Tropical rainforest region slope excavation strategy and supporting method and system

Abstract

The invention discloses a tropical rainforest region slope excavation strategy and support method and system, and the method comprises the steps: constructing a soil slope excavation strategy: constructing a soil slope excavation slope ratio and slope height coupling algorithm, and determining the excavation modes of slopes of different heights; a rock slope excavation strategy is constructed, specifically, a rock slope excavation slope ratio and slope height coupling algorithm is constructed, and excavation modes of slopes with different heights are determined; a slope excavation and support strategy is constructed, specifically, according to the geological conditions of the slope, if the slope is judged to be a soil slope, a soil slope excavation strategy is adopted for slope excavation design; and if it is judged that the slope is a rock slope, a rock slope excavation strategy is adopted for slope excavation design. According to the method, the excavation slope ratio and slope height coupling algorithm of the soil slope and the rock slope in the tropical rainforest region is established, so that rapid construction of an excavation strategy and a protection system of any slope type and any slope height is realized, the project investment is saved on the basis of ensuring the slope safety, and the construction period is shortened.

Description

Technical Field

[0001] The present invention belongs to the technical fields of hydraulic engineering and geotechnical engineering, and particularly relates to a slope excavation strategy, a support method and a system for a tropical rainforest area. Background Art

[0002] In order to reduce the safety risks of the waste dumps in the open-pit mining of copper mines and iron mines, it is often necessary to set up flood drainage ditches at the top of the waste dumps to drain the surface water converged on the slopes. For the waste dumps located in the tropical rainforest area, the area has abundant rainfall and steep terrain. The average annual rainfall can reach 3000 mm, and the natural slope of the mountain is 30°-70°. Since the flood drainage ditches are several kilometers long, various types of soil slopes and rock slopes are distributed along the line, and the slope heights range from a few meters to dozens of meters, and even exceed 100 meters. For slopes of different types (soil slopes and rock slopes) and different heights, how to determine the suitable excavation strategy and protection system directly affects the safety, construction period and investment of the flood drainage ditch slope project. Therefore, it is necessary to establish a slope excavation strategy, a support method and a system applicable to the tropical rainforest area. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a slope excavation strategy, a support method and a system for a tropical rainforest area. By establishing a coupling algorithm between the excavation slope ratio and the slope height of soil slopes and rock slopes in the tropical rainforest area, the rapid construction of the excavation strategy and protection system for any slope type and any slope height is realized, which provides guidance for the slope construction in the tropical rainforest area, and saves project investment and shortens the construction period on the basis of ensuring slope safety.

[0004] To achieve the above purpose, the present invention provides a slope excavation strategy and a support method for a tropical rainforest area, which is characterized in that it includes:

[0005] Constructing the excavation strategy for soil slopes: constructing a coupling algorithm between the excavation slope ratio and the slope height of soil slopes, and determining the excavation methods for slopes of different heights;

[0006] Constructing the excavation strategy for rock slopes: constructing a coupling algorithm between the excavation slope ratio and the slope height of rock slopes, and determining the excavation methods for slopes of different heights;

[0007] Constructing the slope excavation and support strategy: according to the slope geological conditions, if it is determined as a soil slope, the excavation design of the slope is carried out by using the excavation strategy for soil slopes; if it is determined as a rock slope, the excavation design of the slope is carried out by using the excavation strategy for rock slopes.

[0008] As a further optimization scheme of the present invention, the excavation strategy for soil slopes is shown in the following formula (1):

[0009]

[0010] In formula (1), the function f is the coupling algorithm of the excavation slope ratio and slope height of the soil slope; H is the slope height, with the unit of m; i is the excavation slope ratio of the slope; i 1 is the excavation slope ratio of the first-level slope, i 2 is the excavation slope ratio of the second-level slope, and so on; i 8+ is the excavation slope ratio of slopes above the eighth level.

[0011] As a further optimization scheme of the present invention, for the excavation strategies S 1 、S 2 and S 3 the height of each level of slope is 10m, and the width of the bench between slopes is 2m.

[0012] As a further optimization scheme of the present invention, the excavation strategy of the rock slope is shown in the following formula (2):

[0013]

[0014] In formula (2), the function g is the coupling algorithm of the excavation slope ratio and slope height of the rock slope; H is the slope height, with the unit of m; i is the excavation slope ratio of the slope; i 1 is the excavation slope ratio of the first-level slope, i 2 is the excavation slope ratio of the second-level slope, and so on; i 5+ is the excavation slope ratio of slopes above the fifth level.

[0015] As a further optimization scheme of the present invention, for the excavation strategies S 4 、S 5 and S 6 the height of each level of slope is 10m, and the width of the bench between slopes is 2m.

[0016] As a further optimization scheme of the present invention, for the soil slope, ecological revegetation + intercepting ditch + slope drainage ditch measures are adopted, and soil nails are used for support at easily collapsible parts.

[0017] As a further optimization scheme of the present invention, for the rock slope, natural moss greening is adopted, and shotcrete support is taken at locally broken parts.

[0018] The present invention also provides a system for implementing the slope excavation strategy and support method in the tropical rainforest area, which is characterized by including:

[0019] The soil slope excavation strategy module is used to construct the coupling algorithm of the excavation slope ratio and slope height of the soil slope to determine the excavation method of soil slopes with different heights;

[0020] The rock slope excavation strategy module is used to construct the coupling algorithm of the excavation slope ratio and slope height of the rock slope to determine the excavation method of rock slopes with different heights;

[0021] The slope excavation and support strategy construction module discriminates according to the geological conditions of the slope. If the discrimination result is a soil slope, it calls the soil slope excavation strategy module to carry out slope excavation design; if the discrimination result is a rock slope, it calls the rock slope excavation strategy module to carry out slope excavation design.

[0022] The slope excavation strategy, support method and system in the tropical rainforest area of the present invention have the following advantages and beneficial effects:

[0023] (1) The coupling algorithm of the excavation slope ratio and slope height for soil slopes and rock slopes proposed in the present invention is obtained based on engineering practice and sensitivity analysis. By calculating the stability coefficients of slopes with different heights and different excavation slope ratios, conclusions such as the negative correlation between slope height and safety factor in soil slopes, and the basically linear positive correlation between excavation slope ratio and safety factor are obtained, as well as similar relationships between height, slope ratio and safety factor in rock slopes. These conclusions provide a solid data basis for the algorithm, making the algorithm have a high reliability. Designers can directly draw on this algorithm, which provides a reference for quickly determining the excavation slope ratio of slopes, saving design time and cost, and avoiding repeated tests and calculations.

[0024] (2) A coupling algorithm of the excavation slope ratio and slope height for soil slopes and rock slopes applicable to the tropical rainforest area is established, which can determine the excavation methods of slopes with different heights. Whether it is a soil slope or a rock slope, and regardless of whether the slope height is from a few meters to dozens of meters or even more than one hundred meters, appropriate excavation and support plans can be quickly determined through the corresponding algorithms and strategies. For example, there are three excavation strategies, S1, S2, and S3, for soil slopes according to different heights, and three excavation strategies, S4, S5, and S6, for rock slopes. Each strategy specifies parameters such as the excavation slope ratio, height, and berm width of each level of the slope, realizing the rapid construction of excavation strategies and protection systems for any slope type and any slope height, providing clear guidance for construction and improving construction efficiency.

[0025] (3) For soil slopes, measures such as ecological restoration + intercepting ditch + slope drainage ditch are adopted. Ecological restoration helps to restore the slope ecological environment, and the intercepting ditch and slope drainage ditch can effectively prevent rainwater from scouring the slope surface and causing slope instability. At the same time, soil nails are used for support at easily collapsible parts, enhancing the stability of the soil slope. For rock slopes, natural moss greening is adopted, which conforms to the ecological characteristics of the tropical rainforest area. Shotcrete and bolting support are taken at locally broken parts, which can not only reinforce the broken parts to ensure slope safety, but also reduce the damage to the natural environment to a certain extent, achieving the balance between engineering construction and ecological protection.

[0026] (4) The slope excavation and support strategy proposed in this paper has been fully applied to the slope of the flood drainage ditch project of the Wawayme East Waste Dump in the Milado Copper Mine, Ecuador, saving approximately $3.05 million in project investment and about 6 months in construction period. This indicates that the invention has significant economic and social benefits, can reduce project costs, shorten the construction period, and improve the overall efficiency of project construction. Brief Description of the Drawings

[0027] Figure 1 It is a flowchart of the implementation of the slope excavation strategy and support method in the tropical rainforest area of the present invention. Detailed Implementation Modes

[0028] The following describes the detailed implementation modes of the present invention to facilitate those skilled in the art of this technology to understand the present invention. Obviously, the present invention is not limited to the scope of the detailed implementation modes.

[0029] As Figure 1 shown, the present invention proposes a slope excavation strategy and support method in the tropical rainforest area, including the following steps:

[0030] 1) Construct a soil slope excavation strategy

[0031] Based on the different heights and excavation slope ratios of the soil slope, calculate the stability coefficients of various excavation combined slopes, and obtain the following: ① The slope height is negatively correlated with the safety factor, and the excavation slope ratio is basically linearly positively correlated with the safety factor. ② When the slope height is less than 10m, the safety factors of the four excavation slope ratios of 1:1, 1:1.25, 1:1.5, and 1:1.75 are all greater than 1. ③ When the slope height is 10m - 25m, the safety factors of the three excavation slope ratios of 1:1.25, 1:1.5, and 1:1.75 are greater than 1, and the safety factor of the 1:1 excavation slope ratio is less than 1. ④ When the slope height is 25m - 50m, the safety factors of the three excavation slope ratios of 1:1.25, 1:1.5, and 1:1.75 are greater than 1, and the safety factor of the 1:1 excavation slope ratio is less than 1. ⑤ When the slope height is 50m - 75m, the safety factors of the two excavation slope ratios of 1:1.5 and 1:1.75 are greater than 1, and the safety factors of the two excavation slope ratios of 1:1 and 1:1.25 are less than 1. ⑥ When the slope height is greater than 75m, the safety factors of the two excavation slope ratios of 1:1.5 and 1:1.75 are greater than 1, and the safety factors of the two excavation slope ratios of 1:1 and 1:1.25 are less than 1. Based on the above analysis conclusions, construct a coupling algorithm for the excavation slope ratio and slope height of the soil slope to determine the excavation methods for slopes of different heights. As shown in Equation (1).

[0032]

[0033] In formula (1), the function f is the coupling algorithm of the excavation slope ratio and slope height of the soil slope, H is the slope height in m, and i is the excavation slope ratio of the slope. The excavation strategy S 1 : Applicable to soil slopes with a slope height H < 25m. The excavation slope ratio of the first level is 1:1, the excavation slope ratio of the second to third levels is 1:1.25, the height of each slope level is 10m, and the width of the berm between each slope is 2m. The excavation strategy S 2 : Applicable to soil slopes with a slope height of 25m ≤ H < 75m. The excavation slope ratio of the first to fifth levels is 1:1.25, the excavation slope ratio of the sixth to eighth levels is 1:1.5, the height of each slope level is 10m, and the width of the berm between each slope is 2m. The excavation strategy S 3 : Applicable to soil slopes with a slope height H ≥ 75m. The excavation slope ratio of the first to second levels is 1:1.25, the excavation slope ratio of the third to eighth levels is 1:1.5, and the excavation slope ratio of the slopes above the eighth level is 1:1.75. The height of each slope level is 10m, and the width of the berm between each slope is 2m.

[0034] 2) Construct the excavation strategy for rock slopes

[0035] Based on the different heights and different excavation slope ratios of rock slopes, calculate the stability coefficients of various excavated combined slopes, and obtain: ① The slope height and the safety factor are basically negatively correlated, and the excavation slope ratio and the safety factor are basically positively correlated. ② When the slope height is less than 50m, the safety factors of the slopes with four excavation slope ratios of 1:0.5, 1:0.75, 1:1, and 1:1.25 are all greater than 1. ③ When the slope height is 50m - 75m, the safety factors of the slopes with three excavation slope ratios of 1:0.75, 1:1, and 1:1.25 are not less than 1, and the safety factor of the slope with an excavation slope ratio of 1:0.5 is less than 1. ③ When the slope height is 75m - 100m, the safety factors of the slopes with three excavation slope ratios of 1:0.75, 1:1, and 1:1.25 are not less than 1, and the safety factor of the slope with an excavation slope ratio of 1:0.5 is less than 1. Based on the above analysis conclusions, construct the coupling algorithm of the excavation slope ratio and slope height of the rock slope, and determine the excavation methods for slopes of different heights. As shown in formula (2).

[0036]

[0037] In formula (2), the function g is the coupling algorithm of the excavation slope ratio and slope height of the rock slope, H is the slope height in m, and i is the excavation slope ratio of the slope. The excavation strategy S 4 : Applicable to rock slopes with a slope height H less than 50m. The excavation slope ratio of the first to fifth levels is 1:0.5, the height of each slope level is 10m, and the width of the berm between each slope is 2m. The excavation strategy S 5 : Applicable to rock slopes with a slope height of 50m ≤ H < 75m. The excavation slope ratio of the first to eighth levels is 1:0.75, the height of each slope level is 10m, and the width of the berm between each slope is 2m; The excavation strategy S6 : Applicable to rocky slopes with a slope height H≥75m. The excavation slope ratios for the 1st to 5th level slopes are 1:0.75, and for slopes above the 5th level are 1:1. The height of each slope level is 10m, and the width of the berm between each slope is 2m.

[0038] 3) Construct the slope excavation and support strategy

[0039] According to the slope geological conditions, if it is determined to be a soil slope, use S 1 excavation strategy for slope excavation design. If the final designed slope height H is less than 25m, then use S 1 excavation strategy for construction; otherwise, use S 2 excavation strategy for slope excavation design. If the final designed slope height 25m≤H<75m, then use S 2 excavation strategy for construction; otherwise, use S 3 excavation strategy for construction; to prevent slope instability caused by rainwater scouring the slope surface, for soil slopes, adopt ecological revegetation + intercepting ditch + slope drainage ditch measures, and use soil nails for support at easily collapsible parts. If it is determined to be a rocky slope, use S 4 excavation strategy for slope excavation design. If the final designed slope height H is less than 50m, then use S 4 excavation strategy for construction; otherwise, use S 5 excavation strategy for slope excavation design. If the final designed slope height 50m≤H<75m, then use S 5 excavation strategy for construction; otherwise, use S 6 excavation strategy for construction; for rocky slopes, adopt natural moss greening, and use shotcrete and bolting support for local broken parts.

[0040] The above strategy is applied comprehensively to the slopes of the flood drainage ditch project of the Wawayme East Waste Dump in the Mirador Copper Mine, Ecuador. The total length of the flood drainage ditch is 8.6 km, of which the soil slopes account for 71% and the rocky slopes account for 29%, distributed alternately. By using the above strategy, the slope excavation slope ratio can be determined quickly. By determining the reasonable excavation slope ratio, over-excavation and support work quantities are reduced, saving 3.05 million US dollars in project investment. By quickly determining the excavation slope ratio, work delays are reduced, saving about 6 months in the construction period.

[0041] In summary, for the slope excavation strategy, support method and system of the present invention in tropical rainforest areas, a coupling algorithm of excavation slope ratio and slope height for soil slopes and rocky slopes is established, realizing the rapid construction of excavation strategies and protection systems for slopes of any type and any height, providing guidance for slope construction in tropical rainforest areas, and saving project investment and shortening the construction period on the basis of ensuring slope safety.

[0042] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

[0043] The content not detailed in the description of the present invention belongs to the prior art well known to those skilled in the art.

Claims

1. A slope excavation strategy and support method in tropical rainforest areas, characterized in that: include: Construct soil slope excavation strategy: Construct a coupling algorithm between soil slope excavation ratio and slope height to determine the excavation methods for slopes of different heights; Construct rock slope excavation strategy: Construct a coupling algorithm between rock slope excavation ratio and slope height to determine the excavation methods for slopes of different heights; Construct slope excavation and support strategies: Based on the geological conditions of the slope, if it is determined to be an earth slope, the earth slope excavation strategy is used for slope excavation design; if it is determined to be a rock slope, the rock slope excavation strategy is used for slope excavation design.

2. The tropical rainforest slope excavation strategy and support method according to claim 1, characterized in that: The soil slope excavation strategy is shown in formula (1): In formula (1), function f is the coupling algorithm of soil slope excavation ratio and slope height; H is the slope height, unit is m; i is the slope excavation ratio; i1 is the first level slope excavation ratio, i2 is the second level slope excavation ratio, and so on; i 8+ It is the excavation slope ratio of slopes above level 8.

3. The tropical rainforest slope excavation strategy and support method according to claim 2, characterized in that: In excavation strategies S1, S2 and S3, the height of each slope is 10m and the width of the bridleway between the slopes is 2m.

4. The tropical rainforest slope excavation strategy and support method according to claim 1, characterized in that: The rock slope excavation strategy is shown in formula (2): In formula (2), function g is the coupling algorithm of rock slope excavation slope ratio and slope height; H is the slope height, unit is m; i is the slope excavation ratio; i1 is the first level slope excavation ratio, i2 is the second level slope excavation ratio, and so on; i 5+ It is the excavation slope ratio for slopes above level 5.

5. The tropical rainforest slope excavation strategy and support method according to claim 4, characterized in that: In excavation strategies S4, S5 and S6, the height of each slope is 10m and the width of the bridleway between the slopes is 2m.

6. The tropical rainforest slope excavation strategy and support method according to claim 1, characterized in that: For soil slopes, ecological restoration + intercepting ditches + slope drainage ditches are adopted, and soil nails are used to support the areas prone to collapse.

7. The tropical rainforest slope excavation strategy and support method according to claim 1, characterized in that: For rock slopes, natural moss greening is used, and sprayed anchor support is used in locally broken areas.

8. A system for executing the tropical rainforest slope excavation strategy and support method as claimed in claim 1, characterized in that: include: The soil slope excavation strategy module is used to construct an algorithm for coupling soil slope excavation ratio with slope height to determine the excavation methods for soil slopes of different heights. The rock slope excavation strategy module is used to construct a coupling algorithm between the rock slope excavation ratio and the slope height to determine the excavation methods for rock slopes of different heights; The slope excavation and support strategy construction module makes a judgment based on the geological conditions of the slope. If the judgment result is a soil slope, the soil slope excavation strategy module is called to perform slope excavation design; if the judgment result is a rock slope, the rock slope excavation strategy module is called to perform slope excavation design.

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