CN-121980844-A - Roadway anchor rod group support parameter intelligent optimization method based on unbalanced force

CN121980844ACN 121980844 ACN121980844 ACN 121980844ACN-121980844-A

Abstract

The invention relates to the technical field of mining engineering and geotechnical engineering support design, and discloses an intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force, which constructs a surrounding rock finite element model, and calculating a plastic stress increment by utilizing a minimum plastic residual energy principle, mapping the plastic stress increment into a node unbalanced force vector, and constructing an unbalanced force field reflecting the reinforcement requirement, thereby generating an initial scheme. And then, introducing a virtual anchor rod unit to establish a nonlinear coupling model, solving an incremental balance equation and judging whether the unbalanced force is smaller than a threshold value. If the parameter is smaller than the threshold value, outputting the optimal parameter, otherwise, constructing a comprehensive objective function containing safety and economy, searching and decoding by using a particle swarm algorithm to obtain a new parameter, and re-entering a virtual anchor rod unit to calculate to form a closed loop until convergence. According to the invention, intelligent optimization is driven by a physical mechanism, so that the problem that the traditional design lacks mechanical basis is solved, and the accurate optimization of the support parameters is realized.

Inventors

WANG SHOUGUANG
GAO FUQIANG
KANG HONGPU
LU ZHIGUO
WANG WANJIE

Assignees

中煤科工开采研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20251218

Claims (10)

1. An intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force is characterized by comprising the following steps: S10, building an initial finite element model of surrounding rock, building a geometric entity based on geological data, performing grid discretization, defining material parameters and yield criteria, assembling a global stiffness matrix, and applying a displacement boundary and an initial ground stress field to form a mechanical system to be analyzed; S20, performing unbalanced force field diagnosis, namely simulating excavation unloading by utilizing the mechanical system to be analyzed, solving a real stress state of a super-yield unit according to a minimum plastic residual energy principle, calculating a plastic stress increment, mapping the plastic stress increment into a node unbalanced force vector through unit integral, and constructing an unbalanced force field reflecting local damage and reinforcement requirements; s30, generating an initial scheme, extracting node distribution characteristics according to the unbalanced force field, analyzing regional reinforcement requirements, and determining the length, the spacing and the angle of the anchor rods to obtain an initial support parameter set; S40, establishing a coupling analysis model, taking an anchor rod as a virtual unit, introducing a bonding slip constitutive relation describing nonlinear shearing behaviors of an anchor rod-surrounding rock interface, deducing a contact stiffness matrix and superposing the contact stiffness matrix to the global stiffness matrix, constructing an incremental balance equation set representing a cooperative deformation mechanism, solving the equation set to obtain the supporting effect of the supporting scheme on the surrounding rock, judging whether the unbalanced force of the surrounding rock is smaller than a given threshold value, outputting the current supporting scheme as an optimal supporting parameter if the unbalanced force is smaller than the given threshold value, otherwise, executing the following steps S50, constructing a comprehensive objective function, namely selecting residual unbalanced force norms, characteristic point displacements, anchor rod axial force and material cost, and constructing a comprehensive fitness function through normalization and weighted summation; S60, performing global optimization, namely encoding supporting parameters, initializing a particle population by using the initial supporting parameter set, driving particles to search iteratively in a multidimensional space based on the incremental balance equation set and the comprehensive fitness function, and using boundary mechanism constraint to obtain new supporting parameters, re-entering a virtual anchor rod unit to calculate and circularly solve unbalanced force, and stopping optimizing until the unbalanced force is smaller than a given value to give optimal particles; And S70, outputting optimal parameters, extracting position vectors corresponding to the global optimal particles, decoding the position vectors into specific numerical values, and outputting the specific numerical values as a final scheme after verification.
2. The intelligent optimization method for roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein the step S10 specifically comprises the following steps: constructing a three-dimensional geometric entity according to the geological data, dividing the three-dimensional geometric entity by adopting eight-node hexahedral units in a roadway peripheral stress concentration area, and discretizing the three-dimensional geometric entity into a grid model consisting of nodes and units; the method specifically comprises the steps of integrating strain energy in each unit volume based on a virtual work principle to obtain a unit stiffness matrix, and assembling the unit stiffness matrix into the global stiffness matrix of the mechanical system to be analyzed according to a node topological relation.
3. The intelligent optimization method of roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein in S20, the step of solving the real stress state of the super-yielding unit according to the minimum plastic residual energy principle, and calculating the plastic stress increment specifically comprises the following steps: Assuming elasticity heuristic stress of the material retention line elasticity calculation unit; Aiming at an integral point which is judged to be yielding by the elastic heuristic stress, searching a real stress tensor on a yielding surface, so that the plastic complementary energy increment between the real stress tensor and the elastic heuristic stress is minimum; And calculating the difference between the elastic trial stress and the real stress tensor to obtain a plastic stress difference tensor as the plastic stress increment.
4. The intelligent optimization method for roadway anchor rod group support parameters based on unbalanced forces according to claim 3, wherein in the step S20, the unbalanced force field step of constructing the unbalanced force field reflecting the local damage and reinforcement requirements by mapping the unit integral to a node unbalanced force vector comprises the following steps: based on the virtual work principle, the plastic stress difference tensor integral inside the unit is transformed into a unit node unbalanced force vector; assembling and superposing the unbalanced force vectors of the unit nodes of all units according to node numbers to form the unbalanced force field; the unbalanced force field quantitatively indicates the size of a gap of the surrounding rock self-supporting force and the direction of the required external supporting force.
5. The intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force according to claim 4, wherein in the step S30, the step of determining the anchor rod length according to the node distribution characteristics extracted by the unbalanced force field specifically comprises the following steps: searching node unbalanced force vector distribution along the radial direction in the area to be supported, and recording unbalanced force modulus along the depth of surrounding rock; And finding a minimum depth value of the unbalanced force modulus meeting the attenuation coefficient requirement, and determining the length of the anchor rod by taking the minimum depth value as a basis.
6. The intelligent optimization method of roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein in S30, the analyzing the regional reinforcement requirement, determining the anchor rod spacing and angle specifically comprises: Calculating resultant force vectors of all the node unbalanced force vectors in the area to be supported, and calculating projection of the resultant force vectors on the normal direction of the roadway surface to obtain area normal reinforcement total demand force; establishing total anchor rod number requirements according to the ratio of the area normal reinforcement total demand force to the limit bearing capacity of a single anchor rod, and reversely pushing to obtain the anchor rod spacing; And determining the initial installation angle of the anchor rod according to the opposite direction of the local resultant force vector.
7. The intelligent optimization method for roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein in the step S40, anchor rods are used as virtual units, and a double-index bonding sliding constitutive model is adopted as the bonding sliding constitutive relation: the double-index bond slip constitutive model comprises a bond strength function describing a softening stage; the deriving of the contact stiffness matrix comprises the steps of deriving the interface relative slip in the double-index bonding slip constitutive model to obtain interface tangent stiffness, and assembling the contact stiffness matrix based on the interface tangent stiffness.
8. The intelligent optimization method of roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein in S50, the step of establishing a comprehensive fitness function specifically includes: Respectively calculating the residual unbalanced force norm, the characteristic point displacement, the normalized maximum displacement of the anchor rod shaft force and the material cost, the normalized maximum unbalanced force, the normalized anchor rod shaft force and the normalized material cost as four normalization indexes; and combining the four normalization indexes in a weighted summation mode to form the comprehensive fitness function for directly reflecting the tradeoff among safety, stability and economy of the scheme.
9. The intelligent optimization method of roadway anchor rod group support parameters based on unbalanced forces of claim 1, wherein in the step S60, the specific strategy of restraining the variable range by using the boundary mechanism is as follows: When the particle updating position exceeds a preset range for acquiring new supporting parameters, the particle updating position is forcedly corrected; If the particle update position is less than a lower bound, setting the particle update position to the lower bound and setting a particle velocity to zero; If the particle update position is greater than an upper bound, the particle update position is set to the upper bound and the particle velocity is set to zero.
10. The intelligent optimization method for roadway anchor rod group support parameters based on unbalanced forces according to claim 1, wherein the step S70 specifically comprises: extracting a position vector corresponding to the global optimal particle, and decoding the position vector into a specific parameter conforming to an engineering modulus through a nearest neighbor mapping and directional rounding strategy; checking the decoded specific parameters by using an intensity folding and subtracting method and calculating a system safety coefficient; and generating a report comprising a three-dimensional topological model and a bill of materials as a final scheme to be output after verifying based on the system safety coefficient.

Description

Roadway anchor rod group support parameter intelligent optimization method based on unbalanced force Technical Field The invention relates to the technical field of mining engineering and geotechnical engineering support design, in particular to an intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force. Background After the deep mine tunnel is excavated, the stress redistribution of surrounding rock can cause the surrounding rock to generate large deformation or even damage, and the active support by adopting the anchor rod group is a main means for controlling the stability of the surrounding rock. In the existing support design system, engineering analogy and aided design based on traditional numerical simulation are mainstream modes. Engineering technicians usually perform qualitative analysis according to the stress cloud chart, the displacement cloud chart or the plastic region distribution range which are output by numerical calculation, and estimate the length, the spacing and the installation angle of the anchor rod by virtue of engineering experience. The design mode lacks definite quantitative mechanical index guidance, and cannot accurately quantify self-bearing gaps and required external compensation force of surrounding rock at a specific position, so that the selection of supporting parameters is often provided with large blindness, and potential safety hazards caused by insufficient supporting strength or resource waste caused by excessive supporting are easily caused. In addition, when performing numerical analysis of an anchor bolt support system, accurately simulating the interaction mechanism between an anchor bolt and surrounding rock is a key to evaluating the support effect. Existing conventional analytical models often simplify the anchoring interface, for example, assuming bolt to surrounding rock node displacement coordination (perfect bonding) or simulating contact with only a simple linear spring unit. However, in practical engineering, the anchoring interface has nonlinear mechanical behavior including bond slip, debonding softening and friction effect. The simplification processing ignores the release effect of interface sliding on surrounding rock deformation, so that the calculated surrounding rock deformation and the stress state of the anchor rod deviate from the actual situation, and the guiding value of the numerical simulation result on engineering design is reduced. In the scheme optimization level, the current support parameter determination process mainly depends on a manual trial and error method, namely, a designer manually adjusts parameters, operates a model and checks results. Because roadway support relates to a plurality of parameters such as anchor rod length, spacing, pretightening force and angle, complex nonlinear coupling relations exist among the parameters, manual trial and error is difficult to traverse all existing parameter combinations, and a real global optimal solution cannot be found in a multidimensional parameter space. Meanwhile, the existing design process is usually focused on meeting the single safety and stability requirement, lacks an effective means for taking engineering cost as a core variable into a mathematical model to synchronously optimize, and is difficult to realize the accurate balance of safety indexes and economic indexes in the design stage. Disclosure of Invention Aiming at the defects of the prior art, the invention provides an intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force, which solves the problems that the existing roadway support design lacks quantitative mechanical basis for parameter selection, calculation deviation is caused by anchoring interface simulation simplification, and safety and economical global collaborative optimization are difficult to realize depending on manual trial and error. In order to achieve the above purpose, the invention provides an intelligent optimization method for roadway anchor rod group support parameters based on unbalanced force, which comprises the following steps: And constructing an initial finite element model of the surrounding rock. And establishing a geometric entity based on geological data, performing grid discretization, and dividing the three-dimensional geometric entity by adopting eight-node hexahedral units in a roadway peripheral stress concentration area to form a grid model consisting of nodes and units. Defining surrounding rock material parameters and yield criteria, calculating the stiffness matrix of each unit based on virtual work principle integration, assembling according to node topological relation to generate a global stiffness matrix of the mechanical system to be analyzed, and applying a displacement boundary and an initial ground stress field. An imbalance force field diagnosis is performed. And simulating excavation unloading by using a mechanical