Method for calculating bearing capacity of socketed pile by considering rock breaking

Abstract

The invention discloses a socketed pile bearing capacity calculation method considering rock breaking, and relates to the field of pile foundation bearing capacity analysis. The method comprises the following steps: simplifying a pile-rock contact surface into a concrete-regular triangular rock contact surface, and establishing a concrete-regular triangular rock shear model under a normal stiffness condition; establishing a rock crushing variable evolution equation based on a statistical theory; substituting the rock crushing variable evolution equation into a concrete-regular triangle rock shearing model under a normal stiffness condition, and establishing a concrete-rock shearing model considering rock crushing; based on a socketed pile load transfer mechanism and the concrete-rock shearing model considering rock breaking, a socketed pile load transfer differential equation considering rock breaking is established; and a Runge-Kutta method is adopted to solve the rock-socketed pile load transfer differential equation considering rock breaking, and the bearing capacity of the rock-socketed pile is obtained.

Description

Technical Field

[0001] The invention relates to the field of pile foundation bearing capacity analysis, and in particular to a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into consideration. Background Art

[0002] At present, in the field of civil engineering, especially in foundation engineering, rock-embedded piles are an important structural form, and the calculation of their bearing capacity is crucial to ensure the safety and economy of the project. Rock-embedded piles refer to pile foundations with the pile ends deep in the rock layer, and their bearing capacity mainly depends on the interaction between the pile and the rock. However, as a natural material, the physical and mechanical properties of rock are affected by many factors. Due to my country's vast territory and complex geological terrain, the distribution of rocks in various regions varies greatly. In the southwest region, there is a large range of medium-weathered and relatively broken rock formations. The physical and mechanical properties of these rocks are relatively complex, which brings certain difficulties to the design, construction, management and research of foundations. Due to the distribution of a large number of joints and structural surfaces in the rock-broken area, its physical and mechanical properties are relatively complex, which in turn has a significant impact on the bearing capacity of rock-embedded piles.

[0003] However, there is relatively little research on the physical and mechanical properties of broken rocks in China, and the relevant theories are not yet perfect. Because the physical and mechanical properties of broken rocks are complex and changeable, and are affected by many factors such as geological conditions and environmental factors, the research work faces many challenges. Therefore, the problem of the bearing characteristics of rock-embedded piles in rock crushing areas cannot be effectively solved at present. Summary of the invention

[0004] Based on this, it is necessary to provide a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into account in order to address the above technical issues.

[0005] The present invention adopts the following technical solutions: The present invention provides a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into consideration, comprising: The pile-rock contact surface is simplified to the concrete-regular triangle rock contact surface, and the concrete-regular triangle rock shear model under the condition of constant normal stiffness is established; Through mathematical statistics theory, the rock crushing variable evolution equation is established; Substituting the rock crushing variable evolution equation into the concrete-regular triangle rock shear model under the condition of constant normal stiffness, a concrete-rock shear model of rock crushing is obtained; wherein the rock crushing is caused by the reduction and defects of the effective bearing area of ​​the rock-embedded pile; The load transfer mathematical model of rock-socketed piles is established, and the concrete-rock shear model of rock crushing is substituted into the load transfer mathematical model to obtain the load transfer differential equation of rock-socketed piles considering rock crushing. The load transfer differential equation of rock-socketed piles considering rock crushing is iteratively solved by Runge-Kutta method to obtain the bearing capacity of rock-socketed piles.

[0006] Preferably, the establishment of a concrete-regular triangle rock shear model under a constant normal stiffness condition comprises: In the initial stage of rock-embedded pile loading, the normal stress increment on the pile-rock contact surface is: ; in, E r is the elastic modulus of rock, m is the Poisson's ratio of the rock, r is the radius of the rock-embedded pile, Δ r for radial expansion of rock-embedded piles; Then, the normal stiffness of the pile-rock contact surface is obtained by the ratio of the normal stress increment of the pile-rock contact surface to the radial expansion of the rock-embedded pile: ; in, K is the normal stiffness of the pile-rock contact surface; The normal stress of the pile-rock contact surface is obtained by the sum of the initial normal stress of the pile-rock contact surface and the normal stress increment: ; In the formula, is the normal stress at the pile-rock contact surface, is the initial normal stress at the pile-rock contact surface, is the normal stress increment; Assuming the angle of the regular triangle on the pile-rock contact surface is the dilatancy angle, the radial expansion of the rock-embedded pile can be expressed as: ; in, s is the shear displacement, β is the dilatancy angle; The concrete-regular triangle rock shear model is established as: ; In the formula, is the shear stress of the rock-embedded pile, β is the dilatancy angle, f b is the contact surface friction angle; Substituting the normal stress of the pile-rock contact surface, the radial expansion of the rock-socketed pile, and the normal stress increment into the concrete-regular triangle rock shear model, the shear stress of the rock-socketed pile is obtained as: ; In the formula, K is the normal stiffness of the contact surface,s is the shear displacement, β is the dilatancy angle, f b is the contact surface friction angle; As the load increases, the triangle of the concrete-rock contact surface is destroyed and enters the residual stage. The residual shear stress is: ; in, s r is the residual shear displacement, f r is the residual friction angle.

[0007] Preferably, the step of establishing the rock crushing variable evolution equation comprises: The probability density function of Weibull distribution is used to describe the random behavior of rock crushing. The probability density function of Weibull distribution is: ; in, Q ( F ) is the probability density function of the Weibull distribution, m is the shape parameter, F f is the scale parameter, F is the shear strength of the rock; When the shear strength F Increase to F+ d F When , the average amount of shear stress increment generated by the broken rock unit is: ; in, N s is the average number of rock units per unit area, d N f is the average amount of shear stress increment generated by the crushing of rock units, Q ( F ) is the probability density function of the Weibull distribution; When the shear strength increases from 0 to F, the average number of broken rock units per unit area is: ; Introducing rock crushing variables D : ; in, N s is the average number of rock units per unit area, N f is the average number of broken rock units per unit area; Will N f Substituting into the above formula, the rock crushing variable evolution equation is obtained as follows: .

[0008] Preferably, the concrete-rock shear model of rock crushing is obtained by: Combining the concrete-regular triangle rock shear mathematical model and the rock crushing variable evolution equation, the shear strength equation of the crushed rock unit is obtained as follows: ; ; in, F for Rock shear strength, F f is the proportional parameter of rock shear strength, K is the normal stiffness of the pile-rock contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, f b is the friction angle of the concrete-rock contact surface, β is the shear dilatancy angle of the concrete-rock contact surface; Substituting the shear strength equation of the broken rock unit into the rock crushing variable evolution equation, the rock crushing variable evolution equation described by shear strength is obtained: ; In the formula, D is the rock crushing variable, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, β is the shear dilatancy angle of the concrete-rock interface, m is the shape parameter; According to the balance of forces, the equilibrium relationship of the shear area of ​​the rock unit is obtained as follows: ; in, A s is the total shear area of ​​the concrete-rock interface, A u is the shear area of ​​the unbroken rock unit, A f is the shear area of ​​the crushed rock unit, t is the total shear stress, tu is the shear stress borne by the unbroken rock unit, t f is the shear stress borne by the broken rock unit; After finishing, we can get: ; In the rock shear process, there is a relationship: ; The number of rock units is N s , the number of broken rock units is N f , the number of unbroken rock units is N u , the shear area of ​​each rock unit is A 0; According to the above formula, the shear area of ​​the broken rock unit A u and the total shear area of ​​the concrete-rock interface A s The rock crushing variable described by the rock shear area is obtained as: ; when D = 0, the rock is not broken, and the shear stress of the rock can be expressed as ; when D = 1, the rock is completely broken, and the shear stress of the rock can be expressed as: ; When 0< D When <1, the shear stress of rock can be expressed as: ; Substituting the rock crushing variable evolution equation described by shear strength into the above equation, the concrete-rock shear mathematical model considering rock crushing is obtained as follows: .

[0009] Preferably, the obtaining of the rock-socketed pile load transfer differential equation considering rock crushing comprises: The load transfer differential equation of rock-embedded piles is established as: ; in, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, U is the cross-sectional perimeter of the rock-embedded pile, A ris the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, t p-r is the pile side friction; Substituting the concrete-rock shear mathematical model considering rock crushing into the load transfer differential equation of rock-socketed piles, the load transfer differential equation of rock-socketed piles considering rock crushing is obtained as follows: ; In the formula, U is the cross-sectional perimeter of the rock-embedded pile, A r is the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, β is the shear dilatancy angle of the concrete-rock interface, f b is the contact surface friction angle, f r is the residual friction angle, s f is the shear displacement form of the Weibull distribution scale parameter, m is the shape parameter.

[0010] At least one of the above technical solutions adopted by the present invention can achieve the following beneficial effects: The present invention starts from the perspective of a method for calculating the bearing capacity of rock-socketed piles in a rock-crushed area, establishes a concrete-regular triangle rock shear model, uses Weibull distribution to describe the random behavior of rock crushing and calculates the number of rock crushing units, introduces a rock crushing variable, and obtains a rock crushing variable evolution equation; substitutes the rock crushing variable evolution equation into the concrete-regular triangle rock shear model to obtain a concrete-rock shear model of rock crushing; establishes a load transfer mathematical model of rock-socketed piles, substitutes the concrete-rock shear model of rock crushing to obtain a load transfer differential equation of rock-socketed piles considering rock crushing, and finally iteratively solves the load transfer differential equation of rock-socketed piles considering rock crushing by using the Runge-Kutta method, thereby obtaining the axial force, pile side friction and settlement of the rock-socketed piles to characterize the bearing capacity of the rock-socketed piles.

[0011] In summary, the method for calculating the bearing capacity of rock-embedded piles proposed in the present invention introduces the rock crushing variable evolution equation and the concrete-rock shear model, and takes into account the influence of rock crushing on the concrete-shear mechanism and the rock-embedded pile bearing mechanism. Therefore, the present invention has certain practicality and can well solve the problem of the bearing characteristics of rock-embedded piles in rock crushing areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 A schematic flow chart of a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into consideration provided by the present invention; Figure 2 A concrete-regular triangle rock shear model considering rock crushing for a rock-socketed pile bearing capacity calculation method considering rock crushing provided by the present invention; Figure 3 A method for calculating the bearing capacity of rock-socketed piles considering rock crushing provided by the present invention includes a load transfer mechanism of rock-socketed piles considering rock crushing; Figure 4 The on-site geological conditions for the rock-embedded pile bearing capacity calculation method considering rock crushing provided by the present invention; Figure 5 A comparison chart of results of a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into consideration provided by the present invention. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0014] The technical solutions provided by various embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0015] Figure 1 The present embodiment provides a flow chart of a method for calculating the bearing capacity of rock-embedded piles taking rock crushing into consideration, comprising the following steps: S101: Simplify the pile-rock contact surface into a concrete-regular triangular rock contact surface, and establish a concrete-regular triangular rock shear mathematical model under constant normal stiffness conditions, see Figure 2 , including: In the initial stage of rock-embedded pile loading, the normal stress increment on the pile-rock contact surface is: ; in, E r is the elastic modulus of rock, m is the Poisson's ratio of the rock, ris the radius of the rock-embedded pile, Δ r for radial expansion of rock-embedded piles; Then, the normal stiffness of the pile-rock contact surface is obtained by the ratio of the normal stress increment of the pile-rock contact surface to the radial expansion of the rock-embedded pile: ; in, K is the normal stiffness of the pile-rock contact surface; The normal stress of the pile-rock contact surface is obtained by the sum of the initial normal stress of the pile-rock contact surface and the normal stress increment: ; In the formula, is the normal stress at the pile-rock contact surface, is the initial normal stress at the pile-rock contact surface, is the normal stress increment; Assuming the angle of the regular triangle on the pile-rock contact surface is the dilatancy angle, the radial expansion of the rock-embedded pile can be expressed as: ; in, s is the shear displacement, β is the dilatancy angle; The concrete-regular triangle rock shear model is established as: ; In the formula, is the shear stress of the rock-embedded pile, β is the dilatancy angle, f b is the contact surface friction angle; Substituting the normal stress of the pile-rock contact surface, the radial expansion of the rock-socketed pile, and the normal stress increment into the concrete-regular triangle rock shear model, the shear stress of the rock-socketed pile is obtained as: ; In the formula, K is the normal stiffness of the contact surface, s is the shear displacement, β is the dilatancy angle, f b is the contact surface friction angle; As the load increases, the triangle of the concrete-rock contact surface is destroyed and enters the residual stage. The residual shear stress is: ; in, s r is the residual shear displacement, f r is the residual friction angle.

[0016] S102: Establish rock crushing variable evolution equation through mathematical statistical theory, including: The probability density function of Weibull distribution is used to describe the random behavior of rock crushing. The probability density function of Weibull distribution is: ; in, Q ( F ) is the probability density function of the Weibull distribution, m is the shape parameter, F f is the scale parameter, F is the shear strength of the rock; When the shear strength F Increase to F+ d F When , the average amount of shear stress increment generated by the broken rock unit is: ; in, N s is the average number of rock units per unit area, d N f is the average amount of shear stress increment generated by the crushing of rock units, Q ( F ) is the probability density function of the Weibull distribution; When the shear strength increases from 0 to F When , the average number of broken rock units per unit area is: ; Introducing rock crushing variables D : ; in, N s is the average number of rock units per unit area, N f is the average number of broken rock units per unit area; Will N f Substituting into the above formula, the rock crushing variable evolution equation is obtained as follows: .

[0017] S103: Substitute the rock crushing variable evolution equation into the concrete-regular triangle rock shear model under the condition of constant normal stiffness, and obtain the concrete-rock shear model of rock crushing by deduction; specifically including: Combining the concrete-regular triangle rock shear mathematical model and the rock crushing variable evolution equation, the shear strength equation of the crushed rock unit is obtained as follows: ; ; In the formula, F for Rock shear strength, F f is the proportional parameter of rock shear strength, K is the normal stiffness of the pile-rock contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, f b is the friction angle of the concrete-rock contact surface, β is the shear dilatancy angle of the concrete-rock contact surface; Substituting the shear strength equation of the broken rock unit into the rock crushing variable evolution equation, the rock crushing variable evolution equation described by shear strength is obtained: ; In the formula, D is the rock crushing variable, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, β is the shear dilatancy angle of the concrete-rock interface, m is the shape parameter; According to the balance of forces, the equilibrium relationship of the shear area of ​​the rock unit is obtained as follows: ; in, A s is the total shear area of ​​the concrete-rock interface, A u is the shear area of ​​the unbroken rock unit, A f is the shear area of ​​the crushed rock unit, t is the total shear stress, t u is the shear stress borne by the unbroken rock unit, t f is the shear stress borne by the broken rock unit; After finishing, we can get: ; During the rock shearing process, the relationship exists: ; The number of rock units isN s , the number of broken rock units is N f , the number of unbroken rock units is N u , the shear area of ​​each rock unit is A 0; According to the above formula, the shear area of ​​the broken rock unit A u and the total shear area of ​​the concrete-rock interface A s The rock crushing variable described by the rock shear area is obtained as: ; when D = 0, the rock is not broken, and the shear stress of the rock can be expressed as ; when D = 1, the rock is completely broken, and the shear stress of the rock can be expressed as: ; When 0< D When <1, the shear stress of rock can be expressed as: ; Substituting the rock crushing variable evolution equation described by shear strength into the above equation, the concrete-rock shear mathematical model considering rock crushing is obtained as follows: .

[0018] S104: Establish a load transfer mathematical model for rock-embedded piles, and substitute the concrete-rock shear model of rock crushing into the load transfer mathematical model to obtain a load transfer differential equation for rock-embedded piles considering rock crushing, which specifically includes: For the load transfer mechanism of rock-socketed piles considering rock crushing, see Figure 3 ; The load transfer differential equation of rock-embedded piles is established as: ; in, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, U is the cross-sectional perimeter of the rock-embedded pile, A r is the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, t p-r is the pile side friction; Substituting the concrete-rock shear mathematical model considering rock crushing into the load transfer differential equation of rock-socketed piles, the load transfer differential equation of rock-socketed piles considering rock crushing is obtained as follows: ; In the formula, U is the cross-sectional perimeter of the rock-embedded pile, A r is the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, β is the shear dilatancy angle of the concrete-rock interface, f b is the contact surface friction angle, f r is the residual friction angle, s f is the shear displacement form of the Weibull distribution scale parameter, m is the shape parameter.

[0019] The rock crushing is caused by the reduction and defects of the effective bearing area.

[0020] S105: The load transfer differential equation of rock-socketed piles considering rock crushing is iteratively solved by Runge-Kutta method to obtain the bearing capacity of rock-socketed piles, which includes: A nonlinear second-order differential equation is established and solved using Runge-Kutta. The nonlinear second-order differential equation is: ; The boundary conditions of the nonlinear second-order differential equation are: ;

[0021] In the formula, z 0 is the vertical coordinate of the pile top, s t is the settlement of the pile top, P t is the pile top load.

[0022] Introduce new variables: ; Find the first-order derivative of the formula: ; Substituting the formula into the formula, we can get: ; The formula is a set of first-order differential equations, and the boundary conditions are modified as follows: ; Combining the two methods, we can get: ; The above-mentioned solution process can be solved by compiling a computer program.

[0023] This example uses a rock-embedded pile project in a rock-broken area. The pile is 36.5 m long and 2.5 m in diameter. The on-site geological conditions refer to Figure 4 , rock formation mechanical parameters are shown in the following table:

[0024] Substitute the above parameters into the model for calculation, and the results are shown in Figure 5 The calculation results of this method are in good agreement with the on-site monitoring results, which shows that the calculation method for the bearing capacity of rock-embedded piles considering rock crushing proposed in this invention is correct and reasonable.

[0025] In summary, through the verification of this embodiment, it is explained that the method for calculating the bearing capacity of rock-embedded piles proposed in the invention takes into account the influence of rock crushing on the concrete-shear mechanism and the bearing mechanism of rock-embedded piles by introducing the rock crushing variable evolution equation and the concrete-rock shear model. Therefore, the present invention has certain practicality and can well solve the problem of the bearing characteristics of rock-embedded piles in rock crushing areas.

[0026] Obviously, the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A method for calculating the bearing capacity of rock-embedded piles considering rock crushing, characterized in that: The method comprises the following steps: The pile-rock contact surface is simplified to the concrete-regular triangle rock contact surface, and the concrete-regular triangle rock shear model under the condition of constant normal stiffness is established; Through mathematical statistics theory, the rock crushing variable evolution equation is established; Substituting the rock crushing variable evolution equation into the concrete-regular triangle rock shear model under the condition of constant normal stiffness, a concrete-rock shear model of rock crushing is obtained; wherein the rock crushing is caused by the reduction and defects of the effective bearing area of ​​the rock-embedded pile; The load transfer mathematical model of rock-socketed piles is established, and the concrete-rock shear model of rock crushing is substituted into the load transfer mathematical model to obtain the load transfer differential equation of rock-socketed piles considering rock crushing. The load transfer differential equation of rock-socketed piles considering rock crushing is iteratively solved by Runge-Kutta method to obtain the bearing capacity of rock-socketed piles.

2. A method for calculating the bearing capacity of rock-socketed piles taking rock crushing into consideration as claimed in claim 1, characterized in that: The method of establishing a concrete-regular triangle rock shear model under a constant normal stiffness condition includes: In the initial stage of rock-embedded pile loading, the normal stress increment on the pile-rock contact surface is: ； in, E r is the elastic modulus of rock, μ is the Poisson's ratio of the rock, r is the radius of the rock-embedded pile, Δ r for radial expansion of rock-embedded piles; Then, the normal stiffness of the pile-rock contact surface is obtained by the ratio of the normal stress increment of the pile-rock contact surface to the radial expansion of the rock-embedded pile: ； in, K is the normal stiffness of the pile-rock contact surface; The normal stress of the pile-rock contact surface is obtained by the sum of the initial normal stress of the pile-rock contact surface and the normal stress increment: ； In the formula, is the normal stress at the pile-rock contact surface, is the initial normal stress at the pile-rock contact surface, is the normal stress increment; Assuming the angle of the regular triangle on the pile-rock contact surface is the dilatancy angle, the radial expansion of the rock-embedded pile can be expressed as: ； in, s is the shear displacement, β is the dilatancy angle; The concrete-regular triangle rock shear model is established as: ； In the formula, is the shear stress of the rock-embedded pile, β is the dilatancy angle, φ b is the contact surface friction angle; Substituting the normal stress of the pile-rock contact surface, the radial expansion of the rock-socketed pile, and the normal stress increment into the concrete-regular triangle rock shear model, the shear stress of the rock-socketed pile is obtained as: ； In the formula, K is the normal stiffness of the contact surface, s is the shear displacement, β is the dilatancy angle, φ b is the contact surface friction angle; As the load increases, the triangle of the concrete-rock contact surface is destroyed and enters the residual stage. The residual shear stress is: ； in, s r is the residual shear displacement, φ r is the residual friction angle.

3. A method for calculating the bearing capacity of rock-socketed piles taking rock crushing into consideration as claimed in claim 1, characterized in that: The establishment of the rock crushing variable evolution equation includes: The probability density function of Weibull distribution is used to describe the random behavior of rock crushing. The probability density function of Weibull distribution is: ； in, Q ( F ) is the probability density function of the Weibull distribution, m is the shape parameter, F f is the scale parameter, F is the shear strength of the rock; When the shear strength F Increase to F+dF When , the average amount of shear stress increment generated by the broken rock unit is: ； in, N s is the average number of rock units per unit area, d N f is the average amount of shear stress increment generated by the crushing of rock units, Q ( F ) is the probability density function of the Weibull distribution; When the shear strength increases from 0 to F When , the average number of broken rock units per unit area is: ； Introducing rock crushing variables D : ； in, N s is the average number of rock units per unit area, N f is the average number of broken rock units per unit area; Will N f Substituting into the above formula, the rock crushing variable evolution equation is obtained as follows: 。 4. A method for calculating the bearing capacity of rock-socketed piles taking rock crushing into consideration as claimed in claim 1, characterized in that: The concrete-rock shear model of rock crushing is obtained by: Combining the concrete-regular triangle rock shear mathematical model and the rock crushing variable evolution equation, the shear strength equation of the crushed rock unit is obtained as follows: ； ； In the formula, F is the shear strength of rock, F f is the proportional parameter of rock shear strength, K is the normal stiffness of the pile-rock contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, φ b is the friction angle of the concrete-rock contact surface, β is the shear dilatancy angle of the concrete-rock contact surface; Substituting the shear strength equation of the broken rock unit into the rock crushing variable evolution equation, the rock crushing variable evolution equation described by shear strength is obtained: ； In the formula, D is the rock crushing variable, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, s is the shear displacement, s f is the shear displacement form of the Weibull distribution scale parameter, β is the shear dilatancy angle of the concrete-rock interface, m is the shape parameter; According to the balance of forces, the equilibrium relationship of the shear area of ​​the rock unit is obtained as follows: ； in, A s is the total shear area of ​​the concrete-rock interface, A u is the shear area of ​​the unbroken rock unit, A f is the shear area of ​​the crushed rock unit, τ is the total shear stress, τ u is the shear stress borne by the unbroken rock unit, τ f is the shear stress borne by the broken rock unit; After finishing, we can get: ； In the rock shear process, there is a relationship: ； The number of rock units is N s , the number of broken rock units is N f , the number of unbroken rock units is N u , the shear area of ​​each rock unit is A 0; According to the above formula, the shear area of ​​the broken rock unit A u and the total shear area of ​​the concrete-rock interface A s The rock crushing variable described by the rock shear area is obtained as: ； when D = 0, the rock is not broken, and the shear stress of the rock can be expressed as ； when D = 1, the rock is completely broken, and the shear stress of the rock can be expressed as: ； When 0 < D < 1, the shear stress of rock can be expressed as: ； Substituting the rock crushing variable evolution equation described by shear strength into the above equation, the concrete-rock shear mathematical model considering rock crushing is obtained as follows: 。 5. A method for calculating the bearing capacity of rock-socketed piles taking rock crushing into consideration as claimed in claim 1, characterized in that: The acquisition of the rock-embedded pile load transfer differential equation considering rock crushing includes: The load transfer differential equation of rock-embedded piles is established as: ； in, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, U is the cross-sectional perimeter of the rock-embedded pile, A r is the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, τ p-r is the pile side friction; Substituting the concrete-rock shear mathematical model considering rock crushing into the load transfer differential equation of rock-socketed piles, the load transfer differential equation of rock-socketed piles considering rock crushing is obtained as follows: ； In the formula, U is the cross-sectional perimeter of the rock-embedded pile, A r is the cross-sectional area of ​​the rock-embedded pile, E c is the elastic modulus of concrete, s is the shear displacement, z is the vertical coordinate of the rock-embedded pile, is the initial normal stress at the pile-rock contact surface, K is the normal stiffness of the contact surface, β is the shear dilatancy angle of the concrete-rock interface, φ b is the contact surface friction angle, φ r is the residual friction angle, s f is the shear displacement form of the Weibull distribution scale parameter, m is the shape parameter.

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