Arrangement design method of circular grouting reinforcement with water stop requirement

Abstract

The invention discloses an arrangement design method of a circular grouting reinforcement with a water stop requirement, and relates to the technical field of underground engineering construction. The circular grouting reinforcement bodies are reasonably arranged, so that the economical efficiency and the construction efficiency of grouting are improved. The method comprises the following specific steps: step 1, determining an optimal slurry diffusion radius; 2, calculating the number of reinforcement bodies arranged in a rhombus shape; 3, the grouting utilization rate of rhombic arrangement is calculated; and 4, comparing and selecting an arrangement mode. By optimizing the slurry diffusion radius and the reinforcement arrangement mode, the economical efficiency and the construction efficiency of the grouting project can be remarkably improved, and the maximization of comprehensive benefits is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of underground engineering construction, and particularly relates to a design method for arranging circular grouting reinforcement bodies with water stopping requirements. BACKGROUND

[0002] Grouting reinforcement is widely used in the field of geotechnical engineering and plays a very important role in safety protection. Among them, the grouting reinforcement with water stopping requirements requires that there should be no ungrouted area between adjacent grouting reinforcement bodies. In actual engineering design, the arrangement of grouting reinforcement bodies is mainly designed by experience from the safety point of view at present, which not only causes slow construction speed and low efficiency, but also makes the engineering cost too high and the economic benefit too low. In order to solve the problem of low construction efficiency and economic benefit caused by unreasonable arrangement of grouting reinforcement bodies, it is necessary to analyze the influencing factors of construction efficiency and economic benefit from the aspect of grouting reinforcement body arrangement, explore a scientific grouting reinforcement body arrangement design method, and realize the double improvement of construction efficiency and economic benefit. SUMMARY

[0003] The present application proposes a design method for arranging circular grouting reinforcement bodies with water stopping requirements, aiming to improve the economy and construction efficiency of grouting by reasonably arranging circular grouting reinforcement bodies. First, based on the geological conditions, planar size, depth of the grouting reinforcement area, and the performance of construction equipment, the best grout diffusion radius and grouting utilization rate are determined, and then the grouting reinforcement body arrangement mode corresponding to the best grouting utilization rate is adopted to obtain ideal construction efficiency and economic benefit.

[0004] The technical scheme of the present application is as follows:

[0005] Step one: determine the best grout diffusion radius;

[0006] According to the engineering geological conditions, grouting equipment performance and grouting depth, the best grout diffusion radius is determined with the highest construction efficiency as the target;

[0007] Step two: calculate the number of reinforcement bodies in diamond arrangement;

[0008] According to the best grout diffusion radius and the planar size of the grouting reinforcement area, the number of transverse grouting reinforcement bodies and longitudinal grouting reinforcement bodies required in diamond arrangement is calculated;

[0009] Step three: calculate the grouting utilization rate of diamond arrangement;

[0010] According to the number of transverse grouting reinforcement bodies and longitudinal grouting reinforcement bodies, the grouting utilization rate of diamond arrangement is calculated;

[0011] Step four: compare and select the arrangement mode;

[0012] The grouting utilization rate of the rhombic arrangement is compared with the grouting utilization rate of the square arrangement, and the arrangement with higher grouting utilization rate is selected as the final design scheme.

[0013] The grouting utilization rate of the rhombic arrangement in step three is calculated according to the formula ( (2m-1)(3n-1) ) / (4πmn), wherein m is the number of transverse grouting reinforcements, and n is the number of longitudinal grouting reinforcements. (2m-1)(3n-1) ) / (4πmn), wherein m is the number of transverse grouting reinforcements, and n is the number of longitudinal grouting reinforcements.

[0014] The grouting utilization rate of the square arrangement in step four is a constant value 2 / π.

[0015] The final design scheme includes the selected arrangement, the grouting hole spacing and the grout diffusion radius.

[0016] The present application can significantly improve the economy and construction efficiency of the grouting project by optimizing the grout diffusion radius and the reinforcement arrangement, and realize the maximization of comprehensive benefits.

[0017] The present application determines the grout diffusion radius with the highest construction efficiency based on the actual engineering conditions, so as to save the construction period and cost (personnel wages, energy consumption, etc.), and then selects the grouting reinforcement arrangement corresponding to the larger grouting utilization rate, so as to further save the construction period and cost (grouting materials, personnel wages, energy consumption, etc.), thereby realizing the maximization of comprehensive benefits of the construction efficiency and economic cost of the grouting project. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic diagram of square arrangement of circular grouting reinforcements according to the present application;

[0019] Figure 2 is a schematic diagram of rhombic arrangement of circular grouting reinforcements according to the present application;

[0020] Figure 3 is a graph of evolution law of grouting utilization rate with total number of grouting reinforcements according to the present application;

[0021] Figure 4 is a flow chart of grouting reinforcement arrangement design according to the present application.

[0022] MARK DESCRIPTION IN THE FIGURE:

[0023] - the radius of a single circular grouting reinforcement,

[0024] - the transverse dimension of the effective grouting area obtained by square arrangement of four circular grouting reinforcements,

[0025] - the longitudinal dimension of the effective grouting area obtained by square arrangement of four circular grouting reinforcements,

[0026] - the transverse dimension of the effective grouting area resulting from the rhombic arrangement of four circular grouting reinforcements,

[0027] - the longitudinal dimension of the effective grouting area resulting from the rhombic arrangement of four circular grouting reinforcements. DETAILED DESCRIPTION

[0028] In order to clearly illustrate the technical features of the present application, the present application will be described in detail below with specific embodiments and in conjunction with the accompanying drawings.

[0029] For a grouting reinforcement area with water-stopping requirement, there should be no ungrouted area between adjacent grouting reinforcements. There are two arrangement modes of circular grouting reinforcements that can meet this requirement: Figure 1 the square arrangement mode (the centers of four adjacent reinforcements are connected to form a square) and Figure 2 the rhombic arrangement mode (the centers of four adjacent reinforcements are connected to form a rhombus). The rectangle enclosed by the solid line in the figure is the actual effective grouting area. The ratio of the area of the effective grouting area to the total grouting construction area (the overlapping part of adjacent reinforcements is counted twice) is defined as the grouting utilization rate, which reflects the economy of grouting. In order to achieve good economic benefits of grouting, the grouting utilization rate should be as high as possible.

[0030] Figure 1 The grouting utilization rate of the square arrangement is:

[0031]

[0032] In the formula, R is the radius of a single grouting reinforcement, and are the transverse dimension and the longitudinal dimension of the effective grouting area, respectively, and according to the geometric relationship in Figure 1 , we can obtain:

[0033]

[0034] Therefore, the grouting utilization rate of four adjacent reinforcements arranged in a square is 2 / π≈0.637. Further analysis shows that the value of this grouting utilization rate does not change no matter how the number of transverse and longitudinal reinforcements is changed, that is, the grouting utilization rate of the square arrangement is a constant value of 2 / π that is not affected by any other factors.

[0035] Figure 2 The grouting utilization rate of the rhombic arrangement is:

[0036]

[0037] wherein, R is the radius of a single grouting reinforcement, and are the lateral and longitudinal dimensions of the effective grouting area, respectively. According to the geometric relationship of the isosceles triangle in Figures 1-2 , the chord length of each arc is equal to the radius of the circle ; ; ; ; ;

[0038]

[0039] According to the geometric relationship of the right triangle in Figure 2 , the following relationship is obtained:

[0040]

[0041] Thus, the grouting utilization rate of the four adjacent reinforcements arranged in a diamond shape is about 0.517.

[0042] Generally, for a diamond-shaped arrangement of m and n grouting reinforcements in the lateral and longitudinal directions, respectively, the grouting utilization rate is calculated as follows:

[0043]

[0044] It can be seen that the grouting utilization rate of the diamond-shaped arrangement depends on the number of lateral and longitudinal reinforcements. To visually demonstrate the influence law, the evolution curves of the grouting utilization rate with the total number of grouting reinforcements are calculated and plotted for the cases where the number of lateral and longitudinal reinforcements is in the ratio of 1:1, 3:1, 6:1, and 9:1, as shown in Figure 3 . Figure 3 The horizontal straight line in is the evolution curve of the grouting utilization rate of the square-shaped arrangement.

[0045] Based on the law shown in Figure 3 , we can calculate the grouting utilization rate of the diamond-shaped arrangement according to the number of lateral and longitudinal reinforcements under specific engineering conditions, compare it with the grouting utilization rate of the square-shaped arrangement 0.637, and select the arrangement corresponding to the larger grouting utilization rate to obtain better economic benefits. The number of lateral and longitudinal reinforcements depends on the planar size of the reinforcement area and the radius of a single grouting reinforcement (the grout diffusion radius). Since the planar size of the grouting reinforcement area is given by the project, we only need to determine the appropriate grout diffusion radius according to the engineering conditions, i.e., the geological conditions, the performance of the grouting equipment, and the grouting depth, to determine the grout diffusion radius with the highest construction efficiency through theoretical analysis and field tests.

[0046] Based on the above idea, we propose Figure 4The design process for the grouting reinforcement layout is shown.

[0047] First, based on the engineering geological conditions, grouting equipment performance, and grouting depth, the optimal grout diffusion radius is determined through theoretical analysis and field tests. Then, a rhomboid arrangement is implemented based on the dimensions of the grouting reinforcement zone, and the number of grouting reinforcements in the horizontal and vertical directions is calculated. Next, the corresponding grouting utilization rate is calculated based on the number of grouting reinforcements in the horizontal and vertical directions of the rhomboid arrangement. Finally, this grouting utilization rate is compared with 0.637 (the grouting utilization rate of a square arrangement), and the larger value corresponds to the reinforcement arrangement.

[0048] Example 1.

[0049] This invention is illustrated using a soil grouting reinforcement project prior to subway construction as an example. The reinforcement area is 30m long laterally, 12m wide longitudinally, and 10m deep. The soil layer consists of silty sand and (soft to fluid plastic) silty clay. The MJS method is used for grouting, and the main equipment includes a DGZ-150L MJS main unit and a KG310 borehole drilling machine.

[0050] Reference Figure 4 The design flowchart shown in this embodiment illustrates the specific steps as follows:

[0051] Step 1: Determine the optimal slurry diffusion radius;

[0052] Based on the soil characteristics (silt and silty clay), the performance parameters of the MJS grouting system, and the grouting depth of 10m, the optimal grout diffusion radius R for achieving the highest construction efficiency was determined to be 1.2m through theoretical analysis and field tests.

[0053] Step 2: Calculate the number of reinforcements arranged in a rhomboid pattern;

[0054] Based on the planar dimensions of the grouting reinforcement zone (30m long, 12m wide) and the determined grout diffusion radius (R=1.2m), the grouting reinforcement is arranged in a diamond pattern. Calculations show that 15 grouting reinforcements are needed in the transverse direction (i.e., m=15), and 7 grouting reinforcements are needed in the longitudinal direction (i.e., n=7).

[0055] Step 3: Calculate the grouting utilization rate of the diamond-shaped arrangement;

[0056] The grouting utilization rate is calculated based on the formula for the diamond-shaped grouting arrangement. = ( (2m-1)(3n-1)) / (4πmn), substituting m=15 and n=7 into the calculation: = ( * (2*15-1) * (3*7-1)) / (4 * π * 15 * 7) = ( *29 * 20) / (4 * π * 105) ≈ 0.761.

[0057] Step four: compare and select the arrangement;

[0058] The calculated grouting utilization rate of the diamond arrangement ≈ 0.761 is compared with the constant grouting utilization rate of the square arrangement = 2 / π ≈ 0.637. Because 0.761 > 0.637, it is determined to select the diamond arrangement with higher grouting utilization rate.

[0059] Final design scheme

[0060] According to the above analysis, the final grouting reinforcement arrangement design scheme of the project is: using diamond arrangement, uniformly arranging grouting holes with a spacing of , and controlling the grout diffusion radius of single-hole grouting to be 1.2m.

[0061] Through the scientific design method of the present application, under the premise of meeting the water stop requirement, the optimal arrangement scheme is selected, compared with the traditional experience design (grout diffusion radius 1.2m, reinforcement spacing 1.8m, 17 and 8 reinforcement bodies need to be arranged in the horizontal and vertical directions respectively), it is expected to save about 23% of the grouting material and construction period, and significant economic and social benefits are achieved.

[0062] There are many specific implementation approaches of the present application, and the above description is only the preferred implementation mode of the present application. It should be pointed out that for ordinary skilled persons in the technical field, several improvements can be made without departing from the principles of the present application, and these improvements should also be regarded as the protection scope of the present application.

Claims

1. A method for designing the arrangement of circular grouting reinforcements with water-stopping requirements, characterized in that, The specific steps are as follows: Step 1: Determine the optimal slurry diffusion radius; Based on engineering geological conditions, grouting equipment performance, and grouting depth, the optimal grout diffusion radius is determined with the goal of maximizing construction efficiency. Step 2: Calculate the number of reinforcements arranged in a rhomboid pattern; Based on the optimal grout diffusion radius and the planar dimensions of the grouting reinforcement zone, calculate the number of transverse and longitudinal grouting reinforcements required when using a rhomboid arrangement; Step 3: Calculate the grouting utilization rate of the diamond-shaped arrangement; Calculate the grouting utilization rate of the diamond-shaped arrangement based on the number of transverse and longitudinal grouting reinforcements. Step 4: Compare and select the layout method; The grouting utilization rate of the diamond-shaped arrangement is compared with that of the square arrangement, and the arrangement with the higher grouting utilization rate is selected as the final design scheme.

2. The method for arranging circular grouting reinforcements with water-stopping requirements according to claim 1, characterized in that, The grouting utilization rate of the diamond-shaped arrangement in step three is based on the formula ( The formula is (2m-1)(3n-1)) / (4πmn), where m is the number of transverse grouting reinforcements and n is the number of longitudinal grouting reinforcements.

3. The method for arranging circular grouting reinforcements with water-stopping requirements according to claim 1, characterized in that, In step four, the grouting utilization rate of the square arrangement is taken as a constant value of 2 / π.

4. The method for arranging circular grouting reinforcements with water-stopping requirements according to claim 1, characterized in that, The final design scheme includes the selected layout, the spacing between grouting holes, and the grout diffusion radius.

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