A simulated method of preparing a delaminated packed compact

Abstract

The present application relates to the technical field of geotechnical engineering and mine engineering, and particularly relates to a simulation preparation method of a separation layer filling compaction body, which comprises the following steps: implementing simulation mining in a similar material model to form a separation layer space at a target layer; not injecting grout after the separation layer is formed, applying short-time enhanced disturbance to the separation layer, and determining whether the separation layer is a lockable separation layer according to the regression condition of the geometric shape of the separation layer after the disturbance; after the separation layer is determined to be a lockable separation layer, injecting filling slurry into the separation layer space while keeping the external boundary condition unchanged; during the grouting process, determining that the slurry enters a structure transition stage according to the characteristics of the change from flow-dominated deformation to load-bearing-dominated deformation, and actively changing the loading mode only in this stage to cause a mutation of the loading path; applying a disturbance loading with a controlled amplitude in the later stage of slurry consolidation, and determining that the filling compaction body is formed according to whether the filling body response appears an irreversible change after the disturbance.

Description

Technical Field

[0001] This invention relates to the fields of geotechnical engineering and mining engineering, and in particular to a method for simulating the preparation of delamination filling compacted bodies. Background Technology

[0002] In mining and related rock mechanics research, similar material models are often used to simulate the deformation and evolution of rock structures under mining conditions. Grouting and filling the delamination space formed after mining is an important means of studying the control of overburden movement and the load-bearing behavior of the filling body. Existing simulation methods usually inject filling grout into the delamination space after the delamination is formed, and simulate the consolidation and load-bearing process of the grout under overburden pressure by applying constant loading, graded loading, or loading according to a predetermined program, so as to obtain the mechanical response characteristics of the filling body under different loading conditions.

[0003] In existing technologies, the loading method is usually relatively independent of the grouting and consolidation process. The loading path is mostly carried out continuously according to a preset program, failing to distinguish the differences in the different structural evolution stages of the grout during the preparation process. Especially in the critical stage when the grout changes from a flow-dominated state to a load-bearing-dominated state, the loading method still remains continuous or changes steadily, resulting in a lack of targeted matching control between the loading path and the grout forming stage, making it difficult to effectively control the formation process of the filling compaction body. Summary of the Invention

[0004] To overcome the above deficiencies, this invention provides a method for simulating the preparation of delamination filling compacted bodies, aiming to improve the problem of lack of targeted matching control between the loading path and the slurry forming stage, which makes it difficult to effectively regulate the formation process of filling compacted bodies.

[0005] This invention provides the following technical solution: a method for simulating the preparation of a delaminated filled compacted entity, comprising the following steps:

[0006] S1. Simulate mining in a similar material model to cause relative displacement of the rock strata above and below the target stratum, forming a separation space at the target stratum;

[0007] S2. After the delamination is formed, grouting is not performed. A short-term enhanced disturbance is applied to the delamination. If the geometry of the delamination can return to the state before the disturbance after the disturbance ends and does not continue to expand or close, the delamination is determined to be a lockable delamination. Otherwise, the disturbance is repeated until the determination condition is met.

[0008] S3. After the delamination is determined to be lockable, filler grout is injected into the delamination space while keeping the external boundary conditions unchanged.

[0009] S4. During the grouting process, when the fluidity of the grout decreases significantly and its response to loading changes from flow-dominated to load-dominated, the grout is determined to have entered the structural transition stage.

[0010] S5. Actively change the loading method during the structural transition stage to cause a sudden change in the loading path, and restore stable loading after the structural transition stage ends, so that the slurry continues to consolidate and be compacted in the delamination space.

[0011] S6. Apply a controlled disturbance load in the later stage of slurry consolidation. If the response path, stiffness, or deformation characteristics of the filling body change irreversibly when the loading is restored after the disturbance, the filling compaction body is determined to be formed.

[0012] By adopting the above technical solution, the identification of the slurry structure evolution stage and the phased control of the loading path are realized in the simulated preparation of the delamination filling compaction entity. This enables the loading method to be adjusted in a targeted manner at the critical stage when the slurry changes from a flow-dominated state to a load-bearing-dominated state. This solves the problem in the prior art where the loading path is continuously carried out according to a preset program, which is difficult to match with the slurry forming stage, resulting in a lack of effective control in the formation process of the filling compaction entity.

[0013] Preferably, in step S1, the step of implementing simulated sampling in a similar material model includes:

[0014] Similar materials in the target layer are gradually removed or equivalently extracted;

[0015] As the removal or equivalent extraction proceeds, the similar material layers above and below the target layer undergo relative displacement.

[0016] When relative displacement causes a gap to form between similar material layers above and below the target layer, a delamination space is formed at the target layer.

[0017] Preferably, in step S2, the step of applying a short-time enhancement perturbation to the delamination includes:

[0018] After the simulated mining is completed and the delamination is formed, and before the filling slurry is injected into the delamination space, a short-term enhanced disturbance is applied to the delamination.

[0019] The short-term enhanced disturbance is an enhanced disturbance relative to the disturbance intensity applied during the simulated mining process, so that the delamination produces a larger response in a short period of time than at the end of the mining phase.

[0020] Preferably, in step S2, the step of determining that the delamination is a lockable delamination if the geometry of the delamination can return to the state before the disturbance and does not continue to expand or close after the disturbance ends includes:

[0021] After the short-term enhanced disturbance ends, the observation phase of the delamination state begins;

[0022] During the observation phase of the delamination state, it is determined whether the geometric morphology of the delamination continues to evolve over time;

[0023] When the geometry of the delamination no longer expands or closes during the observation phase and can return to the state before the disturbance, the delamination is determined to be a lockable delamination.

[0024] Preferably, in step S2, the step of determining whether the delamination geometry has reverted includes:

[0025] Determine the thickness variation and spatial distribution range of the delamination;

[0026] When the thickness and spatial distribution of the delamination return to the pre-disturbance state after the short-term enhanced disturbance ends, and no longer change continuously over time during the observation period, it is determined that the geometry of the delamination can return to the pre-disturbance state.

[0027] Preferably, in step S3, the step of injecting filling slurry into the delamination space while keeping the external boundary conditions unchanged includes:

[0028] After the delamination is determined to be a lockable delamination, the loading conditions at the end of the simulated mining remain unchanged;

[0029] With the loading conditions remaining unchanged, filling grout is injected into the delamination space so that the grouting process is carried out under the same stress state as the delamination locking stage.

[0030] Preferably, in step S4, the step of determining whether the slurry has entered the structural transition stage includes:

[0031] During the process of injecting filling grout into the delamination space, the state of the grout is continuously observed;

[0032] When the deformation response of the grout gradually changes from being dominated by flow deformation to being dominated by load-bearing deformation during a continuous grouting period, and this change remains stable during subsequent grouting processes, the grout is determined to have entered the structural transition stage.

[0033] Preferably, in step S5, the step of causing a sudden change in the loading path includes:

[0034] After determining that the slurry has entered the structural transition stage, loading will not continue along the original loading path for the time being.

[0035] While keeping other preparation conditions unchanged, a loading change different from the original loading path is applied during the structural transition stage, causing the loading mode to change discontinuously in a short time.

[0036] After the discontinuous change is completed, the abrupt loading is terminated, and the system is restored to the stable loading mode before the structural transition stage.

[0037] Preferably, in step S5, the step of restoring stable loading after the structural transition phase ends includes:

[0038] After the loading path abrupt change is completed, the state of the slurry is further assessed.

[0039] When the response of the slurry to changes in loading no longer changes significantly, and its load-bearing deformation characteristics remain stable during subsequent loading, the structural transition stage is considered to have ended.

[0040] After the structural transition phase is completed, the system is restored to a stable loading state, allowing the slurry to continue to solidify and compact within the delamination space.

[0041] Preferably, in step S6, the step of determining that the filling compaction body is formed if the response path, stiffness, or deformation characteristics of the filling body undergo an irreversible change when the loading is restored after the disturbance includes:

[0042] In the later stage of slurry consolidation, while keeping other preparation conditions unchanged, a disturbance loading with controlled amplitude is applied to the formed filling body;

[0043] After the disturbance loading ends, the loading state is restored to that before the disturbance, and the response behavior of the filling body during the restoration loading process is compared and judged.

[0044] When the response behavior after reloading shows a persistent trend of change relative to the state before the disturbance, and this trend does not regress during subsequent loading processes, the filling pressure entity is determined to be formed successfully.

[0045] The present invention has the following beneficial effects:

[0046] 1. In this invention, by actively implementing abrupt changes in the stress loading path during the transition stage of the slurry structure, the matching control of the loading method with the key structural evolution stage of the slurry's transformation from flow-dominated to load-bearing-dominated is achieved, solving the problem of the loading path being disconnected from the slurry forming stage and the forming process being difficult to control in existing simulation preparation methods.

[0047] 2. In this invention, by introducing anti-stability induction after the formation of the delamination and combining it with the geometric morphology regression after the disturbance to make a lockable determination, the screening of whether the delamination is suitable for controlled filling is realized, which solves the problem in the existing methods that rely solely on experience to wait for the delamination to stabilize and are difficult to distinguish between true stability and transient stability.

[0048] 3. In this invention, by applying a controlled amplitude disturbance load in the later stage of slurry consolidation and judging based on the irreversible change of response characteristics when the load is restored after the disturbance, the structural confirmation of the completed state of the filling compaction is realized, which solves the problem that the determination of the completion of the molding depends on the time setting or a single parameter threshold in the existing methods.

[0049] 4. In this invention, by delaying the release of non-target bearing constraints during the loading process of the filling body and releasing them instantaneously when approaching the limit state, the bearing and failure behavior of the filling press body is identified, which solves the problem that the behavior of the body is masked and difficult to analyze separately due to the superposition of multiple bearing paths in the existing methods. Attached Figure Description

[0050] Figure 1 This is a flowchart of a simulated preparation method for a delaminated filled compacted solid proposed in this invention. Detailed Implementation

[0051] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] In a first embodiment of the present invention, the present invention provides a method for simulating the preparation of a delaminated filled compacted entity, such as... Figure 1 As shown, it includes the following steps:

[0053] S1. Simulate mining in a similar material model to cause relative displacement of the rock strata above and below the target stratum, forming a separation space in the target stratum.

[0054] Furthermore, in step S1, the step of implementing simulated sampling in a similar material model includes:

[0055] Similar materials in the target layer are gradually removed or equivalently extracted;

[0056] As the removal or equivalent extraction proceeds, the similar material layers above and below the target layer undergo relative displacement.

[0057] When relative displacement causes a gap to form between similar material layers above and below the target layer, a delamination space is formed at the target layer.

[0058] Specifically, by implementing simulated mining operations in a similar material model, the structural response process of the target stratum under mining conditions is reproduced, and a separation space is formed in the target stratum for subsequent filling simulation.

[0059] Similar material models are used to simulate actual geological structures. Their internal structure is constructed according to geometric similarity ratio, density similarity ratio and mechanical similarity relationship. The target layer corresponds to the location of rock strata that may delaminate in actual engineering.

[0060] During the simulated mining process, similar materials in the target stratum are gradually removed or equivalently extracted to simulate the gradual weakening of the bearing capacity of the target stratum during actual mining.

[0061] Gradual removal refers to removing similar materials in the target layer in stages according to the predetermined mining direction and pace, so that the supporting effect of the target layer on the overlying similar material layer is gradually reduced.

[0062] Equivalent removal is an optional approach that achieves the same mechanical effect as physical removal by reducing the equivalent elastic modulus or equivalent bearing parameters of similar materials in the target layer.

[0063] As the process of gradual removal or equivalent extraction proceeds, the similar material layers above and below the target layer undergo displacement changes under the influence of gravity and the constraints of predetermined boundary conditions.

[0064] To describe this process, displacement variables of the overlying similar material layers are introduced, where the vertical displacement of the overlying similar material layer is denoted as... The vertical displacement of the underlying similar material layer is denoted as... ;

[0065] Relative displacement between similar material layers above and below the target layer Defined as:

[0066] ;

[0067] in, Characterizing the inter-layer separation trend at the target layer due to mining operations, when This indicates that the overlying similar material layer has shifted upward relative to the underlying similar material layer;

[0068] As the simulated mining progresses, the bearing capacity of similar materials in the target stratum decreases. Gradually increase, and The change range is relatively small, thus the relative displacement The size gradually increases as mining progresses;

[0069] When relative displacement When the gap is increased to the point that a gap is formed between similar material layers above and below the target layer, it is considered that a delamination space has been formed at the target layer.

[0070] To characterize the formation state of the delamination space, a delamination thickness variable is introduced. The thickness of the delamination With relative displacement The relationship can be represented as:

[0071] ;

[0072] in, Characterizing the actual thickness of the delamination space formed at the target layer, when It was initially believed that no separation space had formed;

[0073] when When the value is greater than zero and persists during the mining process, it is considered that a stable delamination space has been formed in the target layer. This delamination space serves as the initial spatial condition for subsequent short-term enhanced disturbances, delamination stability determination, and filling grout injection.

[0074] The delamination space formed by the above method is formed entirely from the natural evolution of the stress state and displacement response inside the similar material model, rather than artificially prefabricated voids. This ensures the rationality of the delamination space in terms of geometry and mechanical background, and provides a reliable basis for the simulation preparation of the subsequent delamination filling press.

[0075] S2. After the delamination is formed, grouting is not performed. A short-term enhanced disturbance is applied to the delamination. If the geometry of the delamination can return to the state before the disturbance after the disturbance ends and does not continue to expand or close, the delamination is determined to be a lockable delamination. Otherwise, the disturbance is repeated until the determination condition is met.

[0076] Furthermore, in step S2, the step of applying a short-time enhancement perturbation to the delamination includes:

[0077] After the simulated mining is completed and the delamination is formed, and before the filling slurry is injected into the delamination space, a short-term enhanced disturbance is applied to the delamination.

[0078] The short-term enhanced disturbance is an enhanced disturbance relative to the disturbance intensity applied during the simulated mining process, so that the delamination produces a larger response in a short period of time than at the end of the mining phase.

[0079] Furthermore, in step S2, if the delamination geometry can return to its pre-disturbance state after the disturbance ends and does not continue to expand or close, then the step of determining the delamination as a lockable delamination includes:

[0080] After the short-term enhanced disturbance ends, the observation phase of the delamination state begins;

[0081] During the observation phase of the delamination state, it is determined whether the geometric morphology of the delamination continues to evolve over time;

[0082] When the geometry of the delamination no longer expands or closes during the observation phase and can return to the state before the disturbance, the delamination is determined to be a lockable delamination.

[0083] Furthermore, in step S2, the step of determining whether the delamination geometry has reverted includes:

[0084] Determine the thickness variation and spatial distribution range of the delamination;

[0085] When the thickness and spatial distribution of the delamination return to the pre-disturbance state after the short-term enhanced disturbance ends, and no longer change continuously over time during the observation period, it is determined that the geometry of the delamination can return to the pre-disturbance state.

[0086] Specifically, after the delamination is formed, the filling grout is not injected. Instead, a short-term enhanced disturbance is applied to the delamination. After the disturbance ends, the delamination status observation stage is entered. By judging the time sequence of the change in delamination thickness and the spatial distribution range, it is determined whether the delamination is a lockable delamination, thus providing controllable initial conditions for the subsequent grouting stage.

[0087] The short-term enhanced disturbance is set after the simulated mining is completed and the delamination is formed, and before the filling grout is injected into the delamination space. This allows the delamination to undergo a controlled disturbance and response regression verification process before grouting, thus avoiding the grouting process when the delamination is still in a state of continuous evolution.

[0088] When implementing short-term enhanced disturbance, the enhanced disturbance can be achieved by optionally changing at least one of the loading amplitude, loading rate or loading rhythm, wherein the loading amplitude represents the magnitude of the applied load, the loading rate represents the rate of change of the applied load over time, and the loading rhythm represents the time series form in which the applied load is applied continuously or in a stepwise manner.

[0089] The enhancement of short-term enhanced disturbance is characterized by a relative definition, that is, the disturbance intensity of short-term enhanced disturbance is higher than the disturbance intensity applied during the simulated mining process, so that the delamination produces a larger response in a short time than the mining end stage. The disturbance intensity can be characterized by the change in loading amplitude, the change in loading rate, or the change in loading rhythm.

[0090] Introducing disturbance intensity parameters Indicates the short-term enhanced disturbance intensity, introducing This represents the intensity of disturbance during the simulated mining process, and the enhanced disturbance satisfies:

[0091] ;

[0092] in, To enhance the intensity of the disturbance in a short period of time, To simulate the disturbance intensity during mining, both can be selected as any unified measure among the changes in loading amplitude, loading rate, or loading rhythm.

[0093] During short-term enhanced perturbation, the geometry of the delamination undergoes a transient response. To enable operable determination of the delamination geometry, a delamination thickness is introduced. Exhibition of the separated layer space Two types of characterization, among which For time variables, Indicates the separation of layers in time The thickness value, Indicates the separation of layers in time Spatial display range value;

[0094] The start time of the short-term enhanced disturbance is denoted as The end time of the short-term enhanced disturbance is recorded as After the disturbance ends, the observation phase of the delamination state begins, and the start time of the observation phase is... The end time of the observation phase is recorded as ,in Optionally determined by a preset observation duration, or triggered by a criterion that the delamination geometry enters a stable change range;

[0095] To reflect the judgment logic of the delamination geometry regression, a reference time before the short-term enhanced perturbation is taken. ,in and with Indicates the reference thickness before the disturbance, in Indicates the reference distribution range before the disturbance;

[0096] During the delamination observation phase, the thickness deviation was calculated separately. Deviation from the display area Defined as:

[0097] ;

[0098] ;

[0099] in, This indicates the deviation of the delamination thickness from the reference thickness before the disturbance. This indicates the deviation of the delamination distribution range from the reference distribution range before the disturbance;

[0100] To determine whether the delamination geometry has reverted to its pre-disturbance state, a thickness regression tolerance can be optionally set. With range regression tolerance ,in This indicates the allowable deviation range for thickness regression. This indicates the allowable deviation range for the regression of the distribution range, and both can be determined based on the scale, measurement resolution, and process fluctuation level of the similar material model.

[0101] When there is a moment during the observation phase ,in ,satisfy:

[0102] ;

[0103] ;

[0104] It is assumed that the delamination thickness and spatial distribution range of the delamination return to the corresponding state before the disturbance during the observation period, thus satisfying the judgment basis that the delamination geometry can return to the state before the disturbance.

[0105] In determining whether the geometry of the delamination continues to evolve over time, this embodiment focuses on the continuous changing trend of the delamination thickness and distribution range during the observation period, and therefore introduces a thickness change rate. With range change rate Defined as:

[0106] ;

[0107] ;

[0108] in, This represents the rate of change of delamination thickness over time. This represents the rate of change of the extent of the delamination over time. If discrete sampling data is used, the derivative can be expressed as an approximation of the difference between adjacent sampling points.

[0109] To determine whether continuous expansion or closure will occur, a thickness change rate threshold can be optionally set. With range change rate threshold ,in This indicates the upper limit of the allowable thickness change rate. Indicates the upper limit of the allowable rate of change of the display area;

[0110] At any time during the observation period satisfy:

[0111] ;

[0112] If the above state continues to hold during the observation period, it is considered that the delamination geometry no longer continues to expand or close during the observation period, thus satisfying the judgment condition that no continuous expansion or closure occurs.

[0113] When the conditions for determining the regression of delamination thickness and distribution range are met, and the conditions for determining non-continuous expansion or closure are met, the delamination is determined to be a lockable delamination, and the subsequent filling grout injection process is initiated while keeping the external boundary conditions unchanged.

[0114] If the conditions for delamination regression and the conditions for non-continuous expansion or closure cannot be met simultaneously during the observation phase, it is considered that the delamination is still in a state of continuous evolution. It is necessary to repeat the short-term enhanced perturbation and observation and judgment process. The timing of the repeated triggering should still be before the start of grouting, and the external boundary conditions should be kept consistent to ensure that the judgments corresponding to the repeated perturbations are comparable and feasible.

[0115] S3. After the delamination is determined to be lockable, filler grout is injected into the delamination space while keeping the external boundary conditions unchanged.

[0116] Furthermore, in step S3, the step of injecting filling grout into the delamination space while keeping the external boundary conditions unchanged includes:

[0117] After the delamination is determined to be a lockable delamination, the loading conditions at the end of the simulated mining remain unchanged;

[0118] With the loading conditions remaining unchanged, filling grout is injected into the delamination space so that the grouting process is carried out under the same stress state as the delamination locking stage.

[0119] Specifically, after the delamination is determined to be lockable, filling grout is injected into the delamination space while keeping the external boundary conditions unchanged. This allows the grouting process to be carried out under the same stress state as the delamination locking stage, thereby providing a controllable initial stress environment for subsequent grout consolidation and compaction.

[0120] In this embodiment, the external boundary conditions are used to characterize the force and displacement boundary states of the externally applied or constrained similar material model. The unchanged external boundary conditions correspond to the fact that the loading conditions at the end of the simulated mining are not changed during the grouting stage, so as to ensure that the force background of the delamination space during the grouting process is consistent with the lockable delamination determination stage.

[0121] Before grouting, the loading conditions at the end of the simulated mining were first recorded after the delamination was determined to be lockable, and these loading conditions were kept unchanged throughout the subsequent grouting process.

[0122] The loading conditions may optionally include the magnitude of the applied load, the loading method, and the loading holding state, wherein the magnitude of the applied load is used to characterize the force or equivalent stress level applied to the boundary of the similar material model, the loading method is used to characterize the loading as a constant load, a stepped load, or a load that varies according to a predetermined time series, and the loading holding state is used to characterize whether it remains constant or maintains the predetermined boundary constraints during grouting.

[0123] To facilitate public disclosure and implementation, a set of loading condition parameters is introduced. This represents the boundary loading condition at the end of the simulated mining operation, where Optionally by external load Equivalent boundary stress and boundary displacement constraints It consists of one or more of the following, and satisfies the requirements during the grouting stage. To maintain the relationship;

[0124] ;

[0125] in, For the time variable of the grouting stage, For time The corresponding set of boundary loading condition parameters, This is the set of boundary loading condition parameters recorded at the end of the simulation.

[0126] When using external loads for boundary characterization The magnitude of the external load applied to the model boundary, and the relationship maintained during the grouting stage, can be expressed as:

[0127] ;

[0128] in, Grouting stage time External load, To simulate the external load at the end of mining operations;

[0129] When using equivalent boundary stress for boundary characterization The equivalent stress level applied to the model boundary, and the relationship maintained during the grouting stage, can be expressed as:

[0130] ;

[0131] in, Grouting stage time The equivalent boundary stress, To simulate the equivalent boundary stress at the end of mining;

[0132] When boundary displacement constraints are used for boundary characterization The boundary displacement constraint of the model, and the relationship maintained during the grouting stage, can be expressed as:

[0133] ;

[0134] in, Grouting stage time Boundary displacement constraint amount, To simulate the boundary displacement constraint at the end of mining;

[0135] Under the condition of constant loading, filling grout is injected into the delamination space to achieve filling and spreading of the delamination space. The filling grout may be cement-based grout, cementing material grout or other consolidable grout suitable for similar material models. The specific ratio can be determined according to the scale and expected consolidation characteristics of the similar material model.

[0136] The injection process can be achieved by a constant injection rate, a segmented injection rate, or an injection method controlled by a predetermined pressure. The injection rate is used to characterize the volume change of the slurry entering the delamination space per unit time, and the injection pressure is used to characterize the driving force that overcomes the flow resistance when the slurry enters the delamination space.

[0137] To describe the injection process, an injection volume is introduced. Indicates the time of the grouting stage. The total volume of slurry injected into the separation space is used to determine the injection flow rate. Indicates time The injected traffic satisfies the following conditions:

[0138] ;

[0139] in, To inject traffic, To accumulate the injection volume, if discrete-time sampling is used, the volume difference between adjacent sampling times can be used to approximate the derivative expression.

[0140] During the grouting stage, the filling grout enters the delamination space and spreads under the stress state of keeping the boundary loading conditions unchanged. The spreading process can naturally develop in combination with the geometry of the delamination space and the connection path, thus forming the initial filling body shape for subsequent consolidation and compaction.

[0141] The grouting process is carried out under the same stress state as the delamination locking stage. The logic is to treat grouting as a continuation of the delamination locking state, so that the delamination space will not introduce additional non-target responses due to changes in external loading conditions during grouting, thereby ensuring the continuity of the stress background between the grouting stage and the subsequent structural transition stage determination.

[0142] S4. During the grouting process, when the fluidity of the grout decreases significantly and its response to loading changes from flow-dominated to load-dominated, the grout is determined to have entered the structural transition stage.

[0143] Furthermore, in step S4, the steps for determining whether the slurry has entered the structural transition stage include:

[0144] During the process of injecting filling grout into the delamination space, the state of the grout is continuously observed;

[0145] When the deformation response of the grout gradually changes from being dominated by flow deformation to being dominated by load-bearing deformation during a continuous grouting period, and this change remains stable during subsequent grouting processes, the grout is determined to have entered the structural transition stage.

[0146] Specifically, during the continuous injection of filling grout into the delamination space, the state of the grout is continuously observed, and based on the temporal characteristics of the changes in grout fluidity and deformation response mechanism, it is determined whether the grout has entered the structural transition stage, thus providing a stage boundary basis for subsequent loading path control in the structural transition stage.

[0147] In this embodiment, the structural transition stage is used to characterize the process interval of the grout transitioning from the flow stage dominated by flow deformation to the load-bearing stage dominated by load deformation. The determination of this stage is not based on a single instantaneous phenomenon, but is confirmed by combining the evolution trend over a continuous grouting period and the stable maintenance characteristics in the subsequent grouting process.

[0148] During grouting, the grout exhibits flow and spread behavior driven by pressure and flow rate within the delamination space, and in the early stage, it mainly shows flow deformation response.

[0149] As grouting continues, the deposition of solid components inside the grout, the enhancement of interparticle interactions, or the development of cementation reactions will cause the fluidity to gradually decrease, thereby changing the deformation response mode of the grout under the same boundary loading conditions.

[0150] Introducing time variables in the grouting stage Introducing cumulative injection volume With injected flow ,in Indicates the time from the start of grouting The volume of slurry that has entered the delamination space. Indicates time The injected traffic satisfies the following conditions:

[0151] ;

[0152] If discrete sampling data is used, the volume difference between adjacent sampling times can be used to approximate the derivative expression.

[0153] During the continuous grouting period, based on time intervals This represents the continuous grouting observation interval used to determine structural transitions, where... To observe the start time of the interval, To observe the end time of the interval, and ;

[0154] To provide an operable characterization of changes in slurry flowability, this embodiment optionally employs an equivalent flow index. It represents the equivalent flowability of the slurry in the delamination space. The equivalent flow index can be constructed based on the combination of injection pressure and flow rate.

[0155] Introducing injection pressure Indicates time The grouting pressure is used to introduce a reference flow coefficient. This represents a proportionality coefficient related to the geometry of the delamination space and the resistance to slurry flow, where This can be obtained through pre-calibration or empirical settings;

[0156] Equivalent liquidity index Optionally defined as:

[0157] ;

[0158] in, A larger value indicates that the volume of slurry entering the delamination space per unit time is larger under the same pressure conditions, reflecting that the slurry is in a more fluid state; a smaller value indicates that the flow resistance is increased, reflecting that the fluidity is reduced.

[0159] During the continuous grouting observation zone Inside, When a continuous decreasing trend is observed and the decrease reaches an identifiable level, it can be used as one of the process characteristics of a significant decrease in slurry fluidity.

[0160] To characterize the deformation response mechanism of the slurry to loading, this embodiment introduces the equivalent deformation of the filling material within the delamination space. Indicates time The corresponding deformation response, the equivalent deformation amount can be optionally composed of observables such as changes in delamination thickness, roof subsidence, or infill compression.

[0161] Further introduce deformation rate The rate of change of the equivalent deformation over time is defined as:

[0162] ;

[0163] If discrete sampling data is used, the derivative expression can be replaced by the deformation difference between adjacent sampling times.

[0164] In the stage dominated by flow deformation The changes are usually related to the flow and spreading of the grouting process, which manifests as continuous deformation under the drive of grouting and is sensitive to instantaneous pressure or flow fluctuations.

[0165] In the stage where load-bearing deformation is the primary factor The changes tend to be more related to the overall load and compression response, which is manifested as a decrease in deformation increment under given loading conditions and a reduced sensitivity to changes in flow rate;

[0166] To gradually shift the focus from flow deformation to load-bearing deformation as an essential criterion and establish an actionable standard, this embodiment optionally defines a flow dominance coefficient. Used to characterize the relative proportions of flow-driven and load-driven forces in the deformation response;

[0167] Introducing injection pressure change rate With the rate of change of injected flow rate They are defined as follows:

[0168] ;

[0169] ;

[0170] in, This represents the rate of change of injection pressure over time. This represents the rate of change of the injected flow rate over time; the difference approximation can also be used in the case of discrete sampling.

[0171] Flow dominance coefficient Optionally defined as:

[0172] ;

[0173] in, A value close to 1 indicates that the deformation response is more driven by flow rate changes and exhibits a more pronounced flow-dominated characteristic. A value close to 0 indicates that the deformation response is more driven by pressure changes and overall load constraints, exhibiting a more pronounced load-dominant characteristic.

[0174] During the continuous grouting observation zone Inside, When the value gradually decreases from a large value and enters a relatively stable range, and this stable range is maintained during the subsequent grouting process, it can be used as one of the process criteria for "gradually changing from flow deformation to load-bearing deformation and maintaining a stable transition state".

[0175] In the process of determining the structural transition stage, this embodiment synchronously references within the continuous grouting observation interval. , as well as To understand the evolutionary patterns and avoid making stage judgments based solely on the instantaneous fluctuations of a single quantity;

[0176] When the grout exhibits a continuous trend of decreasing fluidity within the continuous grouting observation period, and its deformation response mechanism gradually shifts from flow-dominated to load-bearing-dominated, and this shift remains stable during subsequent grouting processes, the grout is determined to have entered the structural transition stage, and this determination moment is used as the triggering basis for subsequent loading path abrupt change steps.

[0177] S5. Actively change the loading method during the structural transition stage to cause a sudden change in the loading path, and restore stable loading after the structural transition stage ends, so that the slurry continues to consolidate and be compacted in the delamination space.

[0178] Furthermore, in step S5, the step of causing a sudden change in the loading path includes:

[0179] After determining that the slurry has entered the structural transition stage, loading will not continue along the original loading path for the time being.

[0180] While keeping other preparation conditions unchanged, a loading change different from the original loading path is applied during the structural transition stage, causing the loading mode to change discontinuously in a short time.

[0181] After the discontinuous change is completed, the abrupt loading is terminated, and the system is restored to the stable loading mode before the structural transition stage.

[0182] Furthermore, in step S5, the step of restoring stable loading after the structural transition phase ends includes:

[0183] After the loading path abrupt change is completed, the state of the slurry is further assessed.

[0184] When the response of the slurry to changes in loading no longer changes significantly, and its load-bearing deformation characteristics remain stable during subsequent loading, the structural transition stage is considered to have ended.

[0185] After the structural transition phase is completed, the system is restored to a stable loading state, allowing the slurry to continue to solidify and compact within the delamination space.

[0186] Specifically, after determining that the slurry has entered the structural transition stage, the loading method is actively changed during the structural transition stage to cause a sudden change in the loading path. After the structural transition stage ends, stable loading is restored so that the slurry continues to consolidate and be compacted in the delamination space. This incorporates the process of the slurry transitioning from flow deformation to load-bearing deformation during the structural transition stage into a controllable stress path management process.

[0187] The loading method is used to characterize the variation of the applied load on a similar material model or delaminated filling body over time. The loading path is used to characterize the trajectory of the applied load or equivalent stress over time. The loading path abrupt change is used to characterize the loading operation that causes the trajectory to change discontinuously in a short period of time. The stable loading is used to characterize the loading state that maintains the continuous and stable evolution of loading conditions under a given loading law.

[0188] The moment at the start of the structural transition phase is denoted as... ,in The structural transition stage is determined by the structural transition stage determination in step S4, and the end time of the structural transition stage is recorded as . ,in It is determined by subsequent assessment of the stability of the slurry state;

[0189] To describe the loading process, an external load is introduced. Indicates time The corresponding load value introduces the load rate. The rate at which the applied load changes with time is defined as:

[0190] ;

[0191] If discrete sampling is used, the derivative expression can be replaced by the loading difference between adjacent sampling times.

[0192] The original loading path can optionally refer to the stable loading trajectory during a period of time before the start of the structural transition phase, denoted as... ,in This reflects the loading pattern maintained during grouting and early consolidation;

[0193] After determining that the slurry has entered the structural transition stage, loading is temporarily suspended along the original loading path. From that time onwards, the following will be terminated. The continued evolutionary process applies loading, transitioning into the loading path mutation control phase;

[0194] During the loading path mutation control stage, a loading change different from the original loading path is applied while keeping other preparation conditions unchanged. These other preparation conditions may include grouting method, boundary constraint state, and grout ratio state. Keeping other preparation conditions unchanged is used to ensure that the loading path mutation is the main control variable during the structural transition stage.

[0195] To demonstrate the mechanism of discontinuous change, this embodiment defines abrupt changes in the loading path as occurring within a short time window. The internal process causes discontinuous changes in the loading trajectory, among which... and satisfy And define the mutation magnitude for:

[0196] ;

[0197] in, This indicates the amount of change in the loaded value within the mutation time window;

[0198] The loading method can be selectively implemented through step loading to allow for discontinuous changes in loading over a short period of time. to In a short period of time Depend on Rapid changes to and increase loading speed The loading rate during this time window is significantly higher than that during the stable loading phase;

[0199] To characterize the discontinuity of mutations, the loading rate ratio can be optionally used. Describe, in which Defined as:

[0200] ;

[0201] in, This represents the length of the reference time window used to obtain the stable loading rate before the start of the structural transition phase. The denominator is the maximum loading rate within the reference time window before the start of the structural transition phase, and the numerator is the maximum loading rate within the abrupt change time window. When the value is significantly greater than 1, it indicates that the loading method exhibits a discontinuous change characteristic relative to the original loading path;

[0202] In another alternative implementation, abrupt changes in the loading path can be achieved by altering the loading rhythm, that is, converting continuous loading into stepped loading or pulsed loading. It exhibits intermittent changes within a short period of time, thus forming a loading trajectory that differs from the original continuous path;

[0203] After completing the above discontinuous changes, the mutation loading is terminated, that is, the special loading control after the mutation time window ends, so that the loading switches from the mutation control stage to the stable loading stage.

[0204] Then, the loading method was restored to the stable loading mode before the structural transition phase, that is, after the abrupt loading was completed. Adjusted to be with The corresponding continuous loading pattern is consistent or equivalent to the loading pattern, so that the subsequent consolidation process can continue under a stable loading background.

[0205] The logic of restoring stable loading is to treat abrupt loading as a phased control action within the structural transition stage. After this action is completed, the loading rules are returned to the same as the previous one, so as to maintain the controllability and repeatability of the method's operation process.

[0206] After the sudden change in the loading path is completed, the state of the slurry is further assessed to determine whether the structural transition stage has ended.

[0207] The slurry state can be determined by whether the slurry response to load changes still changes significantly and whether the bearing deformation characteristics remain stable. The slurry response to load changes can be characterized by the sensitivity of the deformation increment to the load increment.

[0208] To disclose an implementable determination method, a loading sensitivity coefficient is introduced. This indicates the sensitivity of the deformation response to changes in loading, where The equivalent deformation of the filling material within the delamination space is defined as:

[0209] ;

[0210] in, This represents the change in equivalent deformation within adjacent observation time windows. This represents the change in load applied inside and outside the corresponding time window. The change in the value is used to reflect the response characteristics of the filling body when it transitions from flow control to load control;

[0211] During subsequent loading processes, No more significant fluctuations occurred, and the equivalent deformation amount When the structural transition phase ends, the structural deformation characteristics show stable changes over time. This moment is recorded as... ;

[0212] After the structural transition phase is completed, the system is restored to a stable loading state and maintained, allowing the slurry to continue to consolidate and compact within the delamination space. The compaction process can be understood as the process in which the pore structure inside the filling material is gradually adjusted, the deformation rate decreases, and a stable load-bearing structure is formed under stable loading conditions.

[0213] S6. Apply a controlled disturbance load in the later stage of slurry consolidation. If the response path, stiffness, or deformation characteristics of the filling body change irreversibly when the loading is restored after the disturbance, the filling compaction body is determined to be formed.

[0214] Furthermore, in step S6, if the response path, stiffness, or deformation characteristics of the filling body undergo irreversible changes during the recovery loading after disturbance, the steps to determine that the filling compaction body has been formed include:

[0215] In the later stage of slurry consolidation, while keeping other preparation conditions unchanged, a disturbance loading with controlled amplitude is applied to the formed filling body;

[0216] After the disturbance loading ends, the loading state is restored to that before the disturbance, and the response behavior of the filling body during the restoration loading process is compared and judged.

[0217] When the response behavior after reloading shows a persistent trend of change relative to the state before the disturbance, and this trend does not regress during subsequent loading processes, the filling pressure entity is determined to be formed successfully.

[0218] Specifically, in the later stage of slurry consolidation, a controlled amplitude disturbance load is applied to the formed filling body, and after the disturbance load ends, the loading state before the disturbance is restored. By comparing the response behavior during the restoration loading process, if it is confirmed that the response path, stiffness or deformation characteristics of the filling body have undergone irreversible changes, the filling compaction body is determined to be formed, thus incorporating the termination criterion for the formation of the filling compaction body into the executable loading and judgment process.

[0219] The later stage of grout consolidation corresponds to the stage where the filling grout has completed its main spreading and entered the stage where the load-bearing structure gradually stabilizes. In this stage, the filling body gradually forms a stable load-bearing skeleton under the action of external load, and its deformation response gradually transitions from the early flow compaction to a compression and adjustment process dominated by structural load-bearing.

[0220] After entering the later stage of slurry consolidation, a disturbance loading with controlled amplitude is applied to the filling body while keeping other preparation conditions unchanged. The other preparation conditions may include boundary constraint state, grouting termination state and stable loading mode. Keeping other preparation conditions unchanged is to ensure that the disturbance loading becomes the main variable in the determination of this stage.

[0221] Amplitude-controlled perturbation loading is used to introduce a controlled external excitation without changing the overall preparation conditions, so that the filling body undergoes identifiable loading perturbation in a short period of time, thereby providing a triggering condition for determining whether an irreversible load-bearing structure has been formed.

[0222] To describe the loading process, a baseline load before the disturbance is introduced. This indicates the applied load level before the start of disturbance loading, and introduces the loading function during disturbance loading. Indicates the time of the disturbance loading phase. External loads introduce disturbance amplitude This represents the maximum offset of the disturbance load relative to the reference load, and satisfies:

[0223] ;

[0224] in, The start time of the disturbance loading. The end time of the perturbation loading. Used to characterize the magnitude of the disturbance loading, amplitude controlled representation The preset strategy limits the range to an identifiable range that does not introduce non-target damage, and the specific amplitude can be optionally determined based on the scale of the similar material model and the load-bearing level of the filling body;

[0225] The perturbation loading can be implemented in the following ways: step perturbation, pulse perturbation, or short-period reciprocating perturbation. Step perturbation corresponds to loading the material by a process that rapidly changes the load from a single point to a continuous flow of energy within a short period of time. Adjust to And stay there for a period of time before returning Pulsating disturbances correspond to a rapid drop after a single loading peak is applied within a short period of time, while short-period reciprocating disturbances correspond to... Several small-cycle loading changes are applied internally;

[0226] After the disturbance loading ends, the loading state is restored to that before the disturbance, that is, the external load is restored to the baseline loading. And continue to apply the load in a stable manner, thus entering the recovery loading observation phase;

[0227] During the recovery loading observation phase, the response behavior of the filling body during the recovery loading process is compared and judged. The comparison and judgment takes the response benchmark before the disturbance as the reference and the response evolution during the recovery loading phase after the disturbance as the observation object to identify whether irreversible changes occur.

[0228] To provide an operational characterization of the response behavior, an equivalent deformation is introduced. Indicates the time of the filling material The deformation response, with reference time before the disturbance introduced. satisfy and with This represents the reference deformation before the disturbance, and introduces the start time of the recovery loading phase. ;

[0229] To characterize the change in response path, a loading-deformation relationship curve can be optionally used, where the response path can be understood as... and The corresponding trajectory;

[0230] To characterize the change in stiffness, an equivalent stiffness is introduced. The ratio of the increment of loading to the increment of deformation of the infill body within a given observation time window is defined as:

[0231] ;

[0232] in, This indicates the change in load within and outside the observation time window. This represents the change in equivalent deformation within the same observation time window. Used to characterize the load-bearing stiffness characteristics of the filling material during the recovery loading process;

[0233] To characterize the irreversible trend of change, this embodiment introduces a recovery loading offset. The offset of the deformation during the recovery loading phase relative to the reference deformation before the disturbance is defined as:

[0234] ;

[0235] in, This reflects whether the deformation state of the filling material under recovery loading after disturbance shows a continuous shift.

[0236] During the recovery loading observation phase, When the state no longer returns to the state before the disturbance, and the offset persists during subsequent loading, it can be used as one of the characteristics of an irreversible change in deformation features.

[0237] During the recovery loading observation phase, the equivalent stiffness When the stiffness level deviates continuously from the corresponding stage before the disturbance and no longer regresses, it can be used as one of the characteristics of an irreversible change in stiffness features.

[0238] When, during the recovery loading observation phase, the loading-deformation response path shows a continuous shift relative to the path before the disturbance and forms a new stable trajectory, it can be regarded as one of the characteristics of an irreversible change in the response path.

[0239] To avoid misjudging short-term fluctuations as irreversible changes, this embodiment defines irreversible changes as changes that form a continuous trend during the recovery loading phase and remain unchanged during subsequent loading processes.

[0240] Therefore, we introduce a method to observe the termination time of the recovery load. ,in ,exist Within the observation interval and The changes are continuously observed. When both the offset and stiffness changes show stable characteristics within the observation interval, the change trend is considered to be continuous.

[0241] When at least one irreversible change characteristic is met, and the change does not regress during subsequent loading, the filling pressure entity is determined to be formed, and this determination is used as the termination condition for ending the simulation preparation process.

[0242] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for simulating the preparation of a delaminated filled compacted object, characterized in that, Includes the following steps: S1. Simulate mining in a similar material model to cause relative displacement of the rock strata above and below the target stratum, forming a separation space at the target stratum; S2. After the delamination is formed, grouting is not performed. A short-term enhanced disturbance is applied to the delamination. If the geometry of the delamination can return to the state before the disturbance after the disturbance ends and does not continue to expand or close, the delamination is determined to be a lockable delamination. Otherwise, the disturbance is repeated until the determination condition is met. S3. After the delamination is determined to be lockable, filler grout is injected into the delamination space while keeping the external boundary conditions unchanged. S4. During the grouting process, when the fluidity of the grout decreases significantly and its response to loading changes from flow-dominated to load-dominated, the grout is determined to have entered the structural transition stage. S5. Actively change the loading method during the structural transition stage to cause a sudden change in the loading path, and restore stable loading after the structural transition stage ends, so that the slurry continues to consolidate and be compacted in the delamination space. S6. Apply a controlled disturbance load in the later stage of slurry consolidation. If the response path, stiffness, or deformation characteristics of the filling body change irreversibly when the loading is restored after the disturbance, the filling compaction body is determined to be formed.

2. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S1, the step of implementing simulated sampling in a similar material model includes: Similar materials in the target layer are gradually removed or equivalently extracted; As the removal or equivalent extraction proceeds, the similar material layers above and below the target layer undergo relative displacement. When relative displacement causes a gap to form between similar material layers above and below the target layer, a delamination space is formed at the target layer.

3. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S2, the step of applying a short-time enhancement perturbation to the delamination includes: After the simulated mining is completed and the delamination is formed, and before the filling slurry is injected into the delamination space, a short-term enhanced disturbance is applied to the delamination. The short-term enhanced disturbance is an enhanced disturbance relative to the disturbance intensity applied during the simulated mining process, so that the delamination produces a larger response in a short period of time than at the end of the mining phase.

4. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S2, the step of determining that the delamination is a lockable delamination if the geometry of the delamination can return to the state before the disturbance and does not continue to expand or close after the disturbance ends includes: After the short-term enhanced disturbance ends, the observation phase of the delamination state begins; During the observation phase of the delamination state, it is determined whether the geometric morphology of the delamination continues to evolve over time; When the geometry of the delamination no longer expands or closes during the observation phase and can return to the state before the disturbance, the delamination is determined to be a lockable delamination.

5. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S2, the step of determining whether the delamination geometry has reverted includes: Determine the thickness variation and spatial distribution range of the delamination; When the thickness and spatial distribution of the delamination return to the pre-disturbance state after the short-term enhanced disturbance ends, and no longer change continuously over time during the observation period, it is determined that the geometry of the delamination can return to the pre-disturbance state.

6. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S3, the step of injecting filling grout into the delamination space while keeping the external boundary conditions unchanged includes: After the delamination is determined to be a lockable delamination, the loading conditions at the end of the simulated mining remain unchanged; With the loading conditions remaining unchanged, filling grout is injected into the delamination space so that the grouting process is carried out under the same stress state as the delamination locking stage.

7. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S4, the step of determining whether the slurry has entered the structural transition stage includes: During the process of injecting filling grout into the delamination space, the state of the grout is continuously observed; When the deformation response of the grout gradually changes from being dominated by flow deformation to being dominated by load-bearing deformation during a continuous grouting period, and this change remains stable during subsequent grouting processes, the grout is determined to have entered the structural transition stage.

8. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S5, the step of causing a sudden change in the loading path includes: After determining that the slurry has entered the structural transition stage, loading will not continue along the original loading path for the time being. While keeping other preparation conditions unchanged, a loading change different from the original loading path is applied during the structural transition stage, so that the loading mode changes discontinuously in a short time. After the discontinuous change is completed, the abrupt loading is terminated, and the system is restored to the stable loading mode before the structural transition stage.

9. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S5, the step of restoring stable loading after the structural transition phase ends includes: After the loading path abrupt change is completed, the state of the slurry is further assessed. When the response of the slurry to changes in loading no longer changes significantly, and its load-bearing deformation characteristics remain stable during subsequent loading, the structural transition stage is considered to have ended. After the structural transition phase is completed, the system is restored to a stable loading state, allowing the slurry to continue to solidify and compact within the delamination space.

10. The method for simulating the preparation of a delaminated filled compacted entity according to claim 1, characterized in that, In step S6, the step of determining that the filling compaction body is formed if the response path, stiffness, or deformation characteristics of the filling body undergo an irreversible change when the loading is restored after the disturbance includes: In the later stage of slurry consolidation, while keeping other preparation conditions unchanged, a disturbance loading with controlled amplitude is applied to the formed filling body; After the disturbance loading ends, the loading state is restored to that before the disturbance, and the response behavior of the filling body during the restoration loading process is compared and judged. When the response behavior after reloading shows a persistent trend of change relative to the state before the disturbance, and this trend does not regress during subsequent loading processes, the filling pressure entity is determined to be formed successfully.

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