Analysis Method of Drainage Pipes in Retaining Walls

Abstract

The invention relates to the technical field of water conservancy engineering and discloses a retaining wall drainage pipe analysis method, comprising: intercepting specific length L data; obtaining the saturated bulk density r of the soil; s Data, obtain the wet bulk density of soil r h Data; obtain water retaining area A data; obtain the time t data of the river water level dropping from the highest water level to the drainage pipe elevation; obtain the target average drainage flow q data; obtain the maximum drainage flow Q data according to the product of the average drainage flow q data and the specific coefficient b; obtain the roughness n data; obtain the preset data of the longitudinal slope i of the drainage pipe; obtain the filling angle θ; obtain the drainage pipe diameter d data; obtain the total drainage pipe area required for the retaining wall; obtain the spacing between each drainage pipe. Through the setting of the above technical solution, the earth pressure on the retaining wall formed by the saturated water in the soil behind the retaining wall is reduced, the adverse effect of the saturated water in the soil behind the wall on the stability of the retaining wall is reduced, and the stability of the retaining wall is increased.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy engineering, and in particular to an analysis method for a retaining wall drainage pipe. Background Art

[0002] For a high retaining wall riverbank, the water level of the river is usually high in the rainy season. The soil behind the retaining wall is saturated. The water level of the mountain river rises and falls sharply, and the water level of the river drops rapidly. At this time, if the water in the gaps of the soil behind the wall cannot be quickly discharged, the soil pressure will increase. If the wall is not equipped with a reasonable drainage pipe, the wall must be designed to be very large. However, there is no solution to how many drainage pipes should be designed and how large the diameter of each pipe should be. The specifications and textbooks only stipulate that the spacing should not exceed 3 meters and the diameter should be 5 to 8 cm. It is relatively general and the design idea is not clear. Summary of the invention

[0003] The purpose of the present invention is to provide a retaining wall drainage pipe analysis method, which can solve the problem of lack of accurate analysis of retaining wall drainage pipes in the prior art.

[0004] In order to achieve the above object, the present invention provides a retaining wall drainage pipe analysis method, comprising:

[0005] Extract the specific length L data of the retaining wall;

[0006] Get the saturated bulk density of the soil behind the retaining wall r s Data, obtain the wet bulk density r of the soil behind the retaining wall h data;

[0007] Obtain the water level area A data in the soil behind the retaining wall;

[0008] Obtain the time t data for the river water level to drop from the highest water level to the drainage pipe elevation;

[0009] By formula Obtain target average drainage flow q data;

[0010] The maximum drainage flow Q data is obtained according to the product of the average drainage flow q data and the specific coefficient b;

[0011] Get roughness n data;

[0012] Obtaining preset data of the longitudinal slope i of the drainage pipe;

[0013] The ratio of the water depth of the drain pipe to the diameter of the drain pipe is a specific value less than or equal to 0.85, and the filling angle θ is obtained;

[0014] By formula Obtain the data of the diameter d of the middle drainage pipe of each retaining wall with a specific length L;

[0015] Get the total length L of the retaining wall Z , combined with the diameter d of the middle drain pipe of each retaining wall with a specific length L, the total drain pipe area required for the retaining wall is obtained;

[0016] Obtain the diameter data of commercially available drainage pipes, select a drainage pipe with one diameter, and obtain the spacing between the drainage pipes based on the drainage pipe diameter and the total drainage pipe area required for the retaining wall.

[0017] By setting up the above-mentioned technical scheme, the cross-sectional area and diameter of the drainage pipe set in the specific length L of the retaining wall can be accurately obtained, and a drainage pipe that can adapt to the fluctuation rules of water levels in different river channels can be designed. The saturated moisture in the soil behind the retaining wall can be discharged from the drainage pipe as the river channel descends, thereby reducing the earth pressure on the retaining wall formed by the saturated moisture in the soil behind the retaining wall, reducing the adverse effect of the saturated moisture in the soil behind the wall on the stability of the retaining wall, and increasing the stability of the retaining wall.

[0018] Furthermore, the specific length L data is truncated to 1m.

[0019] Furthermore, the saturated bulk density r s , wet bulk density h The data are obtained by conducting geotechnical tests on the sampled soil.

[0020] Furthermore, the water level area A is the area formed by the highest water level, the groundwater level and the retaining wall.

[0021] Furthermore, the time t data of the river water level dropping from the highest water level to the drainage pipe elevation is queried from the hydrological station database.

[0022] Furthermore, the roughness n data is obtained by querying a roughness table according to the material of the drainage pipe.

[0023] Furthermore, the drainage pipe longitudinal slope i data is preset to 3%.

[0024] Furthermore, the ratio of the water depth of the drainage pipe to the diameter of the drainage pipe is preset to 0.85.

[0025] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of a retaining wall, a drainage pipe arranged on the retaining wall and the soil behind the wall;

[0027] Figure 2 This is a schematic diagram of a drain pipe with water flowing through it.

[0028] Description of Reference Numerals

[0029] 1 retaining wall; 2 drainage pipe; 3 highest water level; 4 groundwater level. DETAILED DESCRIPTION

[0030] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0031] In the present invention, unless otherwise stated, the directional words such as "upper" and "lower" usually refer to the orientation in the assembled state. "Inside" and "outside" refer to the inside and outside relative to the outline of each component itself.

[0032] The present invention provides a retaining wall drainage pipe analysis method, such as Figure 1-Figure 2 As shown, including:

[0033] The specific length L data of the retaining wall 1 is intercepted; preferably, the specific length L data is intercepted as 1m;

[0034] Get the saturated bulk density r of the soil behind retaining wall 1 s Data, obtain the wet bulk density r of the soil behind the retaining wall 1 h Data; wherein the saturated bulk density r s , wet bulk density h The data are obtained by conducting geotechnical tests on the sampled soil.

[0035] The data of the water level area A in the soil behind the retaining wall 1 is obtained; wherein the water level area A is the area formed by the highest water level 3, the groundwater level line 4 and the retaining wall 1.

[0036] The time t data of the river channel water level dropping from the highest water level to the elevation of the drainage pipe 2 is obtained; wherein, the time t data of the river channel water level dropping from the highest water level to the elevation of the drainage pipe 2 is queried from the hydrological station database.

[0037] Combined with the specific length L data, the saturated bulk density of the soil r s Data, wet bulk density of soil h Data, water level area A data, through the formula Obtain the target average drainage flow q data; that is, combine the actual drop time of the river water level to calculate the flow rate of water discharged from the soil from the saturated state to the wet state after every 1m of retaining wall 1.

[0038] The maximum drainage flow Q data is obtained based on the product of the average drainage flow q data and the specific coefficient b; considering that the value obtained by q is the average drainage flow, not the maximum drainage flow, in order to ensure that the moisture in the soil behind the wall can be quickly discharged, the specific coefficient b is assigned to the average drainage flow q to obtain the maximum drainage flow Q.

[0039] Obtain roughness n data, wherein the roughness n data is obtained by querying a roughness table according to the material of the drainage pipe. For example, the material of the drainage pipe may be PVC, and the corresponding roughness n data can be obtained by querying a table according to the PVC material.

[0040] Obtain preset data of the longitudinal slope i of the drainage pipe 2; preferably, the preset data of the longitudinal slope i of the drainage pipe 2 is 3%.

[0041] The ratio of the water depth of the drain pipe 2 to the diameter of the drain pipe 2 is a specific value less than or equal to 0.85, and the filling angle θ is obtained; preferably, the ratio of the water depth of the drain pipe 2 to the diameter d of the drain pipe 2 is preset to 0.85. The filling angle θ is Figure 2 shown.

[0042] By formula Obtain the diameter d data of the drainage pipe 2; it should be noted that according to the open flow pipe formula, Among them, R is the water conservancy radius, A d is the cross-sectional area of ​​water flow, According to the combination of the above three formulas, we can get Based on the existing data, the diameter d of the drain pipe can be obtained. After obtaining the diameter d of the drain pipe, the total area of ​​the drain pipe required for the retaining wall can be obtained according to the actual length of the retaining wall, thereby obtaining accurate data support for the design of the drain pipe.

[0043] Get the total length L of retaining wall 1 Z , combined with the diameter d of the drainage pipe 2 in 1 of each retaining wall with a specific length L, the total drainage pipe 2 area required for the retaining wall 1 is obtained;

[0044] The diameter data of the drainage pipes 2 available on the market are obtained, a drainage pipe 2 with one diameter is selected, and the spacing between the drainage pipes 2 is obtained according to the diameter of the drainage pipe 2 and the total drainage pipe 2 area required for the retaining wall.

[0045] It should be noted that, through the formula The obtained drain pipe 2 diameter d data is the theoretical drain pipe 2 diameter per specific length L, which is used to obtain the theoretical total drain pipe 2 area. The commercially available drain pipe 2 with one selected diameter is the diameter selected after theoretical analysis and considering the drain pipe 2 required for practical application, which is used to obtain the spacing between the drain pipes 2 in practical application in combination with the total drain pipe 2 area.

[0046] By setting the above technical scheme, the cross-sectional area and diameter of the drain pipe 2 set in the specific length L of the retaining wall 1 can be accurately obtained, and the drain pipe 2 that can adapt to the fluctuation rules of water levels in different river channels can be designed. The saturated moisture in the soil behind the retaining wall 1 can be discharged from the drain pipe 2 as the river channel descends, thereby reducing the earth pressure on the retaining wall 1 caused by the saturated moisture in the soil behind the retaining wall 1, reducing the adverse effect of the saturated moisture in the soil behind the wall on the stability of the retaining wall 1, and increasing the stability of the retaining wall 1.

[0047] It should be noted that in order to prevent the soil behind the retaining wall 1 from being discharged from the drainage pipe 2 into the river channel inside the retaining wall 1 and to avoid the soil behind the retaining wall 1 from being hollowed out, the prior art usually uses well-graded sandbags, geotextiles, and palm bark as blocking measures. In the present technical solution, the above blocking measures can also be adopted.

[0048] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0049] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0050] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A retaining wall drainage pipe analysis method, characterized in that: include: Extracting specific length L data of the retaining wall (1); Get the saturated bulk density r of the soil behind the retaining wall (1) s Data, obtain the wet bulk density r of the soil behind the retaining wall (1) h data; Obtaining data of the water level area A in the soil behind the retaining wall (1); Obtain the time t data of the river water level dropping from the highest water level to the elevation of the drainage pipe (2); By formula Obtain target average drainage flow q data; The maximum drainage flow Q data is obtained according to the product of the average drainage flow q data and the specific coefficient b; Get roughness n data; Obtaining preset data of the longitudinal slope i of the drainage pipe (2); The ratio of the water depth of the drainage pipe (2) to the diameter of the drainage pipe (2) is a specific value less than or equal to 0.85, and the filling angle θ is obtained; By formula Obtain the diameter d data of the drainage pipe (2) in (1) of each retaining wall with a specific length L; Get the total length L of the retaining wall (1) z , combined with the diameter d of the drainage pipe (2) in (1) of each retaining wall of a specific length L, the total drainage pipe (2) area required for the retaining wall (1) is obtained; The diameter data of commercially available drainage pipes (2) are obtained, a drainage pipe (2) of one diameter is selected, and the spacing between the drainage pipes (2) is obtained based on the diameter of the drainage pipe (2) and the total drainage pipe (2) area required for the retaining wall.

2. The retaining wall drainage pipe analysis method according to claim 1, characterized in that: The specific length L is set to 1 m.

3. The retaining wall drainage pipe analysis method according to claim 1, characterized in that: The saturated bulk density r s , wet bulk density h The data are obtained by conducting geotechnical tests on the sampled soil.

4. The retaining wall drainage pipe analysis method according to claim 1, characterized in that: The water level area A is the area formed by the highest water level (3), the groundwater level line (4) and the retaining wall (1).

5. The retaining wall drain pipe analysis method according to claim 1, characterized in that: The time t from the highest water level of the river to the elevation of the drainage pipe (2) is retrieved from the hydrological station database.

6. The retaining wall drainage pipe analysis method according to claim 1, characterized in that: The roughness n data is obtained by querying the roughness of the material of the drainage pipe.

7. The retaining wall drain pipe analysis method according to claim 1, characterized in that: The longitudinal slope i data of the drainage pipe (2) is preset to 3%.

8. The retaining wall drain pipe analysis method according to claim 1, characterized in that: The ratio of the water depth of the drainage pipe (2) to the diameter of the drainage pipe (2) is preset to 0.85.

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