Method for evaluating impact force of waves on straight wall type rock bank slope

Abstract

The invention provides a method for evaluating the impact force of waves on a straight wall type rock bank slope. The method comprises the following steps: S1, constructing a numerical model according to the main form of the straight wall type rock bank slope; s2, setting boundary conditions for the numerical model according to an actual marine environment; s3, selecting a numerical calculation method suitable for the interaction of the waves and the rock bank slope to set a numerical simulation program; s4, operating a numerical simulation program to simulate the stress-strain reaction of the rock bank slope under the action of waves; s5, analyzing a numerical simulation result in combination with a standard calculation result; and S6, the impact force of waves on the straight wall type rock bank slope is evaluated according to the actual working conditions. According to the method, the impact force of the wave on the straight wall type rock bank slope can be simulated and calculated by using a numerical simulation method, and the impact force of the wave on the straight wall type rock bank slope is evaluated according to a standard calculation result and an actual working condition; a more normative, effective and intuitive evaluation method is provided for evaluating the influence of waves on the stability of the rock bank slope and treating the rock bank slope to guide the actual ocean engineering construction work.

Description

Technical Field

[0001] The present invention relates to the field of marine engineering geological technology, and specifically to a method for evaluating the impact force of waves on a straight-wall rocky slope. Background Art

[0002] With the rapid development of the country's economy and society, the scale of marine resource exploration and construction is constantly expanding, and gradually developing from shallow sea areas to deep sea areas. During the construction and operation of the project, it is essential to assess the possible geological disasters in the surrounding marine environment. Among them, the geological disasters caused by wave impact that lead to the instability of the rock slopes around the marine project need to be paid great attention.

[0003] One of the causes of the hydrodynamic triggering mechanism of marine geological disasters is that waves are generated by natural factors of marine climate such as storms. During their movement, they will continuously exert normal stress and shear stress on the ocean slope, affecting the stability of the rock slope, and eventually causing damage to the internal structure of the slope and landslides. The impact of wave impact on the stability of rock slopes is mainly due to two points: first, the cyclic impact of waves on the slope surface of the rock slope. Under this action, transient pore water pressure and residual pore water pressure are generated inside the rock mass. The accumulation of internal excess pore water pressure causes significant changes in internal stress; second, the weakening effect of waves on the structural surface, which is reflected in the low-frequency and long-term repeated action of waves on the rock slope. Under the influence of long-term cyclic stress on the rock mass and its structural surface, its physical and chemical properties have changed, reducing the strength and deformation modulus of the rock. Waves mainly affect the internal structure of the rock slope, which is not easy to observe and once damage occurs, it is extremely harmful, seriously threatening the safety of life and property of marine engineering and workers related to the slope.

[0004] However, the current research on slope stability analysis under the influence of waves is mainly focused on soil slopes. Although a series of research results have been obtained in this regard, the evaluation of wave impact on rock slopes is relatively small, and there is also a lack of comparative research on standard calculation results and numerical simulation results. The evaluation of wave impact on straight wall rock slopes requires a more standardized and effective evaluation method to guide actual marine engineering construction work. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a method for evaluating the impact force of waves on straight-wall rock slopes, which uses standard calculation method and numerical simulation method to calculate and analyze the wave action on the rock slope, and finally conducts comparative analysis to select the calculation results to solve the problem of less relevant evaluation content and lack of comparative reference, so as to effectively and quickly determine the force of waves on the straight-wall rock slopes.

[0006] The technical solution adopted by the present invention is a method for evaluating the impact force of waves on a straight wall rock slope. The method accurately evaluates the impact force of waves on a rock slope by combining the construction of a three-dimensional numerical model and standard calculation, and comprises the following steps:

[0007] Step S1: construct a three-dimensional numerical model according to the geometric shape, structural characteristics and geological composition of the straight wall rock slope to simulate the geometric shape and physical characteristics of the slope structure;

[0008] Step S2: according to the actual marine environment conditions and wave characteristics, the boundary conditions of the numerical model are set, including wave parameters, slope material properties and surrounding environmental factors;

[0009] Step S3: Select a numerical calculation method suitable for the interaction between waves and rocky slopes, and set the calculation method and parameters of the numerical simulation program, including the numerical method used and the time step;

[0010] Step S4: running a numerical simulation program to simulate the stress-strain response of the rock slope under the action of waves, and obtaining pore water pressure and stress distribution data;

[0011] Step S5: Analyze the numerical simulation results in combination with the standard calculation results, compare and verify the accuracy of the numerical simulation results, and adjust the model parameters to optimize the results;

[0012] Step S6: Based on the simulation results and actual working conditions, the impact force of waves on the straight-wall rock slope is evaluated, and targeted suggestions are provided for engineering design and safety protection.

[0013] Preferably, in step S1, the method for constructing a three-dimensional numerical model includes establishing a 1:1 restored numerical model of wave propagation and straight-wall rock slope using numerical simulation software (such as Flow-3D program, MIKE 21 program and SWAN program, etc.) according to the main forms of the straight-wall rock slope and considering actual conditions, and simultaneously inputting wave characteristics, the geometric shape of the straight-wall rock slope and material property parameters.

[0014] Preferably, in step S2, the boundary conditions of the numerical model include important numerical simulation setting options of wave source input, water depth distribution, geometric shape of straight wall rock slope, and bottom friction coefficient.

[0015] Preferably, in step S3, the calculation method and parameters are set to selected specifications and formulas, and the impact force of the wave on the model is calculated in combination with the wave parameters and the geometric shape of the model.

[0016] Preferably, in step S3, the formula selected by the calculation method is based on the impact force calculation part of the specification "Harbor Hydrology Specification" (JTS145-2-2013) and is calculated according to the following steps:

[0017] Determine the wave state of waves acting on a vertical rocky bank slope;

[0018] Calculate the impact force on the straight-wall rock slope under the action of wave crests and troughs.

[0019] Preferably, in step S3, the wave state of the wave acting on the straight wall rock slope is determined according to the slope and wave conditions. The generation condition of the standing wave should satisfy that the crest line is roughly parallel to the slope, and the slope length is greater than one wavelength, and also needs to satisfy the following formula:

[0020]

[0021]

[0022] Where: ——Average wave period (s); d——Water depth in front of the bank slope (m); H——Height of the wave at the bank slope (m); g——Gravity acceleration (m / s 2 ).

[0023] Preferably, the impact force on the straight wall rock slope under the action of the wave crest and the wave trough includes selecting corresponding formulas according to the characteristics of the slope and the wave to calculate respectively:

[0024] When d≥1.8H and d / L=0.05~0.12 (L is the wavelength), the impact force under the action of the wave crest can be calculated according to the shock wave pressure distribution diagram under the action of the wave crest in the specification "Harbor Hydrology Specification" (JTS145-2-2013) according to the following provisions:

[0025] ① The wave surface elevation is calculated according to the following formula:

[0026]

[0027]

[0028]

[0029]

[0030] Where: η c —— wave surface elevation (m); d—— water depth in front of the bank slope (m); B η , m——correction coefficient; T * ——dimensionless period(s); ——average period (s); g——gravitational acceleration (m / s 2 );

[0031] ②h above the still water surface cThe slope wave pressure intensity at the location is given by formula (7) ～ (9) Calculation:

[0032]

[0033] n=[0.636618+4.23264(H / d) 1.67 ,1.0] (9)

[0034] Where: h c ——wave pressure intensity p ac Position of the point of action above the still water surface (m); p ac ——with h c The corresponding slope wave pressure intensity (kPa); n is the index of the wave pressure intensity distribution curve above the still water surface, and its value is the larger of the two numbers in the formula; p oc ——wave pressure intensity on the still water surface (kPa); γ——weight of water (kN / m 3 );

[0035] ③ Wave pressure intensity p on the still water surface oc The wave pressure intensity of other characteristic points on the slope is calculated according to formula (10). bc >p oc , take p bc =p oc , where p bc is the slope wave pressure intensity corresponding to the water depth of d / 2 (kPa):

[0036]

[0037] Where: p is the wave pressure intensity at each characteristic point on the slope (kPa); A p , B p , q——peak action coefficient, determined according to the corresponding parameter table;

[0038] ④ Horizontal total wave force P on the slope per unit length c (kN / m) is calculated according to formula (11):

[0039]

[0040] Where: P c ——total horizontal wave force on the slope per unit length (kN / m); pd c ——wave pressure intensity at the bottom of the slope (kPa); pb c ——slope wave pressure intensity corresponding to the water depth d / 2 (kPa);

[0041] ⑤ Horizontal total wave moment on the slope per unit length M c (kN·m / m) is calculated according to formula (12):

[0042]

[0043] Where: M c ——horizontal total wave moment on the slope per unit length (kN·m / m);

[0044] ⑥ Wave buoyancy force P on the bottom of the slope per unit length uc (kN / m) is calculated according to formula (13):

[0045]

[0046] Where: P uc ——wave buoyancy force per unit length on the bottom surface of the slope (kN / m); B——slope bottom width (m);

[0047] d≥1.8H and d / L=0.05 ～ When the impact force under the trough effect is 0.12, the impact force under the trough effect can be calculated according to the following provisions based on the shock wave pressure distribution diagram under the trough effect in the "Harbor Hydrology Code" (JTS145-2-2013):

[0048] ① Wave trough height η t Calculate according to formula (14):

[0049]

[0050] Where: η t ——wave trough height (m); A p , B p , q——trough effect coefficient, which can be determined according to the parameter table of the specification "Seaport Hydrological Specifications" (JTS145-2-2013);

[0051] ② The wave pressure intensity p at each characteristic point on the slope is calculated according to (15), and the coefficient A p , B p , q is determined according to the corresponding parameter table, when p dt >p ot When p dt =p ot , where p dt is the wave pressure intensity at the bottom of the slope (kPa); p ot is the wave pressure intensity corresponding to the wave trough surface (kPa):

[0052] p=A p +B p (H / d) q (15)

[0053] Where: p——wave pressure intensity at each characteristic point on the slope surface (kPa);

[0054] ③The total horizontal wave force P on the slope per unit length t Calculate according to formula (16):

[0055]

[0056] Where: P t ——horizontal total wave force per unit length of slope (kN / m); dt ——wave pressure intensity at the bottom of the slope (kPa); p ot ——wave pressure intensity corresponding to the wave surface at the trough (kPa);

[0057] ④ The downward wave force P on the bottom of the slope per unit length ut Calculate according to formula (17):

[0058]

[0059] Where: P ut ——downward wave force on the bottom of the slope per unit length (kN / m); p dt ——wave pressure intensity at the bottom of the slope (kPa); B——width of the bottom of the slope (m);

[0060] d≥1.8H, 0.12≤d / L<0.139 and 8 <T * When ≤9, the wave pressure and wave surface elevation can be calculated according to the following formulas (18) and (19):

[0061]

[0062]

[0063] Where: T * ——dimensionless period under actual wave conditions; X T* ——Represents various values ​​such as wave pressure and wave surface height; ——T * =8 and the H / d value of the actual wave; ——T * =9 and the H / d value of the actual wave conditions.

[0064] Preferably, in step S4, the operation of the numerical simulation program includes:

[0065] Use numerical simulation programs to simulate wave propagation, reflection, refraction, and interference around breakwaters;

[0066] A numerical simulation program is used to calculate wave height, wave pressure, wave velocity parameters and the interaction between waves and vertical rock slopes, and finally obtain specific impact force results.

[0067] Preferably, in step S5, the analysis of the numerical simulation results includes comparing the differences between the standard calculation results and the numerical simulation calculation results, specifically by calculating the impact force results under different working conditions, and analyzing the differences between the impact force results calculated by the two methods, so as to further carry out analysis.

[0068] Preferably, in step S6, the evaluation of the impact force of waves on the straight-wall rock slope includes evaluating and analyzing the calculation results of the wave impact force in combination with actual working conditions and the needs of marine engineering construction, and using this as a reference for actual engineering construction.

[0069] It can be seen from the above technical solution that the beneficial technical effects of the present invention are as follows:

[0070] In this method, a high-precision numerical model is established to carry out numerical simulation calculations on specific examples. The results of different working conditions are compared with the results of corresponding standard calculations to ensure the accuracy and rationality of the evaluation results. The impact force of waves on straight-wall rock slopes can be evaluated more standardized and effectively. The water pressure cloud map derived from the numerical simulation program can more intuitively analyze the impact of the impact force and provide a reference for local marine engineering construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 is a calculation flow chart of a method for evaluating the impact force of waves on a straight-wall rocky slope according to an embodiment of the present invention;

[0072] Figure 2 The relationship between the water depth, wave height and wavelength of the embodiment of the present invention is d≥1.8H and d / L=0.05~0.12, and the shock wave pressure distribution diagram when the wave crest acts;

[0073] Figure 3 The relationship between the water depth, wave height and wavelength of the embodiment of the present invention is d≥1.8H and d / L=0.05~0.12, and the pressure distribution diagram of the shock wave when the trough acts;

[0074] Figure 4 is a schematic cloud diagram of water pressure when the numerical simulation time is 36 seconds in an embodiment of the present invention;

[0075] Figure 5 is a comparison chart of working conditions 1-5 and calculation results of an embodiment of the present invention;

[0076] Figure 6 4 is a comparative distribution diagram of the water pressure calculation results of an embodiment of the present invention. DETAILED DESCRIPTION

[0077] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0078] This example takes a vertical rock slope in the southeastern coast of China as the evaluation object. Figure 1 The embodiment of the present invention provides a method for evaluating the impact force of waves on a straight wall rock slope, comprising the following steps:

[0079] Step 1: Construct a numerical model based on the main morphology of the straight-wall rock slope.

[0080] The numerical simulation program uses Flow-3D software. In the program, choose to add a physical model and build a calculation model of a straight wall rock slope based on the characteristic parameters of the wave (such as wave height, wavelength, etc.), the geometric shape of the model, and material properties. The specific settings of the numerical simulation model are as follows:

[0081] (1) Size and structure. In order to make the waves stable in the time and space segments of the data reading, and to make the distance between the boundary and the structure far enough so that the waves move naturally in the Y direction, the length of the wave flume is 200m, and the rock slope is placed at the back. At this distance, the boundary will not affect the wave state. The height of the flume is 10m to ensure that the range of wave movement is completely contained in the calculation grid area. The structure is a straight wall type with a height of 25m and a bottom width of 10m.

[0082] (2) Physical model setting: In the simulation of this embodiment, the fluid is set to free surface flow and incompressible flow; the number of fluids is a single fluid; the physical model is selected as gravity and non-inertial reference system, viscosity and turbulence model.

[0083] (3) Fluid parameter settings. In this simulation, the fluid is set as a viscous fluid, the turbulence model is set as the ke two-equation model, the maximum turbulent mixing length is dynamically calculated, the wall shear boundary condition is set as a no-slip condition, and the friction coefficient is set to -1. At the same time, the water temperature is set to 20°C.

[0084] (4) Grid division. In this simulation, a three-dimensional grid is set, where the X-axis coordinate is 0 to 200 meters, the Y-axis coordinate is 0 to 1 meter, and the Z-axis coordinate is 0 to 25 meters, with a total of 125,000 grids. min The boundary condition is set as a wave boundary, and the water surface elevation is set to 10 meters. max The boundary conditions are set to specified pressure conditions, where the fluid fraction is set to 0, indicating an air interface. This setting can more accurately simulate the interaction between waves and fluid.

[0085] Step 2: Set boundary conditions for the numerical model according to actual conditions.

[0086] The boundary condition setting of the numerical model requires the selection of boundary type to be applicable to the selected boundary and the setting of properties related to the boundary type.

[0087] (1) X direction

[0088] The simulation X of this embodiment min The boundary type is set to wave boundary, which is described by Stokes waves and Cnoidal waves. The fluid height is set to 10m, X max The boundary condition is wall boundary.

[0089] (2)Y direction

[0090] Y min Setting the boundary to a symmetry boundary can avoid the error of reflection of waves when they are incident obliquely on the slope during simulation. Symmetry boundaries can simulate the symmetric flow characteristics of actual flows very well, reducing the computational workload. Using symmetry can not only reduce storage space, but also retain complete calculation results.

[0091] (3) Z direction

[0092] Z max The boundary condition is a specified pressure boundary with a fluid fraction of 0, i.e., an air interface. This can reduce the friction at the bottom boundary of the numerical model, prevent a significant attenuation of the wave height, and make the wave height at the structure roughly the same as at the incident point, ensuring that the simulation is more consistent with the actual waves.

[0093] Step 3: Set the calculation method of the numerical simulation program.

[0094] In order to ensure that the calculation results of the numerical simulation program are more referenceable, the standard calculation is carried out for comparison. For the convenience of calculation, the calculation formula is input into the Matlab program to assist the calculation. The calculation formula of the numerical simulation and standard calculation is based on the impact force calculation part of the standard "Harbor Hydrology Code" (JTS145-2-2013), and the calculation is carried out according to the following steps:

[0095] Determine the wave state of waves acting on a vertical rocky bank slope;

[0096] Calculate the impact force on the straight-wall rock slope under the action of wave crests and troughs.

[0097] (1) The wave state of waves acting on a vertical rocky bank slope is determined based on the bank slope and wave conditions. The conditions for the generation of standing waves should satisfy that the wave crest line is roughly parallel to the bank slope and the bank slope length is greater than one wavelength. At the same time, the following formula must be satisfied:

[0098]

[0099]

[0100] Where: ——Average wave period (s); d——Water depth in front of the bank slope (m); H——Height of the wave at the bank slope (m); g——Gravity acceleration (m / s 2 ).

[0101] (2) The impact force on the straight rock slope under the action of wave crests and troughs is calculated by selecting the corresponding formulas based on the characteristics of the slope and waves:

[0102] See also Figure 2 , when d≥1.8H and d / L=0.05~0.12 (L is the wavelength), the impact force under the action of the wave crest can be calculated according to the shock wave pressure distribution diagram under the action of the wave crest according to the following provisions:

[0103] ①The wave surface elevation is calculated according to the following formula

[0104]

[0105]

[0106]

[0107]

[0108] Where: η c —— wave surface elevation (m); d—— water depth in front of the bank slope (m); B η , m——correction coefficient; T * ——dimensionless period(s); ——average period (s); g——gravitational acceleration (m / s 2 ).

[0109] ②h above the still water surface c The slope wave pressure intensity at the location is given by formula (7) ～ (9) Calculation

[0110]

[0111]

[0112] n=[0.636618+4.23264(Hld) 1.67 ,1.0] (9)

[0113] Where: h c ——wave pressure intensity p ac Position of the point of action above the still water surface (m); p ac ——with hc The corresponding slope wave pressure intensity (kPa); n is the index of the wave pressure intensity distribution curve above the still water surface, and its value is the larger of the two numbers in the formula; p oc ——wave pressure intensity on the still water surface (kPa); γ——weight of water (kN / m 3 ).

[0114] ③ Wave pressure intensity p on the still water surface oc The wave pressure intensity of other characteristic points on the slope is calculated according to formula (10). bc >p oc , take p bc =p oc , where p bc is the slope wave pressure intensity corresponding to the water depth of d / 2 (kPa);

[0115]

[0116] Where: p is the wave pressure intensity at each characteristic point on the slope (kPa); A p , B p , q——peak action coefficient, determined according to the corresponding parameter table.

[0117] ④ Horizontal total wave force P on the slope per unit length c (kN / m) is calculated according to formula (11);

[0118]

[0119] Where: P c ——total horizontal wave force on the slope per unit length (kN / m); p dc ——wave pressure intensity at the bottom of the slope (kPa); p bc ——Slope wave pressure intensity corresponding to water depth d / 2 (kPa).

[0120] ⑤ Horizontal total wave moment on the slope per unit length M c (kN·m / m) is calculated according to formula (12);

[0121]

[0122] Where: M c ——Total horizontal wave moment on the slope per unit length (kN·m / m).

[0123] ⑥ Wave buoyancy force P on the bottom of the slope per unit length uc (kN / m) is calculated according to formula (13).

[0124]

[0125] Where: Puc ——wave buoyancy on the slope bottom per unit length (kN / m); B——slope bottom width (m).

[0126] See also Figure 3 , when d≥1.8H and d / L=0.05~0.12, the impact force under the trough action can be calculated according to the following provisions based on the shock wave pressure distribution diagram when the trough action occurs:

[0127] ① Wave trough height η t Calculate according to formula (14):

[0128]

[0129] Where: η t ——wave trough height (m); A p , B p , q——trough action coefficient, which can be determined according to the parameter table of the specification "Harbor Hydrology Specification" (JTS145-2-2013).

[0130] ② The wave pressure intensity p at each characteristic point on the slope is calculated according to (15), and the coefficients Ap, Bp, and q are determined according to the corresponding parameter table. dt >p ot When p dt =p ot , where p dt is the wave pressure intensity at the bottom of the slope (kPa); p ot is the wave pressure intensity corresponding to the wave surface at the trough (kPa);

[0131] p=A p +B p (H / d) q (15)

[0132] Where: p is the wave pressure intensity at each characteristic point on the slope (kPa).

[0133] ③The total horizontal wave force P on the slope per unit length t Calculate according to formula (16);

[0134]

[0135] Where: P t ——horizontal total wave force per unit length of slope (kN / m); pd t ——wave pressure intensity at the bottom of the slope (kPa); po t ——Wave pressure intensity corresponding to the wave surface at the trough (kPa).

[0136] ④ The downward wave force P on the bottom of the slope per unit length utCalculate according to formula (17).

[0137]

[0138] Where: P ut ——downward wave force on the bottom of the slope per unit length (kN / m); p dt ——wave pressure intensity at the bottom of the slope (kPa); B——width of the bottom of the slope (m).

[0139] d≥1.8H, 0.12≤d / L<0.139 and 8 <T * When ≤9, the wave pressure and wave surface elevation can be calculated according to the following formulas (18) and (19):

[0140]

[0141]

[0142] Where: T * ——dimensionless period under actual wave conditions; ——Represents various values ​​such as wave pressure and wave surface height; ——T * =8 and the H / d value of the actual wave; ——T * =9 and the H / d value of the actual wave conditions.

[0143] Step 4: Run the numerical simulation program for calculation.

[0144] See also Figure 4 In order to allow the simulated waves impacting the bank to have enough time to stabilize without being affected by wave reflection, the calculation time is set to 40 seconds. In order to accurately find the position of the wave crest and trough, the data output interval is set to 2 seconds. The calculation results and water pressure cloud maps are output at 8 seconds, 12 seconds, 16 seconds, 20 seconds, 24 seconds, 28 seconds, and 36 seconds respectively.

[0145] Because the moment of interaction between waves and the slope is 36 seconds ago, there will be reflection when the waves hit the slope, and the generated reflected waves will interfere with the incident waves, and the wave shape and water pressure distribution in the water are not stable. According to the numerical simulation results, the waveform of the waves near the slope is relatively regular and stable, that is, the wave shape and water pressure distribution at the time of 36 seconds are selected for analysis.

[0146] Step 5: Analyze the numerical simulation results in combination with the standard calculation results.

[0147] See also Figure 5In order to ensure that the calculation results are more comparative and referenceable, the differences between the impact force results calculated by the two methods are compared by calculating different working conditions, so as to carry out further analysis. There are 5 working conditions, namely working condition 1: d = 10m, H = 4m, L = 160m; working condition 2: d = 10m, H = 5m, L = 142m; working condition 3: d = 10m, H = 3m, L = 170m; working condition 4: d = 15m, H = 2m, L = 150m; working condition 5: d = 15m, H = 3m, L = 170m. It can be seen from the calculation results that the results of the standard calculation are generally smaller, and the values ​​of the numerical simulation calculation results are 3-5.5 times the results of the standard calculation.

[0148] Step 6: Evaluate the impact force of waves on the vertical rock slope according to actual working conditions.

[0149] See also Figure 5 and Figure 6 The calculation results of the standard calculation are conservative in numerical terms. Considering the actual construction requirements of marine engineering and the complex marine environment, the standard calculation is actually less safe than the results of numerical simulation. The numerical simulation method can obtain a water pressure cloud map, which can better analyze the impact of waves on straight wall rock slopes. It is more intuitive and more in line with engineering needs than standard calculations. Therefore, the formula for calculating wave impact force in this embodiment is fitted based on the numerical simulation results:

[0150]

[0151] Where: p bc ——wave impact intensity (kPa); d——water depth in front of the slope (m); H——wave height at the slope (m); L——wave wavelength (m).

[0152] This conclusion and formula are used as a reference for the evaluation of wave impact straight wall rock slope in actual engineering construction in the area of ​​this embodiment.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A method for evaluating the impact force of waves on a straight rocky bank slope, characterized in that: This method combines the construction of a three-dimensional numerical model with standard calculations to accurately evaluate the impact of waves on rocky slopes. It includes the following steps: Step S1: construct a three-dimensional numerical model according to the geometric shape, structural characteristics and geological composition of the straight wall rock slope to simulate the geometric shape and physical characteristics of the slope structure; Step S2: according to the actual marine environment conditions and wave characteristics, the boundary conditions of the numerical model are set, including wave parameters, slope material properties and surrounding environmental factors; Step S3: Select a numerical calculation method suitable for the interaction between waves and rocky slopes, and set the calculation method and parameters of the numerical simulation program, including the numerical method used and the time step; Step S4: running a numerical simulation program to simulate the stress-strain response of the rock slope under the action of waves, and obtaining pore water pressure and stress distribution data; Step S5: Analyze the numerical simulation results in combination with the standard calculation results, compare and verify the accuracy of the numerical simulation results, and adjust the model parameters to optimize the results; Step S6: Based on the simulation results and actual working conditions, the impact force of waves on the straight-wall rock slope is evaluated, and targeted suggestions are provided for engineering design and safety protection.

2. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 1, characterized in that: In step S1, the method for constructing a three-dimensional numerical model includes using numerical simulation software to establish a 1:1 restored numerical model of wave propagation and the straight-wall rock slope based on the main forms of the straight-wall rock slope and considering actual conditions, and simultaneously inputting wave characteristics, the geometric shape of the straight-wall rock slope and material property parameters.

3. The method for evaluating the impact force of waves on a straight rocky slope according to claim 1, characterized in that: In step S2, the boundary conditions of the numerical model include important numerical simulation setting options such as wave source input, water depth distribution, geometric shape of the straight wall rock slope, and bottom friction coefficient.

4. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 1, characterized in that: In step S3, the calculation method and parameters are set to the selected specifications and formulas, and the impact force of the wave on the model is calculated in combination with the wave parameters and the geometric shape of the model.

5. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 4, characterized in that: In step S3, the formula selected by the calculation method is based on the impact force calculation part of the specification "Harbor Hydrology Specification" (JTS145-2-2013) and is calculated according to the following steps: Determine the wave state of waves acting on a vertical rocky bank slope; Calculate the impact force on the straight-wall rock slope under the action of wave crests and troughs.

6. A method for evaluating the impact force of waves on a straight rocky bank slope according to claim 5, characterized in that: In step S3, the wave state of the wave acting on the straight wall rock slope is determined according to the slope and wave conditions. The generation condition of the standing wave should meet the conditions that the crest line is roughly parallel to the slope and the slope length is greater than one wavelength, and the following formula should also be satisfied: Where: ——Average wave period (s); d——Water depth in front of the bank slope (m); H——Height of the wave at the bank slope (m); g——Gravity acceleration (m / s 2 ).

7. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 5, characterized in that: In step S3, the impact force on the straight wall rock slope under the action of the wave crest and the wave trough is calculated by selecting corresponding formulas according to the characteristics of the slope and the wave: When d≥1.8H and d / L=0.05~0.12 (L is the wavelength), the impact force under the action of the wave crest can be calculated according to the shock wave pressure distribution diagram under the action of the wave crest in the specification "Harbor Hydrology Specification" (JTS145-2-2013) according to the following provisions: ① The wave surface elevation is calculated according to the following formula: Where: η c —— wave surface elevation (m); d—— water depth in front of the bank slope (m); B η , m——correction coefficient; T * ——dimensionless period(s); ——average period (s); g——gravitational acceleration (m / s 2 ); ②h above the still water surface c The slope wave pressure intensity at is calculated according to equations (7) to (9): n=[0.636618+4.23264(H / d) 1.67 ,1.0] (9) Where: h c ——wave pressure intensity p ac Position of the point of action above the still water surface (m); p ac ——with h c The corresponding slope wave pressure intensity (kPa); n is the index of the wave pressure intensity distribution curve above the still water surface, and its value is the larger of the two numbers in the formula; p oc ——wave pressure intensity on the still water surface (kPa); γ——weight of water (kN / m 3 ); ③ Wave pressure intensity p on the still water surface oc The wave pressure intensity of other characteristic points on the slope is calculated according to formula (10). bc >p oc , take p bc =p oc , where p bc is the slope wave pressure intensity corresponding to the water depth of d / 2 (kPa): Where: p is the wave pressure intensity at each characteristic point on the slope (kPa); A p , B p , q——peak action coefficient, determined according to the corresponding parameter table; ④ Horizontal total wave force P on the slope per unit length c (kN / m) is calculated according to formula (11): Where: P c ——total horizontal wave force on the slope per unit length (kN / m); p dc ——wave pressure intensity at the bottom of the slope (kPa); p bc ——slope wave pressure intensity corresponding to the water depth d / 2 (kPa); ⑤ Horizontal total wave moment on the slope per unit length M c (kN·m / m) is calculated according to formula (12): Where: M c ——horizontal total wave moment on the slope per unit length (kN·m / m); ⑥ Wave buoyancy force P on the bottom of the slope per unit length uc (kN / m) is calculated according to formula (13): Where: P uc ——wave buoyancy force per unit length on the bottom surface of the slope (kN / m); B——slope bottom width (m); When d≥1.8H and d / L=0.05~0.12, the impact force under the trough action can be calculated according to the following provisions based on the shock wave pressure distribution diagram under the trough action in the specification "Harbor Hydrology Specification" (JTS145-2-2013): ① Wave trough surface elevation η t Calculate according to formula (14): Where: η t ——wave trough height (m); A p , B p , q——trough action coefficient, which can be determined according to the parameter table of the specification "Seaport Hydrological Specifications" (JTS145-2-2013); ② The wave pressure intensity p at each characteristic point on the slope is calculated according to (15), and the coefficient A p , B p , q is determined according to the corresponding parameter table, when p dt >p ot When p dt =p ot , where p dt is the wave pressure intensity at the bottom of the slope (kPa); p ot is the wave pressure intensity corresponding to the wave trough surface (kPa): p=A p +B p (H / d) q (15) Where: p is the wave pressure intensity at each characteristic point on the slope surface (kPa); ③The total horizontal wave force P on the slope per unit length t Calculate according to formula (16): Where: P t ——horizontal total wave force per unit length of slope (kN / m); dt ——wave pressure intensity at the bottom of the slope (kPa); p ot ——wave pressure intensity corresponding to the wave surface at the trough (kPa); ④ The downward wave force P on the bottom of the slope per unit length ut Calculate according to formula (17): Where: P ut ——downward wave force on the bottom of the slope per unit length (kN / m); p dt ——wave pressure intensity at the bottom of the slope (kPa); B——width of the bottom of the slope (m); d≥1.8H, 0.12≤d / L<0.139 and 8 <T * When ≤9, the wave pressure and wave surface elevation can be calculated according to the following formulas (18) and (19): Where: T * ——dimensionless period under actual wave conditions; X T* ——Represents various values ​​such as wave pressure and wave surface height; ——T * =8 and the H / d value of the actual wave; ——T * =9 and the H / d value of the actual wave conditions.

8. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 1, characterized in that: In step S4, the operation of the numerical simulation program includes: Use numerical simulation programs to simulate wave propagation, reflection, refraction, and interference around breakwaters; A numerical simulation program is used to calculate wave height, wave pressure, wave velocity parameters and the interaction between waves and vertical rock slopes, and finally obtain specific impact force results.

9. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 1, characterized in that: In step S5, the analysis of the numerical simulation results includes comparing the differences between the standard calculation results and the numerical simulation calculation results, specifically by calculating the impact force results under different working conditions, and analyzing the differences between the impact force results calculated by the two methods, so as to further carry out the analysis.

10. The method for evaluating the impact force of waves on a straight rocky bank slope according to claim 1, characterized in that: In step S6, the evaluation of the impact force of waves on the straight-wall rock slope includes evaluating and analyzing the calculation results of the wave impact force in combination with actual working conditions and the needs of marine engineering construction, and using this as a reference for actual engineering construction.

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