.......BKAnd Q1，Q2，……，QK；
Wherein, the V-descending speed is meter/day; x-the number of different time steps set in the slope seepage analysis; a. the1，A2，A3，......AX-each corresponding time step of X time steps of slope seepage analysis; b is1，B2，B3，.......BK-each cohesion weakening coefficient corresponding to the K soil parameter weakening coefficients; q1，Q2，……，QK-each internal friction angle weakening coefficient corresponding to the K soil parameter weakening coefficients.
As an improvement, in the step (2), the cohesive force weakening coefficient B1Calculating the cohesion value c after weakening1And internal friction angle value
Respectively as follows:
c1＝c0×B1 (1)
in the formula: c. C0-cohesive force, kPa in slope rock-soil mass strength parameters;
-initial value of internal friction angle, degree, in slope rock-soil mass strength parameters; wherein j is 1, 2, … …, K; calculating and analyzing time step A by limit balance method1，A2，A3，......AXCorresponding safety factor F1，F2，F3，......FX(ii) a Taking the minimum value in the safety coefficient, repeating the calculation to obtain the weakening coefficient (B) of the rock-soil body strength parameter1，Qj) Corresponding minimum safety factor F1j，j＝1，2，……，K。
As a refinement, repeating said step (2) in said step (3) to obtain FijWherein i, j ═ 1, 2, …, K; utilizing (B)i，Qj，Fij) And in the formula, i, j is 1, 2, … K, and a contour map of the minimum safety factor of the side slope under the condition of the variation of the cohesive force and the weakening coefficient of the internal friction angle is drawn.
As an improvement, in the step (4), M groups of combined values of cohesive force and internal friction angle weakening coefficient are obtained according to a safety coefficient and side slope minimum safety coefficient contour map suggested by a hydraulic and hydro-power engineering side slope design specification (SL386-2007)
The formulas for calculating the weakened cohesive force value and the weakened internal friction angle value in the step (4) are respectively as follows:
cck＝c0×Bck (3)
in the formula: c. Cck-cohesion value, kPa; b isck-cohesion weakening coefficient;
-internal friction angle value, °;
-internal friction angle weakening coefficient.
The weakened cohesion value c is obtained under the analysis time step corresponding to the minimum safety factor of the side slopeckAnd internal friction angle value
For random variables, N samples T are generated by using a lognormal random distribution method1，T2，……，TNCalculating T by using a response surface method1，T2，……，TNCorresponding safety factor S1，S2，……，SN(ii) a Safety factor Si<1 sample TiFor failure samples, i ═ 1, 2, … …, N, the probability of failure P for the bank slope was calculatedfkThe formula of (1) is:
Pfk＝q/N (5)
in the formula: pfk-calculating a failure probability using the response surface; q-T1，T2，……，TNThe safety factor corresponding to the sample is less than 1 sample total number, and k is 1, 2, … M.
As a refinement, in the step (5), use is made of
And drawing a change curve between the combination value of the cohesive force and the weakening coefficient of the internal friction angle and the failure probability, wherein the combination value of the cohesive force and the weakening coefficient of the internal friction angle corresponding to the minimum failure probability is the maximum weakening coefficient of the cohesive force and the internal friction angle, and k is 1, 2, … M in the formula.
Compared with the prior art, the invention has the advantages that:
the maximum weakening coefficient of the rock-soil body strength parameter of the bank side slope is determined according to the given conditions, the safety consideration on the side slope is increased, and the influence of the rock-soil body strength parameter weakening coefficient on the stability of the side slope is also verified.
Drawings
FIG. 1 is a flow chart of the method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter.
FIG. 2 is a bank side slope model diagram of the method for determining the maximum weakening coefficient of the bank side slope rock-soil mass strength parameter.
FIG. 3 is a contour map of slope minimum safety factors under different soil parameter rock-soil body strength parameter weakening coefficients of the method for determining the bank slope rock-soil body strength parameter maximum weakening coefficient of the invention.
FIG. 4 is a graph of weakening coefficients and failure probability of different rock-soil body strength parameters of the bank slope according to the method for determining the maximum weakening coefficient of the rock-soil body strength parameters of the bank slope.
Detailed Description
The present invention is further illustrated in detail by the following figures 1-4 and examples, which are provided only to illustrate the present invention and are not intended to limit the scope of the present invention.
The technical scheme provided by the invention is as follows:
a bank slope rock-soil body strength parameter maximum weakening coefficient determination method at least comprises the following steps:
(1) establishing a mathematical model;
(2) calculating cohesive force weakening coefficient B1Value of cohesion after weakening of1And internal friction angle value
Will be provided with
Inputting a mathematical model, calculating and analyzing the corresponding safety factors of the time steps, taking the minimum value of the safety factors, repeating the calculation to obtain the minimum safety factor F corresponding to the weakening coefficientij；
(3) Changing the cohesive force weakening coefficient, repeating the step (2), and drawing a contour map of the minimum safety coefficient of the side slope;
(4) calculating a cohesive force value c after weakening according to a safety factor recommended by a hydraulic and hydro-power engineering slope design specification (SL386-2007) and a slope minimum safety factor contour mapckAnd internal friction angle value
Calculating the safety factors and failure probability P corresponding to the N samples under the analysis time step corresponding to the minimum safety factor of the side slopefk；
(5) And drawing a change curve between the weakening coefficient combination value and the failure probability, wherein the weakening coefficient combination value corresponding to the minimum failure probability is the maximum weakening coefficient.
In the mathematical model in the step (1), the reservoir water level descending speed is V, X slope stability analysis time steps are set and recorded as A1，A2，A3，......AXAiming at the cohesion in the strength parameters of reservoir bank slope rock-soil massDesigning K weakening coefficients of force and internal friction angle, and respectively recording the coefficients as B1，B2，B3，.......BKAnd Q1，Q2，……，QK；
Wherein, the V-descending speed is meter/day; x-the number of different time steps set in the slope seepage analysis; a. the1，A2，A3，......AX-each corresponding time step of X time steps of slope seepage analysis; b is1，B2，B3，.......BK-each cohesion weakening coefficient corresponding to the K soil parameter weakening coefficients; q1，Q2，……，QK-each internal friction angle weakening coefficient corresponding to the K soil parameter weakening coefficients.
In the step (2), the cohesive force weakening coefficient B1Calculating the cohesion value c after weakening1And internal friction angle value
Respectively as follows:
c1＝c0×B1 (1)
in the formula: c. C0-cohesive force, kPa in slope rock-soil mass strength parameters;
-initial value of internal friction angle, degree, in slope rock-soil mass strength parameters; wherein j is 1, 2, … …, K; calculating and analyzing time step A by limit balance method1，A2，A3，......AXCorresponding safety factor F1，F2，F3，......FX(ii) a Taking the minimum value in the safety coefficient, repeating the calculation to obtain the weakening coefficient (B) of the rock-soil body strength parameter1，Qj) Corresponding minimum safety factor F1j，j＝1，2，……，K。
Repeating the step (2) in the step (3) to obtain FijWherein i, j ═ 1, 2, …, K; utilizing (B)i，Qj，Fij) And in the formula, i, j is 1, 2, … K, and a contour map of the minimum safety factor of the side slope under the condition of the variation of the cohesive force and the weakening coefficient of the internal friction angle is drawn.
In the step (4), M groups of cohesive force and internal friction angle weakening coefficient combination values are obtained according to the minimum safety factor and the contour map
k is 1, 2, … …, M; the formulas for calculating the weakened cohesive force value and the weakened internal friction angle value in the step (4) are respectively as follows:
cck＝c0×Bck (3)
in the formula: c. Cck-cohesion value, kPa; b isck-cohesion weakening coefficient;
-internal friction angle value, °;
-internal friction angle weakening coefficient.
The weakened cohesion value c is obtained under the analysis time step corresponding to the minimum safety factor of the side slopeckAnd internal friction angle value
For random variables, N samples T are generated by using a lognormal random distribution method1，T2，……，TNCalculating T by using a response surface method1，T2，……，TNCorresponding safety factor S1，S2，……，SN(ii) a Safety factor Si<1 sample TiFor failure samples, i ═ 1, 2, … …N, calculating failure probability P of bank slopefkThe formula of (1) is:
Pfk＝q/N (5)
in the formula: pfk-calculating a failure probability using the response surface; q-T1，T2，……，TNThe safety factor corresponding to the sample is less than 1 sample total number, and k is 1, 2, … M.
In step (5), use is made of
And drawing a change curve between the combination value of the cohesive force and the weakening coefficient of the internal friction angle and the failure probability, wherein the combination value of the cohesive force and the weakening coefficient of the internal friction angle corresponding to the minimum failure probability is the maximum weakening coefficient of the cohesive force and the internal friction angle, and k is 1, 2, … M in the formula.
The present invention will be further described with reference to specific examples.
Example (b):
the bank side slope has a height of 20m and a width of 76m, a side slope included angle of 26.57 degrees and an initial water level of 19m, is composed of homogeneous soil bodies, and has an internal friction angle of the shear strength of the soil bodies
Average value of 30 DEG, standard deviation of 9, cohesion c0The average value is 20kpa, the standard deviation is 6, and the volume weight gamma is 20kN/m3Saturated volume water content of 0.5m3m-3Residual water content of 0.035m3m-3。
The specific implementation steps are as follows:
the method comprises the following steps: establishing a bank slope numerical model by using a Seep/w module in Geo-studio software, setting the falling speed of a bank water level to be 1m/d, the slope stability analysis time step to be 15d, and the storage time step to be 1 d; ten reservoir bank slope rock-soil body strength parameter (cohesive force, internal friction angle) weakening coefficients are designed to be respectively: b is1＝0.1，B2＝0.2，B3＝0.3，B4＝0.4，B5＝0.5，B6＝0.6，B7＝0.7，B8＝0.8，B9＝0.9，B10＝1.0；Q1＝0.1，Q2＝0.2，Q3＝0.3，Q4＝0.4，Q5＝0.5，Q6＝0.6，Q7＝0.7，Q8＝0.8，Q9＝0.9，Q10＝1.0；
Step two: when cohesive force weakening coefficient B10.1, according to formula c1＝c0×B1Calculating the cohesive force value after weakening to be 2kpa according to a formula
10 calculating the internal friction angles after weakening as follows:
respectively to be provided with
Inputting a mathematical model of the bank slope, and respectively calculating the corresponding minimum safety factors in the analysis time step by using a limit balance method: f11＝0.19，F12＝0.3，F13＝0.4，F14＝0.5，F15＝0.61，F16＝0.72，F17＝0.83，F18＝0.95，F19＝1.07，F110＝1.2；
Step three: changing the cohesive force weakening coefficient, and repeating the step two until F is obtainedij(i-1, 2, … …, 10; j-1, 2, … …, 10) using (B)i，Qj，Fij) I, j is 1, 2, … 10, and drawing a contour map of the minimum safety factor of the slope under the condition of changing cohesive force and internal friction angle weakening coefficient;
step four: according to a safety factor F suggested by a hydraulic and hydroelectric engineering slope design specification (SL386-2007), inquiring the weakening coefficients of the strength parameters of the uniform five rock-soil bodies in a slope minimum safety factor contour map as follows: b isc1＝0.3，
Bc2＝0.5，
Bc3＝0.77，
Bc4＝0.9，
Bc5＝1，
According to formula cck＝c0×BckAnd
the calculated cohesive force value and the internal friction angle value after weakening are respectively as follows: c. Cc1＝6kpa，
cc2＝10kpa，
cc3＝15.4kpa，
cc4＝18kpa，
cc5＝20kpa，
Strength parameter c after weakening of a rock-soil massck、
(i 1, 2.. 5) and c under the analysis time step corresponding to the minimum safety factor of the side slopeck、
(i ═ 1, 2.. 5) as random variables, 10 was generated using a log-normal random distribution5Individual soil body parameter sample T1，T2，......，T100000Calculating 10 based on the response surface method5N-10 corresponding to each soil parameter sample5Safety factor, denoted as S1，S2，……，S10000. When N is 105Within a safety factor, if the safety factor Si<1, (i ═ 1, 2, … …, 100000), then called TiFor failure samples, repeating the steps to obtain q failure samples in total, and obtaining the failure samples according to a formula Pfi＝q/105Calculating the failure probability corresponding to the bank side slope;
step five: by using
And drawing a change curve between the combination value of the cohesive force and the internal friction angle weakening coefficient and the failure probability, wherein the combination value of the cohesive force and the internal friction angle weakening coefficient corresponding to the minimum failure probability is the maximum weakening coefficient of the cohesive force and the internal friction angle. As shown in FIG. 4, when the rock-soil body strength parameter is Bc1＝0.3，
Failure probability P corresponding to side slopef1.02 percent; the strength parameter of the rock-soil body is Bc2＝0.5，
Failure probability P corresponding to side slopef0.65%; the strength parameter of the rock-soil body is Bc3＝0.77，
Failure probability P corresponding to side slopef0.29%; the strength parameter of the rock-soil body is Bc4＝0.9，
Failure probability P corresponding to side slopef0.4%; the strength parameter of the rock-soil body is Bc5＝1，
Failure probability P corresponding to side slopef0.25%. According to the safety coefficient and the minimum failure probability suggested by the hydraulic and hydroelectric engineering slope design specification (SL386-2007), the relation curves of the graphs shown in the figures 3 and 4 can be inquired, and the maximum weakening coefficient of the rock-soil body strength parameter of the bank slope is determined; for example, when the safety factor suggested by the design specification of the water conservancy and hydropower engineering side slope (SL386-2007) is 1.326, the minimum failure probability is 0.25%, and the maximum weakening coefficient of the rock-soil body strength parameter of the bank side slope is Bc＝1，
And (3) comparison finding: the influence of the weakening of rock-soil body strength parameters on the stability of the bank slope is often ignored, so that the safety consideration on the slope is not comprehensive enough, under the given reservoir water level descending speed, the invention designs different rock-soil body strength parameter weakening coefficients, calculating the minimum safety factor of the bank slope by using an orthogonal test method and a limit balance method, drawing an contour map, obtaining different rock-soil body strength parameter weakening coefficients according to safety coefficients recommended by hydraulic and hydroelectric engineering slope design specifications (SL386-2007), obtaining a change curve between the different rock-soil body strength parameter weakening coefficients and failure probability by considering variability of the rock-soil body strength parameters, and determining the maximum weakening coefficient of the rock-soil body strength parameter of the bank side slope according to the safety factor and the minimum failure probability suggested by the design specification (SL386-2007) of the water conservancy and hydropower engineering side slope. The engineering example verifies that when the safety coefficient recommended by the hydraulic and hydroelectric engineering side slope design specification (SL386-2007) is 1.326, the side slope failure probability shows the phenomenon that the side slope failure probability is firstly reduced and then increased and then reduced along with the change of the weakening coefficient of the rock-soil body strength parameter, so that the influence of the weakening coefficient of the rock-soil body strength parameter on the side slope stability is fully verified, the maximum weakening coefficient of the reservoir-bank side slope rock-soil body strength parameter can be finally determined according to the safety coefficient and the minimum failure probability recommended by the hydraulic and hydroelectric engineering side slope design specification (SL386-2007), and the effectiveness of the method is verified through example comparative analysis.
The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the embodiments shown in the drawings are only one of the embodiments of the present invention, and the actual embodiments are not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. A bank slope rock-soil body strength parameter maximum weakening coefficient determination method is characterized by comprising the following steps: at least comprises the following steps:
(1) establishing a mathematical model;
(2) calculating cohesive force weakening coefficient B1Value of cohesion after weakening of1And internal friction angle value
Will (c)1，φj) Inputting a mathematical model, calculating and analyzing the corresponding safety factors of the time steps, taking the minimum value of the safety factors, repeating the calculation to obtain the minimum safety factor F corresponding to the weakening coefficient1j；
(3) Changing the cohesive force weakening coefficient, repeating the step (2), and drawing a contour map of the minimum safety coefficient of the side slope;
(4) calculating the weakened cohesive force value c according to the safety factor of the slope design criterion and the slope minimum safety factor contour map of the hydraulic and hydroelectric engineeringckAnd internal friction angle value
Calculating the safety factors and failure probability P corresponding to the N samples under the analysis time step corresponding to the minimum safety factor of the side slopefk；
(5) And drawing a change curve between the weakening coefficient combination value and the failure probability, wherein the weakening coefficient combination value corresponding to the minimum failure probability is the maximum weakening coefficient.
2. The method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter according to claim 1, is characterized in that: in the mathematical model in the step (1), the reservoir water level descending speed is V, X slope stability analysis time steps are set and recorded as A1，A2，A3，......AXDesigning K weakening coefficients aiming at cohesive force and internal friction angle in reservoir bank slope rock-soil body strength parameters, and respectively recording the K weakening coefficients as B1，B2，B3，.......BKAnd Q1，Q2，……，QK；
Wherein, the V-descending speed is meter/day; x-the number of different time steps set in the slope seepage analysis; a. the1，A2，A3，......AX-each corresponding time step of X time steps of slope seepage analysis; b is1，B2，B3，.......BK-each cohesion weakening coefficient corresponding to the K soil parameter weakening coefficients; q1，Q2，……，QK-each internal friction angle weakening coefficient corresponding to the K soil parameter weakening coefficients.
3. The method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter according to claim 1, is characterized in that: in the step (2), the cohesive force weakening coefficient B1Calculating the cohesion value c after weakening1And internal friction angle value
Respectively as follows:
c1＝c0×B1 (1)
in the formula:c0-cohesive force, kPa in slope rock-soil mass strength parameters; phi is a0-initial value of internal friction angle, degree, in slope rock-soil mass strength parameters; wherein j is 1, 2, … …, K; calculating and analyzing time step A by limit balance method1，A2，A3，......AXCorresponding safety factor F1，F2，F3，......FX(ii) a Taking the minimum value in the safety coefficient, repeating the calculation to obtain the weakening coefficient (B) of the rock-soil body strength parameter1，Qj) Corresponding minimum safety factor F1j，j＝1，2，……，K。
4. The method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter according to claim 1, is characterized in that: repeating the step (2) in the step (3) to obtain FijWherein i, j ═ 1, 2, …, K; utilizing (B)i，Qj，Fij) And in the formula, i, j is 1, 2, … K, and a contour map of the minimum safety factor of the side slope under the condition of the variation of the cohesive force and the weakening coefficient of the internal friction angle is drawn.
5. The method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter according to claim 1, is characterized in that: in the step (4), M groups of cohesive force and internal friction angle weakening coefficient combination values are obtained according to a safety coefficient and side slope minimum safety coefficient contour map suggested by a hydraulic and hydroelectric engineering side slope design specification (SL386-2007)
k is 1, 2, … …, M; the formulas for calculating the weakened cohesive force value and the weakened internal friction angle value in the step (4) are respectively as follows:
cck＝c0×Bck (3)
in the formula: c. Cck-viscosityA value of force, kPa; b isck-cohesion weakening coefficient;
an internal friction angle value;
internal friction angle weakening coefficient.
The weakened cohesion value c is obtained under the analysis time step corresponding to the minimum safety factor of the side slopeckAnd internal friction angle value
For random variables, N samples T are generated by using a lognormal random distribution method1，T2，……，TNCalculating T by using a response surface method1，T2，……，TNCorresponding safety factor S1，S2，……，SN(ii) a Safety factor Si<1 sample TiFor failure samples, i ═ 1, 2, … …, N, the probability of failure P for the bank slope was calculatedfkThe formula of (1) is:
Pfk＝q/N (5)
in the formula: pfk-calculating a failure probability using the response surface; q-T1，T2，……，TNThe safety factor corresponding to the sample is less than 1 sample total number, and k is 1, 2, … M.
6. The method for determining the maximum weakening coefficient of the bank slope rock-soil body strength parameter according to claim 1, is characterized in that: in the step (5), use is made of
And drawing a change curve between the combination value of the cohesive force and the weakening coefficient of the internal friction angle and the failure probability, wherein the combination value of the cohesive force and the weakening coefficient of the internal friction angle corresponding to the minimum failure probability is the maximum weakening coefficient of the cohesive force and the internal friction angle, and k is 1, 2, … M in the formula.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111480644.1A CN114357718A (en) | 2021-12-06 | 2021-12-06 | Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111480644.1A CN114357718A (en) | 2021-12-06 | 2021-12-06 | Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114357718A true CN114357718A (en) | 2022-04-15 |
Family
ID=81098190
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111480644.1A Pending CN114357718A (en) | 2021-12-06 | 2021-12-06 | Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114357718A (en) |
-
2021
- 2021-12-06 CN CN202111480644.1A patent/CN114357718A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11542801B2 (en) | Optimized design method for temporary blocking agent to promote uniform expansion of fractures produced by fracturing in horizontal wells | |
| CN111310392B (en) | Method for evaluating unstable area amplification effect of foundation pit excavation slope | |
| CN110147561B (en) | Method for predicting volume fracture network of tight oil and gas reservoir containing natural fracture | |
| CN109271744B (en) | Dump base bearing capacity calculation method based on limit upper limit method | |
| Richardson | Investigations of threshold effects in soil deformations | |
| Li et al. | One-dimensional consolidation of double-layered soil with non-Darcian flow described by exponent and threshold gradient | |
| CN111963158A (en) | Method for calculating permeability of matrix after acid fracturing of carbonate rock | |
| CN110705087A (en) | Construction method of rock discrete element sample containing closed stress | |
| Nemat-Nasser et al. | Liquefaction and fabric of sand | |
| CN114814165A (en) | Method and device for evaluating shear failure of sandy seabed under action of solitary wave | |
| CN109763812B (en) | Hydrate exploitation mechanical stability quantitative analysis method based on mole-coulomb theory | |
| CN114357718A (en) | Method for determining maximum weakening coefficient of bank slope rock-soil body strength parameter | |
| CN116522663B (en) | Karst roof safety thickness calculation method, system, equipment and storage medium | |
| Kwan et al. | Comparison between shear strength of dry sand measured in CSS device using wire-reinforced membranes and stacked rings | |
| CN113239435B (en) | Method for determining optimal water discharge speed of reservoir | |
| CN113887074A (en) | Novel method for determining optimal slope angle of upstream side slope of reservoir dam | |
| CN113158314B (en) | Slope stability analysis method | |
| Ridgway et al. | Modelling of the void space of tablets compacted over a range of pressures | |
| CN112541257B (en) | Method for calculating service life of limestone slope based on corrosion rate | |
| Xie et al. | Nonlinear analytical solution for one-dimensional consolidation of soft soil under cyclic loading | |
| LI et al. | Bearing behavior and accumulated rotation of modified suction caisson (MSC) in saturated sand under cyclic loading | |
| CN116644677B (en) | DEM-based coal-rock mass hydraulic fracturing anti-reflection effect quantification method | |
| Abdul-Husain | Comparative study of theoretical methods for estimating pile capacity using 1-g model pile tests in cohesionless soil | |
| Ninghot et al. | Analysis of circular footing subjected to vertical load using MIDAS 3D | |
| CN114036867B (en) | Discrete element microscopic parameter calibration method and system for landslide accumulation broken stone material |
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 |