Earth and rockfill dam construction rolling parameter optimization method

Abstract

The invention relates to an earth and rockfill dam construction rolling parameter optimization method. The method comprises the following steps: S1, establishing a compaction quality evaluation model; s2, earth and rockfill dam material rolling construction efficiency is measured; s3, establishing a rolling parameter optimization model; and S4, solving the optimization model. According to the method, the optimal rolling parameter combination is sought while the construction efficiency and the compaction quality are considered, and an effective way is provided for determining the reasonable and efficient earth and rockfill dam rolling parameter combination.

Description

Technical Field

[0001] The invention belongs to the technical field of earth-rock material rolling quality control in earth-rock dam construction, and in particular relates to a method for optimizing rolling parameters in earth-rock dam construction. Background Art

[0002] Rolling parameters and rolling technology directly affect the compaction quality of earth materials in earth-rock dams, have a significant impact on the deformation properties of earth-rock dams during construction and operation, and are the key to controlling uneven settlement of earth-rock dams.

[0003] At present, the step-by-step convergence method is often used in engineering to determine the combination of rolling parameters (travel speed, vibration frequency, loose paving thickness, etc.). Each time a rolling parameter is changed, the other rolling parameters are fixed. After obtaining the optimal value of a single rolling parameter, it is fixed, and then the next rolling parameter is changed until a set of optimal rolling parameters is finally obtained. This approach considers each rolling parameter independently, but in fact the compaction degree of soil and stone depends on the combined effect of multiple rolling parameters. The change of one rolling parameter will affect the values ​​of other rolling parameters. Therefore, the step-by-step convergence method can only obtain a local optimal or temporarily feasible rolling parameter combination, but cannot guarantee the global optimal; at the same time, in the actual construction process, in addition to ensuring the compaction quality, construction efficiency also needs to be considered.

[0004] Therefore, in order to solve the above problems, a new method for optimizing compaction parameters of earth-rock dam is proposed. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for optimizing rolling parameters in earth-rock dam construction, while taking into account construction efficiency and compaction quality, to seek the optimal rolling parameter combination, thereby providing an effective way to determine a reasonable and efficient earth-rock dam rolling parameter combination.

[0006] The present invention solves the technical problem by the following technical solutions:

[0007] A method for optimizing rolling parameters in earth-rock dam construction, the method establishing a compaction quality evaluation model based on field rolling tests to achieve the association between different rolling parameters and rolling processes; establishing a rolling parameter optimization model with the goal of maximizing construction efficiency under the condition of satisfying compaction quality constraints; and obtaining a global optimal rolling parameter combination that takes both compaction quality and construction efficiency into consideration by solving the model;

[0008] The steps of the method are:

[0009] S1. Establish a compaction quality assessment model: Use on-site rolling tests and test pit tests to collect multiple sets of earth-rock dam material compaction quality and rolling parameters corresponding to the collection location, including the roller mechanical tonnage W, roller travel speed v, rolling number N, earth-rock dam material loose laying thickness h and earth-rock dam material moisture content ω;

[0010] The relationship between the above rolling parameters and compaction quality D is analyzed, and a quantitative model between the two is established:

[0011] D=f(W,N,h,ω,v) (1)

[0012] The above quantitative model was established by multiple regression method;

[0013] S2. Measurement of construction efficiency of earth-rock dam material rolling

[0014] The construction efficiency E of earth-rock dam material rolling is measured by the volume of earth-rock paving per unit time and is calculated as follows:

[0015]

[0016] Where: Paving volume V = LBh;

[0017] Rolling time T = LN / v;

[0018] L represents the rolling length;

[0019] B represents the width of the roller;

[0020] S3. Establishing a rolling parameter optimization model

[0021] Under the premise of ensuring compaction quality, each rolling parameter is taken as a variable to seek its reasonable value to maximize the construction efficiency and establish a rolling parameter optimization model:

[0022]

[0023] Among them: Min means the objective minimization;

[0024] G represents the inverse of rolling construction efficiency;

[0025] D is the compaction mass, (degree of compaction or dry density);

[0026] D0 is the standard compaction quality required for construction (standard compaction degree or standard dry density);

[0027] W i , i=1,2,..n, are the tonnages of different roller compactors;

[0028] h min 、h max is the minimum and maximum value of loose paving thickness;

[0029] ω min ,ω max is the minimum and maximum value of soil moisture content;

[0030] v min 、vmax is the minimum and maximum value of the travel speed;

[0031] N min 、N max is the minimum and maximum number of rolling passes;

[0032] S4. Optimization model solution

[0033] The single-objective optimization algorithm is used to solve the rolling parameter optimization model and obtain the optimal rolling parameter combination N. * , W * 、v * 、h * ,ω * And the corresponding maximum construction rolling efficiency E * ; N * , W * 、v * 、h * and ω * They respectively represent the optimal number of rolling passes, optimal machine tonnage, optimal travel speed, optimal loose paving thickness and optimal soil moisture content, and determine the optimal rolling parameter combination while ensuring compaction quality and rapid filling.

[0034] The positive effects that the present invention can produce are:

[0035] 1. The present invention aims to optimize the rolling parameters under the premise of meeting the compaction quality requirements and efficient construction, so as to provide a basis for reasonably formulating the rolling parameter control standards and thus ensuring the fast and good construction of earth-rock dams.

[0036] 2. The present invention establishes an optimization model for rolling parameters of earth-rock dams to seek global optimal rolling parameters, thereby solving the limitation that the rolling parameters determined by the conventional stepwise convergence method have local optimality.

[0037] 3. The present invention takes into account the work efficiency problem during the rolling construction of the earth-rock dam, and realizes rapid construction under the premise of ensuring compaction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0040] like Figure 1As shown in the figure, a method for optimizing rolling parameters for earth-rock dam construction is innovative in that: a compaction quality evaluation model is established based on the rolling test results, and a rolling parameter control standard optimization model that takes into account both compaction quality and construction efficiency is established based on conditions such as compaction degree as constraints, and finally an algorithm for optimizing rolling parameters is designed; the steps of the method are:

[0041] Step 1: Establish a compaction quality assessment model

[0042] First, a field rolling test was conducted to carry out a test pit test to collect enough sets of soil compaction quality and the rolling parameters corresponding to the collection location, including: roller tonnage W, roller travel speed v, number of rolling passes N, loose soil thickness h and soil moisture content ω.

[0043] Then, the relationship between the above rolling parameters and compaction quality D (dry density or compaction degree) is analyzed, and a quantitative model between the two is established:

[0044] D=f(W,N,h,ω,v)

[0045] The above quantitative model is established by the multivariate regression method: taking each rolling parameter as a variable, constructing the multivariate regression equation of compaction quality, further constructing the X matrix, Y matrix, regression coefficient β matrix and error matrix ε, the multivariate regression model of compaction quality can be written as:

[0046] Y=X·β+ε

[0047] Among them: the error ε obeys the normal distribution with an expectation of 0, and the regression coefficient β matrix is ​​calculated using the least squares method:

[0048] β=(X T ·X) -1 ·X T ·Y

[0049] Finally, the compaction quality multivariate regression model was obtained.

[0050] Step 2: Measurement of construction efficiency of earth-rock dam material rolling

[0051] The construction efficiency E of earth-rock dam material rolling is measured by the volume of earth-rock paving per unit time and is calculated as follows:

[0052]

[0053] Among them: paving volume V = LBh; rolling time t = LN / v; L represents the rolling length; B represents the width of the roller.

[0054] Step 3: Establish a rolling parameter optimization model

[0055] The compaction quality evaluation model and the construction efficiency model are both functions of the rolling parameters W, N, h, ω, and v. Therefore, the optimization variable of the rolling parameter control standard optimization model is A = (W, N, h, ω, v), and each rolling parameter takes the upper and lower limits based on engineering experience. Under the premise of ensuring the compaction quality (that is, the compaction quality must not be less than the standard compaction quality required by the construction), each rolling parameter is used as a variable to seek its reasonable value to maximize the construction efficiency.

[0056] Therefore, the following rolling parameter optimization model is established:

[0057]

[0058]

[0059] Among them: Min means the objective minimization;

[0060] G represents the inverse of rolling construction efficiency;

[0061] D is the compaction quality (compactness or dry density);

[0062] D0 is the standard compaction quality required for construction (standard compaction degree or standard dry density);

[0063] W i , i=1,2,..n, are the tonnages of different roller compactors;

[0064] h min 、h max is the minimum and maximum value of loose paving thickness;

[0065] ω min ,ω max is the minimum and maximum value of soil moisture content;

[0066] v min 、v max is the minimum and maximum value of the travel speed;

[0067] N min 、N max The minimum and maximum values ​​for the number of rolling passes.

[0068] Step 4: Optimize model solution

[0069] The single-objective optimization algorithm is used to solve the rolling parameter optimization model and obtain the optimal rolling parameter combination N. * , W * 、v * 、h * and v * And the corresponding maximum construction rolling efficiency E *If the model is a linear optimization problem, single-objective linear programming is used to solve it; if the model is a nonlinear optimization problem, genetic algorithm, simulated annealing algorithm or ant colony algorithm optimization method is used to solve it.

[0070] N * , W * 、v * 、h * and ω * They respectively represent the optimal number of rolling passes, optimal machine tonnage, optimal travel speed, optimal loose paving thickness and optimal soil moisture content. Thus, the optimal combination of rolling parameters is determined while ensuring compaction quality and rapid filling.

[0071] According to the method described in the present invention, for a reservoir expansion project in Tianjin, rolling parameters are optimized based on the rolling test pit data to obtain a compaction quality evaluation model:

[0072] y=89.1501+1.3747x1+1.1549x2-0.0428x3-16.8462x4-10.57x5

[0073] Among them: x1 represents the machine tonnage;

[0074] x2 represents the number of rolling times;

[0075] x3 represents the loose laying thickness;

[0076] x4 represents the moisture content of soil;

[0077] x5 represents the travel speed.

[0078] Model determination coefficient R 2 is 0.925, and can pass the F test. According to the model, it can be seen that the compaction degree of soil increases with the increase of machine tonnage, increases first and then tends to be flat with the increase of rolling times, and decreases with the increase of loose paving thickness, moisture content and roller travel speed, which is consistent with the actual engineering practice. Among them, the average absolute error between the calculated compaction degree and the actual compaction degree is 0.44%, and the maximum absolute error is 1.19%. It further shows that the model has sufficient accuracy and can be used for subsequent evaluation and prediction.

[0079] The compaction parameter optimization model was solved according to the designed genetic algorithm, and finally a compaction parameter combination that can ensure both compaction quality and construction efficiency was found for the project: 22t roller, low-vibration rolling 4 times, loose paving thickness 44cm, moisture content 21.28%, and travel speed 2.32km / h. Among them, considering the actual construction process, the loose paving thickness should be controlled at about 45cm, the roller speed should be controlled between 2.3 and 2.5km / h, and the soil moisture content should be controlled between 21% and 22%. At this time, the optimal efficiency value under the corresponding optimal compaction parameter combination is 0.089m3 / s(The objective function value corresponds to 11.24s / m 3 ), which is 320.4m 3 / h(1 roller compactor).

[0080] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A method for optimizing rolling parameters in earth-rock dam construction, characterized in that: The method is based on field rolling tests, establishes a compaction quality evaluation model, and realizes the association between different rolling parameters and rolling processes; under the condition of satisfying the compaction quality constraint, establishes a rolling parameter optimization model with the goal of maximizing the construction efficiency; by solving the model, the global optimal rolling parameter combination that takes into account both the compaction quality and the construction efficiency is obtained; The steps of the method are: S1. Establish a compaction quality assessment model: Use on-site rolling tests and test pit tests to collect multiple sets of earth-rock dam material compaction quality and rolling parameters corresponding to the collection location, including the roller mechanical tonnage W, roller travel speed v, rolling number N, earth-rock dam material loose laying thickness h and earth-rock dam material moisture content ω; The relationship between the above rolling parameters and compaction quality D is analyzed, and a quantitative model between the two is established: D=f(W,N,h,ω,v) (1) The above quantitative model was established by multiple regression method; S2. Measurement of construction efficiency of earth-rock dam material rolling The construction efficiency E of earth-rock dam material rolling is measured by the volume of earth-rock paving per unit time and is calculated as follows: Where: Paving volume V = LBh; Rolling time T = LN / v; L represents the rolling length; B represents the width of the roller; S3. Establishing a rolling parameter optimization model Under the premise of ensuring compaction quality, each rolling parameter is taken as a variable to seek its reasonable value to maximize the construction efficiency and establish a rolling parameter optimization model: Among them: Min means the objective minimization; G represents the inverse of rolling construction efficiency; D is the compaction mass, (degree of compaction or dry density); D0 is the standard compaction quality required for construction (standard compaction degree or standard dry density); W i ,i=1,2,..n, represents the tonnage of different rollers; h min 、h max is the minimum and maximum value of loose paving thickness; ω min ,ω max is the minimum and maximum value of soil moisture content; v min 、v max is the minimum and maximum value of the travel speed; N min 、N max is the minimum and maximum number of rolling passes; S4. Optimization model solution The single-objective optimization algorithm is used to solve the rolling parameter optimization model and obtain the optimal rolling parameter combination N. * , W * 、v * 、h * ,ω * And the corresponding maximum construction rolling efficiency E * ; N * , W * 、v * 、h * and ω * They respectively represent the optimal number of rolling passes, optimal machine tonnage, optimal travel speed, optimal loose paving thickness and optimal soil moisture content, and determine the optimal rolling parameter combination while ensuring compaction quality and rapid filling.

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