Method and system for designing distance between large underground powerhouse and main transformer chamber and storage medium

Abstract

The invention belongs to the technical field of underground engineering construction, and particularly relates to a method and system for designing the distance between a large underground powerhouse and a main transformer chamber and a storage medium. According to the method and system for designing the distance between the large underground powerhouse and the main transformer room and the storage medium, the design distance between the large underground powerhouse and the main transformer room is efficiently, accurately and reasonably calculated, and scientific guidance is provided for arrangement of a large underground cavern group. According to the method, a new underground powerhouse and main transformer chamber spacing calculation formula is provided through statistical analysis and formula fitting on the basis of the principle of statistics and in combination with domestic typical large underground powerhouse size and spacing values, and simple calculation is carried out only by substituting known span and height data of the underground powerhouse and the main transformer chamber on the basis of the new formula. Therefore, the design distance between the large underground powerhouse and the main transformer room can be efficiently, accurately and reasonably calculated, and scientific guidance is provided for arrangement of a large underground cavern group.

Description

Technical Field

[0001] The invention belongs to the technical field of underground engineering construction, and in particular relates to a method, system and storage medium for designing the distance between a large underground powerhouse and a main transformer room. Background Art

[0002] Hydropower stations in the mountainous areas of southwest my country generally use underground power plants, that is, underground power plant caverns are excavated and built inside the riverside mountains to divert water for power generation. The underground caverns of hydropower stations generally include three main caverns (underground power plant, main transformer room, tailwater surge chamber) and other auxiliary caverns. The caverns are large in scale, with not only large main caverns but also a large number of caverns.

[0003] Large underground caverns are arranged in limited underground space, and the spacing between the underground powerhouse and the main transformer room is critical. The spacing between the underground powerhouse and the main transformer room refers to the thickness of the rock column between the underground powerhouse and the main transformer room of the hydropower station, that is, the horizontal distance between the upper side wall of the rock anchor beam on the downstream side of the powerhouse and the upstream side wall of the main transformer room. Figure 1 shown.

[0004] Generally speaking, the spatial arrangement of caverns should follow the principle of compactness, and the spacing between caverns should not be too large, because too large spacing will lead to increased construction costs and increased power loss during operation. However, from the perspective of surrounding rock stability, smaller spacing is not conducive to surrounding rock stability, because if the spacing between caverns is too small, cavern group effect is likely to occur, excavation and unloading between caverns will affect each other, and the surrounding rock stress redistribution area is easy to connect after cavern excavation, resulting in poor stability of surrounding rock or rock column, which will have an adverse impact on the safety and stability of caverns, increase the risk of surrounding rock disasters, or increase the cost of surrounding rock support.

[0005] Therefore, determining the distance between the underground plant and the main transformer room is a very difficult technical issue. It should not be too small or too large, and should be determined by a scientific and reasonable method that meets both rationality and practicality requirements.

[0006] At present, in traditional technology, there are several design methods for the distance between underground powerhouse and main transformer room, such as specification method, engineering analogy method, formula method, numerical simulation method, etc., which are specifically introduced as follows:

[0007] (1) Normative law

[0008] "NB / T 35011-2013 Hydropower Station Building Design Code" points out that the net distance between main caverns should not be less than 1.5 times the average excavation span of the caverns, should not be less than 2.0 times for high ground stress areas, and should not be less than 0.5 times the excavation height of the larger cavern.

[0009] This specification stipulates a larger range of values ​​for the design of the distance between the underground powerhouse and the main transformer room, but more precise values ​​are required in actual construction. Therefore, this solution is not very practical and is not easy to promote.

[0010] (2) Engineering analogy method

[0011] That is, by referring to underground factories with similar sizes, the spacing values ​​are also similar to these similar projects.

[0012] Due to the large differences between different projects, the reference and practicality of this solution are not strong.

[0013] (3) Formula method

[0014] The invention with application number CN201410230738.7 proposes a calculation formula for the optimal spacing, and the main factors considered include the respective spans of the underground powerhouse and the main transformer room, the rock strength stress ratio, the rock column hollowing rate, the confining pressure influence coefficient, the surrounding rock integrity coefficient, etc.

[0015] This scheme takes many factors into consideration, but it does not consider the height of the underground powerhouse and the main transformer room. In fact, the height of the cavern also has a certain impact on the selection of the spacing, especially in the context of the increasing height of the side walls of large underground powerhouses (underground powerhouses with an excavation span of more than 25m), this factor should not be ignored.

[0016] In addition, a similar formula to calculate the optimal spacing is also proposed in the invention with application number CN202310976250.8, but it considers fewer factors, only considering the burial depth of the cave group, the lateral pressure coefficient of ground stress, the height of the underground plant, etc., and its scientificity and rationality need to be improved.

[0017] (4) Numerical simulation method

[0018] That is, based on engineering geological conditions and relevant design parameters, a numerical model is established using finite element software for analysis and calculation to obtain the optimal design spacing.

[0019] However, the numerical simulation method has certain limitations compared to the formula method due to the large workload of modeling, calculation and analysis, and it is difficult to design the cavern spacing quickly and easily. Summary of the invention

[0020] The technical problem to be solved by the present invention is to propose a design method, system and storage medium for the distance between a large underground powerhouse and a main transformer room, so as to efficiently, accurately and reasonably calculate the design distance between a large underground powerhouse and a main transformer room, and provide scientific guidance for the layout of a large underground cavern group.

[0021] The technical solution adopted by the present invention to solve the above technical problems is:

[0022] On the one hand, the present invention provides a method for designing the distance between a large underground powerhouse and a main transformer room, comprising:

[0023] With L / s as the dependent variable, S·H·h / s 3 As independent variables, L is the distance between the underground powerhouse and the main transformer room, S is the span of the powerhouse, s is the span of the main transformer room, H is the height of the powerhouse, and h is the height of the main transformer room;

[0024] Based on the statistical analysis of the size and spacing design data of existing large underground powerhouses and main transformer rooms, L / s and S·H·h / s were obtained. 3 The calculation formula between:

[0025] According to the known span and height data of the underground powerhouse and the main transformer room whose spacing is to be determined, the spacing between the underground powerhouse and the main transformer room is calculated using the calculation formula.

[0026] Furthermore, the L / s and S·H·h / s 3 The calculation formula between is:

[0027] L / s=1.026(S·H·h / s 3 ) 0.379 .

[0028] Furthermore, the method also includes:

[0029] Adjust the calculated distance between the underground powerhouse and the main transformer room according to the actual ground stress conditions:

[0030] When the local stress value is higher than the set ground stress threshold or the rock strength stress ratio is lower than the set stress ratio threshold, the final design spacing value is based on the calculated spacing value plus the set adjustment amount; otherwise, the final design spacing value adopts the calculated spacing value.

[0031] On the other hand, the present invention also provides a system for designing the distance between a large underground plant and a main transformer room, comprising a processor and a memory, wherein the memory stores a computer program, and the processor implements the method for designing the distance between a large underground plant and a main transformer room as described above by executing the computer program.

[0032] In a third aspect, the present invention further provides a storage medium storing a computer program, which, when executed by a processor, implements the method for designing the distance between a large underground powerhouse and a main transformer room as described above.

[0033] The beneficial effects of the present invention are:

[0034] Based on the statistical analysis of the size and spacing design data of existing large-scale underground powerhouses and main transformer rooms, the present invention proposes a new calculation formula for the spacing between underground powerhouses and main transformer rooms. The formula can calculate the precise spacing value, solving the problem that the value range of the specification method is relatively general; at the same time, the formula takes into account both the cavern span and the cavern height, solving the problem that the traditional formula method does not consider all factors and lacks rationality; and the present invention only needs to substitute the known span and height data of the underground powerhouse and the main transformer room for simple calculation, solving the problem that the numerical simulation method is relatively cumbersome, has many parameters and a large workload.

[0035] Based on the above, the present invention can efficiently, accurately and reasonably calculate the design distance between a large underground powerhouse and a main transformer room, and provide scientific guidance for the layout of a large underground cavern group. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the distance between the underground powerhouse and the main transformer room;

[0037] Figure 2 is a fitted relationship diagram between the independent variables and the dependent variables selected in the embodiment of the present invention;

[0038] Figure 3 The figure is a flow chart of a method for designing the distance between a large underground powerhouse and a main transformer room in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention aims to provide a design method, system and storage medium for the spacing between a large underground powerhouse and a main transformer room, which can efficiently, accurately and reasonably calculate the design spacing between a large underground powerhouse and a main transformer room, and provide scientific guidance for the layout of a large underground cavern group. The core idea is: considering that my country has currently designed and built dozens of large underground powerhouse cavern groups, it has rich design experience and relevant data. These data and experience can provide a basis for the design of subsequent underground powerhouses. There must be certain regularities in the existing engineering data, and the design ideas for subsequent projects can be extracted; in view of this, the present invention is based on statistical principles, combined with the size and spacing values ​​of typical large underground powerhouses in China, and through statistical analysis and formula fitting, a new calculation formula for the spacing between underground powerhouses and main transformer rooms is proposed. Based on the new formula, it is only necessary to substitute the known span and height data of the underground powerhouse and the main transformer room for simple calculation, and the design spacing between the large underground powerhouse and the main transformer room can be efficiently, accurately and reasonably calculated, providing scientific guidance for the layout of large underground cavern groups.

[0040] The scheme of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0041] Example

[0042] This embodiment provides a method for designing the distance between a large underground powerhouse and a main transformer room. Figure 3 , including the following steps:

[0043] 1. Determine the independent variables and dependent variables;

[0044] In this step, first define various physical quantities, including: define L as the distance between the underground plant and the main transformer room, define S as the plant span, define s as the main transformer room span, define H as the plant height, and define h as the main transformer room height.

[0045] Based on the above definition of physical quantities, L / s is used as the dependent variable and S·H·h / s 3 as independent variable.

[0046] This embodiment selects these two variables as the independent variable and the dependent variable respectively. The reason is that: through statistical analysis of the size data and spacing design data of domestic large-scale underground power buildings and main transformer rooms, it is found that the height-to-span ratio (i.e., height divided by span) of power buildings and main transformer rooms has a relatively fixed value range (e.g., the height-to-span ratio of power buildings is generally 2.2 to 2.8), and the ratio of the spacing between caverns to the span has a relatively fixed value range. It can be considered that as the size of the cavern section changes, its cross-sectional shape satisfies a certain rule, that is, the two variables of the height-to-span ratio and the spacing-to-span ratio conform to a certain rule.

[0047] 2. Conduct statistical analysis on the size and spacing design data of existing large underground powerhouses and main transformer rooms to determine the calculation formulas for independent and dependent variables;

[0048] In this step, based on the statistical principle, statistical analysis is performed on the basis of the size data and spacing design data of domestic large underground powerhouses and main transformer rooms. It includes: referring to the corresponding parameter values ​​in the statistical table of the size and spacing of typical domestic large underground powerhouses and main transformer rooms (see Table 1) to substitute the corresponding parameters in the dependent variable and the independent variable, and calculate the logarithm of the independent variable and the dependent variable respectively, and plot them on the xy coordinate graph, where the x coordinate axis represents log(S·H·h / s 3 ), the y axis represents log(L / s), see Figure 2 , it can be seen that the points in the figure have a good linear distribution, and it can be approximately considered that there is a linear relationship between the dependent variable and the independent variable.

[0049] Table 1 Statistics of the dimensions and spacing between typical large underground powerhouses and main transformer rooms in China

[0050]

[0051]

[0052] Next, based on statistical data, the correlation between the independent variable and the dependent variable is extracted through formula fitting, and the final calculation formula is determined. The specific process is as follows:

[0053] The fitting curve is expressed as:

[0054] L / s=a(S·H·h / s 3 ) b (1)

[0055] Expressed as logarithm:

[0056] log(L / s)=loga+blog(S·H·h / s 3 ) (2)

[0057] According to the principle of least squares method, calculations are performed based on the data shown in Table 1. Table 2 shows the calculation process and results.

[0058] Table 2 Calculation table of statistical related values

[0059]

[0060]

[0061] Based on the above calculations, the following formula is derived:

[0062]

[0063] in,

[0064] The correlation coefficient r is:

[0065] Substituting the values ​​in Table 2 into formulas (4), (5) and (6), we obtain:

[0066] loga=0.3633

[0067]

[0068] Substituting the above values ​​into formula (3), we can obtain:

[0069] log(L / s)=0.3633+0.379[log(S·H·h / s 3 )-0.9292]

[0070] log(L / s)=0.0111+0.379log(S·H·h / s 3 )

[0071] log(L / s)=log 1.026+0.379log(S·H·h / s 3 )

[0072] L / s=1.026(S·H·h / s3 ) 0.379 (7)

[0073] The above formula (7) is the calculation formula between the independent variable and the dependent variable determined in this embodiment.

[0074] Compared with the traditional calculation formula, the calculation formula proposed in this embodiment needs to consider the underground plant span S, the main transformer room span s, the plant height H, and the main transformer room height h; if the main transformer room height is not considered in formula (7), the calculated correlation coefficient will decrease, which can prove that the main transformer room height has a certain influence on determining the spacing, which indirectly reflects that the calculation formula of this embodiment is more reasonable than the traditional calculation formula that does not consider the main transformer room height.

[0075] In addition, this formula can calculate the precise spacing value, solving the problem that the value range of the standard method is relatively general. It only needs to substitute the known span and height data of the underground plant and main transformer room for simple calculation, solving the problem that the numerical simulation method is relatively cumbersome, has many parameters and a large workload.

[0076] 3. Use the above calculation formula to calculate the distance between the underground powerhouse and the main transformer room;

[0077] In this step, based on the above formula (7), the span S of the underground plant, the span s of the main transformer room, the height H of the plant and the height h of the main transformer room to be designed are substituted to calculate the design distance L between the plant and the main transformer room.

[0078] It should be noted that the calculated spacing value can be adjusted according to the actual ground stress conditions to make the spacing value more consistent with the geological conditions. For example, when the ground stress value is high or the rock strength stress is low, the spacing value can be greater than the calculated value, that is, a certain margin is added on the basis of the calculated value; when the ground stress value is not large or the rock strength stress ratio is not low, the spacing value can adopt the calculated value.

[0079] Case application: The height of the underground powerhouse of a hydropower station is 79.3m, the span is 27.4m, the height of the main transformer room is 24.4m, and the span is 22m. The calculation formula provided in this embodiment is used to calculate that the distance between the powerhouse and the main transformer room is 41.5m, which is generally close to the actual design distance of 42m. This shows that this method is more reasonable and can be used as the basis for the design of the distance between the powerhouse and the main transformer room.

[0080] Finally, it should be noted that the above embodiments are only preferred implementations and are not intended to limit the present invention. It should be pointed out that for those skilled in the art, several modifications, equivalent replacements, improvements, etc. can be made without departing from the scope of the present invention and the scope of protection of the claims, and all of these should be included in the protection scope of the present invention.

Claims

1. A method for designing the distance between a large underground powerhouse and a main transformer room, characterized in that: include: With L / s as the dependent variable, S·H·h / s 3 As independent variables, L is the distance between the underground powerhouse and the main transformer room, S is the span of the powerhouse, s is the span of the main transformer room, H is the height of the powerhouse, and h is the height of the main transformer room; Based on the statistical analysis of the size and spacing design data of existing large underground powerhouses and main transformer rooms, L / s and S·H·h / s were obtained. 3 The calculation formula between: According to the known span and height data of the underground powerhouse and the main transformer room whose spacing is to be determined, the spacing between the underground powerhouse and the main transformer room is calculated using the calculation formula.

2. A method for designing the distance between a large underground powerhouse and a main transformer room as claimed in claim 1, characterized in that: The L / s and S·H·h / s 3 The calculation formula between is: L / s=1.026(S·H·h / s 3 ) 0.379 。 3. A method for designing the distance between a large underground powerhouse and a main transformer room as claimed in claim 1 or 2, characterized in that: The method further includes: Adjust the calculated distance between the underground powerhouse and the main transformer room according to the actual ground stress conditions: When the local stress value is higher than the set ground stress threshold or the rock strength stress ratio is lower than the set stress ratio threshold, the final design spacing value is based on the calculated spacing value plus the set adjustment amount; otherwise, the final design spacing value adopts the calculated spacing value.

4. A system for designing the distance between a large underground powerhouse and a main transformer room, comprising a processor and a memory, wherein a computer program is stored in the memory, characterized in that: The processor executes the computer program to implement the method for designing the distance between a large underground powerhouse and a main transformer room as described in any one of claims 1 to 3.

5. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for designing the distance between a large underground powerhouse and a main transformer room as described in any one of claims 1 to 3 is implemented.

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