A method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides.

Abstract

This invention belongs to the field of rockfall protection technology and discloses a method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides. It addresses the problems of poor effectiveness and high cost of existing protection systems for such formations. Based on known data and information, this invention designs and calculates a method to gradually dissipate energy from landslides by rationally setting up energy dissipation zones (i.e., at least one buffer zone), buffer zones, and retaining zones, thereby effectively controlling steep, dangerous rock formations and large-scale landslides. Furthermore, the energy dissipation structure of this invention uses locally sourced materials, is easy to construct, and requires no large-scale engineering equipment. It solves the problem of disaster prevention measures for steep, dangerous rock formations and large-scale landslides, providing a scientific, effective, and safe prevention measure, promoting the standardization of disaster prevention for such formations, and featuring low construction costs and a short construction period.

Description

Technical Field

[0001] This invention belongs to the field of rockfall protection and treatment technology, specifically relating to a method for protecting and dissipating energy from steep, dangerous rocks and large-scale landslides, used for energy dissipation treatment of steep, dangerous rocks (with a drop of more than 300m) and large-scale landslides (with a volume of more than 10,000 cubic meters). Background Technology

[0002] my country is a mountainous country, with mountains covering approximately two-thirds of its total area. Particularly affected by the strong uplift of the Qinghai-Tibet Plateau, southwestern my country is characterized by its numerous high mountains and deep valleys, intense tectonic activity, extremely uneven rainfall, high ground stress, and frequent earthquakes, making it a high-risk area for landslides. High-altitude, steep rockfalls are characterized by uncertainty, randomness, suddenness, concealment, and strong destructive power. For example, in 2001, a high-cut landslide occurred in Wulong County, with a height difference of 300-400 meters; in 2003, the Pingxi Grand Bridge in Sansui collapsed, with an unstable volume of approximately 200,000 cubic meters. 3 In 2007, a landslide occurred on National Highway 319 in Pengshui County, creating a gap of over 30 meters. More than 5,000 tons of boulders smashed the road surface and foundation onto a steep slope downstream of the highway and into the Wujiang River, causing a one-month interruption of fiber optic cables. In 2017, the Jiuzhaigou earthquake caused dozens of large landslides, severely impacting the safe operation of the Jiuzhaigou scenic area. In 2019, a landslide on the Chengdu-Kunming Railway caused the suspension of passenger train services between Chengdu and Xichang. In September 2021, a high-altitude landslide occurred at the entrance of the Xier Tunnel on National Highway 347 (Maohong Road), with a total landslide area of ​​approximately 10,000 square meters. 2 The total volume is approximately 4000 m³. 3 The rocks rapidly collapsed from the steep slope and accumulated above and around the tunnel entrance. The falling rocks hit and damaged the brick structure of the tunnel entrance and buildings near the tunnel entrance, causing serious damage to the tunnel construction team's camp.

[0003] Therefore, high-altitude landslides cause severe geological disasters, resulting in painful lessons, causing varying degrees of casualties and property losses, and seriously affecting the safe construction and operation of railways, highways, towns, and mines in mountainous areas of my country. The serious disasters and significant losses caused by them cannot be ignored. Therefore, in-depth research on methods for preventing and controlling high and steep rock collapses is an urgent need for the safety of engineering construction and operation, and has important theoretical research significance and engineering application value.

[0004] Existing technologies also include technical literature on rockfall protection, such as patent CN106400709B, which discloses a prefabricated rubber energy dissipation plate protective structure for preventing rockfalls on the roof of a tunnel. This protective structure consists of energy dissipation blocks, multiple of which are connected to form an energy dissipation plate, which is fixed to the top of the tunnel. A waterproof layer is provided between the energy dissipation plate and the tunnel roof. The energy dissipation blocks are made of rubber material. This patent utilizes the plasticity and ease of assembly of rubber material, greatly reducing construction difficulty and cost. Rubber material has good buffering and energy dissipation characteristics under impact loads, increasing the impact duration of falling rocks on the tunnel roof, thereby effectively reducing the impact force of falling rocks. However, this patent mainly improves the buffer layer of the tunnel and does not provide systematic protection for dangerous rocks. The engineering treatment cost is high, the application scope and protection range are limited, and the protection capability for steep dangerous rocks (drop greater than 300m or large-scale collapse rock and soil masses with a collapse volume of more than 10,000 square meters) is extremely weak.

[0005] For example, patent CN 107268467 A discloses a rockfall interception structure, including a first-level protective net and a second-level protective net. The first-level protective net is equipped with a first-level protective brace, and the second-level protective net is equipped with a second-level protective brace. This patent can protect against general unstable rocks or sporadic falling rocks through the protective net and protective brace, but it is less effective than the protection against high-level unstable rocks and large-scale rock and soil collapses, and the subsequent cleanup is difficult. Summary of the Invention

[0006] To address the problems of poor protection effectiveness and high cost of existing protection systems for steep, dangerous rocks and large-scale landslides, this invention provides a method for energy dissipation and protection of steep, dangerous rocks and large-scale landslides. This method can quickly and reliably complete the prestress testing of anti-buoyancy anchors, filling the gap in the prestress testing of anti-buoyancy anchors.

[0007] To solve the technical problem, the technical solution adopted by this invention is as follows:

[0008] A method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides is provided, characterized by including an energy dissipation system and an energy dissipation method based on the system, comprising:

[0009] (1) Based on on-site investigation and survey data, information on steep and dangerous rocks and large collapsed rock and soil masses is obtained. The information includes, but is not limited to, the collapse height H of the collapsed body, the volume of the collapsed body, the maximum gravel diameter D of the collapsed body, the weight G of the maximum gravel diameter, and the initial velocity v of the collapsed body when it detaches from the parent body. i The extent of the landslide, the slope angle α, and the resistance coefficient K of the falling rock mass;

[0010] (2) Calculate the falling time □t of the collapsed body according to the following formula:

[0011] ,

[0012] Among them, v iy For v i The vertical component, v ix For v i The horizontal component;

[0013] (3) The first landing velocity v of the collapsed body is obtained according to the following two formulas. （i+1） v （i+1）x、 v （i+1）y x i+1 y i+1 , where v （i+1）y The initial landing speed v （i+1） The vertical component, v （i+1）x The initial landing speed v （i+1） The horizontal component, x i+1 y represents the horizontal displacement of the collapsed body upon first impact. i+1 This represents the vertical displacement of the collapsed body upon first impact.

[0014]

[0015] ,

[0016] Where x i y represents the horizontal distance from the landslide body to the top of the hillside. i The value is 0;

[0017] (4) The instantaneous kinetic energy of the collapsed body before its first impact is obtained according to the following formula:

[0018] ;

[0019] (5) The depth Z of the collapse body with the largest gravel diameter that contacts and sinks into the buffer layer of the energy dissipation structure of the energy dissipation system when it first lands is calculated using the following two formulas. The energy dissipation structure includes a buffer layer, which includes a fine sand layer and a foam board located below the fine sand layer. The ratio of the thickness of the foam board to the thickness of the fine sand layer is 1:2. The unit density γ of the buffer layer and the internal friction angle of the buffer layer are determined based on the materials of the foam board and the fine sand. φ and the uniform compressibility coefficient of the buffer layer c u：

[0020] ;

[0021] (6) Calculate the energy W absorbed by the buffer layer of the energy dissipation structure when the collapsed body first hits the ground using the following formula.e :

[0022] ;

[0023] (7) The velocity V of the collapse body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure is obtained by using two formulas. ei ;

[0024] ,

[0025] Where P max denoted as , where is the maximum impact force when the largest gravel diameter lands on the ground for the first time, and m is the mass of the largest gravel diameter.

[0026] (8) The velocity V of the collapsed body with the largest gravel diameter obtained in step (7) after colliding with the buffer layer of the first-stage energy dissipation structure. ei The bounce height H of the collapsed body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure was calculated. max If H max If H ≤ 1.0m, it indicates that the buffer layer of the first-stage energy dissipation structure set at the first landing point of the collapsed body meets the requirements; if H max If the height is greater than 1.0m, the number of energy dissipation stages needs to be increased until H... max No more than 1.0m.

[0027] In some embodiments, if the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, the thickness of the buffer layer is designed to be 1.5m, and Z = Zs = 1.5m, and a multi-stage energy dissipation structure is added.

[0028] In some embodiments, if the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, then the thickness of the buffer layer is designed to be 1.5m, where Z = 1.5m, and a multi-stage energy dissipation structure is added; and the Z value in step (6) is taken as 1.5m, and V is calculated in step (7). ei The Z value in the formula is taken as 1.5m.

[0029] In some embodiments, the energy dissipation structure further includes a gabion retaining wall set on the hillside, with vertical reinforcing bars spaced apart inside the gabion retaining wall and the vertical reinforcing bars connected to each other. The buffer layer is placed on the upper layer between the hillside and the gabion retaining wall. Multiple layers of steel-plastic grids are spaced apart along the height direction of the hillside on the hillside below the buffer layer. Anchor rods are also spaced apart inside the hillside below the buffer layer. The steel-plastic grids and anchor rods are arranged alternately. One end of the anchor rod is inserted into the hillside, and the other end of the anchor rod is connected to the gabion retaining wall.

[0030] In some embodiments, the slope surface below the energy dissipation structure is used as a buffer zone by utilizing trees on the slope or by implanting small-diameter steel pipe piles.

[0031] In some embodiments, a rockfall trough is provided at the bottom of the hillside, and a passive protective net is provided on the side of the rockfall trough away from the hillside to form a retaining area.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The energy dissipation method for protecting steep, unstable rock formations and large-scale landslides of this invention provides detailed on-site investigations and surveys for steep, unstable rock formations (with a drop of over 300m) and large-scale landslides (with an earthwork volume of over 10,000 square meters). Generally, the survey and design are completed by a single construction team, ensuring comprehensive data on steep, unstable rock formations and large-scale landslides. This data includes, but is not limited to, the collapse height H, the earthwork volume of the landslide, the maximum gravel diameter D, the weight G of the maximum gravel diameter, and the initial velocity v of the landslide when it detaches from the parent rock. i The extent of the landslide, the slope angle α, the resistance coefficient of the falling rock mass K, and the horizontal distance x from the top of the slope to the landslide body. i Therefore, this invention, based on known information, designs and calculates to gradually dissipate energy from landslides by rationally setting up energy dissipation zones (i.e., at least one level of buffer zone), buffer zones, and retaining zones, thereby effectively controlling steep, dangerous rock formations and large-scale landslides. Furthermore, the energy dissipation structure of this invention uses locally sourced materials, is easy to construct, and requires no large-scale engineering equipment, thus solving the problem of disaster prevention measures for steep, dangerous rock formations and large-scale landslides. It provides a scientific, effective, and safe prevention measure for such formations, promotes the standardization of disaster prevention for steep, dangerous rock formations and large-scale landslides, and features low construction costs and a short construction period. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of an embodiment of the energy dissipation system of the present invention. In this schematic diagram, the energy dissipation system includes a first-stage energy dissipation structure and a second-stage energy dissipation structure.

[0035] Figure 2 This is a schematic diagram illustrating the motion analysis of the collapsed body according to the present invention;

[0036] Figure 3 This is a schematic diagram of the energy dissipation structure of the present invention;

[0037] The markings in the diagram are: 01, landslide body; 02, trajectory of landslide body; 03, hillside; 04, highway; 05, building; 1, energy dissipation zone; 101, first-level energy dissipation structure; 11, buffer layer; 12, gabion retaining wall; 13, steel-plastic grid; 14, anchor bolt; 102, second-level energy dissipation structure; 2, buffer zone; 3, retaining zone. Detailed Implementation

[0038] The present invention will be further described below with reference to embodiments. These embodiments are merely some, not all, of the embodiments of the present invention. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the protection scope of the present invention.

[0039] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention in conjunction with the specific circumstances.

[0040] As stated in the background section of this application, current methods for protecting dangerous rocks, such as active protection (i.e., surrounding the dangerous area with protective netting) and passive protection (setting up protective netting on the slope surface and toe), are insufficient to effectively protect against steep, unstable rock formations and large-scale landslides, resulting in serious threats to people's lives and property. Furthermore, existing protective measures generally suffer from high construction costs and long construction periods, and are inseparable from the use of large-scale engineering equipment. Based on these technical problems, this invention provides a method for protecting and dissipating energy from steep, unstable rock formations and large-scale landslides.

[0041] Referring to the accompanying drawings, the energy dissipation method for protecting and dissipating high and steep dangerous rocks and large-scale landslide rock and soil masses of the present invention is used for protecting and dissipating energy from high and steep dangerous rocks and large-scale landslide rock and soil masses, including an energy dissipation system, and an energy dissipation method based on the energy dissipation system including:

[0042] (1) Based on on-site investigation and survey data, information on steep and dangerous rocks and large collapsed rock and soil masses is obtained. The information includes, but is not limited to, the collapse height H (m), the volume of earthwork of the collapsed body, the maximum gravel diameter D (m), the weight G of the maximum gravel diameter, and the initial velocity v of the collapsed body when it detaches from the parent body. i The data includes (m / s), the extent of the landslide, the slope angle α (°), and the resistance coefficient K of the falling rock mass. These data can be known in advance through surveying and measurement, and are understood by those skilled in the art, so they will not be elaborated here. Among them, the maximum gravel diameter of the landslide refers to the largest rock mass in the landslide. Generally, after the landslide, the rock mass will disintegrate under the action of huge impact force (that is, the various rock masses connected by soil will separate from each other under the action of impact force). Since the largest rock mass in the landslide is the most dangerous, this invention mainly studies the rock mass with the largest gravel diameter in the landslide.

[0043] (2) The falling time □t (s) of the collapsed body is calculated according to the following formula:

[0044] ,

[0045] Among them, v iy For v i The vertical component, v ix For v i The horizontal component.

[0046] (3) The first landing velocity v of the collapsed body is obtained according to the following two formulas. （i+1） v （i+1）x、 v （i+1）y x i+1 y i+1 , where v （i+1）y The initial landing speed v （i+1） The vertical component, v （i+1）x The initial landing speed v （i+1） The horizontal component, x i+1 y represents the horizontal displacement (m) of the collapsed body upon first impact. i+1 The vertical displacement (m) of the collapsed body when it first hits the ground.

[0047]

[0048] ;

[0049] Where x i y is the horizontal distance from the collapsed body to the top of the slope at point 03. i The value is 0. In this step, v （i+1） It refers to the instantaneous velocity of the collapsed body before it comes into contact with the buffer layer.

[0050] In reality, due to the extremely high falling speed of steep, unstable rocks and large landslides, the influence of the drag coefficient K is almost negligible. Therefore, y i+1 It equals H.

[0051] To ensure that the energy dissipation structure of the energy dissipation system can withstand the collapsed material, the width of the buffer layer 11 along the X-axis is x. i+1 +5m, to ensure that the buffer layer 11 can accommodate landslides at different heights (in fact, through the survey by technicians, it is basically possible to determine which rock masses are high-risk or landslide masses; therefore, to improve safety, the width of the buffer layer is designed to be x). i+1 +5m). Of course, construction workers can also adjust the width of the buffer layer 11 along the X-axis direction according to specific circumstances, for example, to x i+1 +2m、x i+1 +4m, x i+1 +6m, etc., are things that those skilled in the art can understand and comprehend, so I will not go into detail here.

[0052] (4) The instantaneous kinetic energy of the collapsed body before its first impact is obtained according to the following formula:

[0053] .

[0054] (5) The depth Z of the first impact of the landslide body with the maximum gravel diameter, which contacts and sinks into the buffer layer of the energy dissipation structure of the energy dissipation system, is calculated using the following two formulas. The energy dissipation structure includes the buffer layer 11, and the multi-level energy dissipation structure together constitutes the energy dissipation zone 1 (e.g., attached). Figure 1 The first-stage energy dissipation structure 101 and the second-stage energy dissipation structure 102 shown in the figure constitute the energy dissipation zone 1). The buffer layer 11 includes a fine sand layer and a foam board located below the fine sand layer. The thickness ratio of the foam board to the fine sand layer is 1:2. The unit density γ and the internal friction angle of the buffer layer are determined based on the materials of the foam board and the fine sand. φ and the uniform compressibility coefficient of the buffer layer c u：

[0055] ,

[0056] Where A represents the contact area between the collapsed body and the buffer layer.

[0057] (6) Calculate the energy W absorbed by the buffer layer of the energy dissipation structure when the collapsed body first hits the ground using the following formula. e :

[0058] .

[0059] (7) The velocity V of the collapse body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure is obtained by using two formulas. ei ;

[0060] ,

[0061] Among them, P max G represents the maximum impact force when the largest gravel diameter lands on the ground for the first time, and m represents the mass of the largest gravel diameter. G = mg, which is clear and understandable to those skilled in the art and will not be elaborated further here.

[0062] Among them, the maximum impact force P max A reference for the structural strength of energy dissipation structures, to ensure that the energy dissipation structures withstand the maximum impact force P. max Under the action of the energy dissipation structure, the stability of the energy dissipation structure can be maintained (i.e., the structure of gabion retaining wall 12, steel-plastic grid 13 and anchor rod 14 is stable).

[0063] (8) The velocity V of the collapsed body with the largest gravel diameter obtained in step (7) after colliding with the buffer layer of the first-stage energy dissipation structure. ei The bounce height H of the collapsed body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure was calculated. max If H max If H ≤ 1.0m, it indicates that the buffer layer of the first-stage energy dissipation structure set at the first landing point of the collapsed body meets the requirements; if H max If the height is greater than 1.0m, the number of energy dissipation stages needs to be increased until H... max Not greater than 1.0m. Where H max For heights greater than 1.0m, a multi-stage energy dissipation structure is required. For example, see attached... Figure 1 The energy dissipation zone 1 shown in the image includes a first-stage energy dissipation structure 101 and a second-stage energy dissipation structure 102.

[0064] When V is obtained using the formula in step (7) ei After obtaining the data (including velocity and direction), the trajectory of the collapsed body after its bounce can be determined using the basic formula of a kinematic parabola. This allows us to determine the height and horizontal distance of the collapsed body. Combined with the slope angle of hillside 03, the location of the second-stage energy dissipation structure can be calculated. The calculation process is the same as that between the fall of collapsed body 01 and the first-stage energy dissipation structure, and will not be repeated here.

[0065] Such as jump height Hmax (m) can be calculated using the following formula:

[0066] , where θ is V ei The angle between the direction of motion and the horizontal direction.

[0067] In some embodiments, if the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, the thickness of the buffer layer is designed to be 1.5m, where Z = 1.5m, and a multi-stage energy dissipation structure is added.

[0068] In some embodiments, if the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, then the thickness of the buffer layer is designed to be 1.5m, where Z = 1.5m, and a multi-stage energy dissipation structure is added; and the Z value in step (6) is taken as 1.5m, and V is calculated in step (7). ei The Z value in the formula is taken as 1.5m. Based on engineering experience, when the thickness of the buffer layer 11 is greater than 1.5m, the buffering efficiency of the buffer layer is not significant as the thickness of the buffer layer increases. Therefore, when the calculated Z value depth is greater than 1.5m, the buffer layer 11 is designed according to 1.5m, and the number of energy dissipation stages is increased.

[0069] That is to say, when the calculated depth Z of the buffer layer 11 is greater than 1.5m or the calculated H max When the height is greater than 1m, a multi-stage energy dissipation structure needs to be designed to reduce the destructive force of the collapse and keep it within an acceptable (or controllable) range.

[0070] In some embodiments, the energy dissipation structure further includes a gabion retaining wall 12 disposed on the hillside 03. Vertical reinforcing bars are spaced apart within the gabion retaining wall 12 and are connected to each other. The buffer layer 11 is placed on the upper layer between the hillside 03 and the gabion retaining wall 12. Multiple layers of steel-plastic grids 13 are spaced apart along the height direction of the hillside 03 below the buffer layer 11. Anchor rods 14 are also spaced apart within the hillside 03 below the buffer layer 11. The steel-plastic grids 13 and anchor rods 14 are arranged alternately. One end of the anchor rod 14 is inserted into the hillside 03, and the other end of the anchor rod 14 is connected to the gabion retaining wall 12.

[0071] In practical implementation, gabion retaining walls can use gabion cages with a cross-sectional dimension of 2×1×1m, which have better mechanical properties than the gabions in the EN10223-3 standard. To improve the integrity of the gabion cages, vertical reinforcing bars are installed between them (for example, the diameter of the vertical reinforcing bars is 32mm, the length of the vertical reinforcing bars is 60cm, and the spacing of the vertical reinforcing bars is 20cm). The materials inside the gabion cages can be sourced locally. The spacing of the steel-plastic grating 13 is 1.0m. The steel-plastic grating is mainly made of cold-drawn carbon spring steel wire, polyethylene and other high molecular polymers, with a certain amount of anti-ultraviolet and anti-aging additives and other reinforcing and modifying substances added. It is integrally formed by extrusion and composite steel-plastic composite strips in the warp and weft directions.

[0072] The anchor rods are inserted into the hillside to a depth of at least 3m and then connected to the gabion retaining wall 12 by connecting steel bars.

[0073] In some embodiments, the slope 03 below the energy dissipation structure utilizes trees on the slope or small-diameter steel pipe piles as a buffer zone 2. In specific implementation, the small-diameter steel pipe piles are 5.0m long, embedded 2.5m into the slope, 130mm in diameter, and spaced 3m x 3m apart. This utilizes existing trees on slope 03 or the implanted steel pipe piles to impede the falling speed of the landslide body 01, thereby reducing the speed at which the landslide body 01 falls to the bottom of slope 03 to essentially zero.

[0074] In some embodiments, a rockfall trough 31 is provided at the bottom of the hillside, and a passive protective net 32 ​​is provided on the side of the rockfall trough 31 away from the hillside 03 to form a barrier zone 3, thereby protecting the road 04 and buildings 05 at the bottom of the hillside 03.

[0075] The energy dissipation method for protecting steep, unstable rock formations and large-scale landslides of this invention provides detailed on-site surveys and investigations for steep, unstable rock formations (with a drop of over 300m) and large-scale landslides (with an earthwork volume of over 10,000 square meters). Generally, the investigation and design are completed by a single construction team, ensuring comprehensive data on steep, unstable rock formations and large-scale landslides. This data includes, but is not limited to, the collapse height H, the earthwork volume of the landslide, the maximum gravel diameter D, the weight G of the maximum gravel diameter, and the initial velocity v of the landslide when it detaches from the parent rock. i The extent of the landslide, the slope angle α, the resistance coefficient of the falling rock mass K, and the horizontal distance x from the top of the slope to the landslide body. iTherefore, this invention, based on known information, designs and calculates to gradually dissipate energy from landslides by rationally setting up energy dissipation zones (i.e., at least one level of buffer zone), buffer zones, and retaining zones, thereby effectively controlling steep, dangerous rock formations and large-scale landslides. Furthermore, the energy dissipation structure of this invention uses locally sourced materials, is easy to construct, and requires no large-scale engineering equipment, thus solving the problem of disaster prevention measures for steep, dangerous rock formations and large-scale landslides. It provides a scientific, effective, and safe prevention measure for such formations, promotes the standardization of disaster prevention for steep, dangerous rock formations and large-scale landslides, and features low construction costs and a short construction period.

Claims

1. A method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides, characterized in that, This includes energy dissipation systems, and energy dissipation methods based on these systems include: (1) Based on on-site investigation and survey data, information on high and steep dangerous rocks and large collapsed rock and soil masses is obtained. The information includes, but is not limited to, the collapse height H of the collapsed body, the volume of the collapsed body, the maximum gravel diameter D of the collapsed body, the weight G of the maximum gravel diameter, and the initial velocity v of the collapsed body when it detaches from the parent body. i The extent of the landslide, the slope angle α, and the resistance coefficient K of the falling rock mass; (2) Calculate the falling time □t of the collapsed body according to the following formula: ， Among them, v iy For v i The vertical component, v ix For v i The horizontal component; (3) The first landing velocity v of the collapsed body is obtained according to the following two formulas. （i+1） v （i+1）x、 v （i+1）y x i+1 y i+1 , where v （i+1）y The initial landing speed v （i+1） The vertical component, v （i+1）x The initial landing speed v （i+1） The horizontal component, x i+1 y represents the horizontal displacement of the collapsed body upon first impact. i+1 This represents the vertical displacement of the collapsed body upon first impact. ， Where x i y represents the horizontal distance from the landslide body to the top of the hillside. i The value is 0; (4) The instantaneous kinetic energy of the collapsed body before its first impact is obtained according to the following formula: ； (5) The depth Z of the collapse body with the largest gravel diameter that contacts and sinks into the buffer layer of the energy dissipation structure of the energy dissipation system when it first lands is calculated using the following two formulas. The energy dissipation structure includes a buffer layer, which includes a fine sand layer and a foam board located below the fine sand layer. The ratio of the thickness of the foam board to the thickness of the fine sand layer is 1:

2. The unit density γ of the buffer layer and the internal friction angle of the buffer layer are determined based on the materials of the foam board and the fine sand. φ and the uniform compressibility coefficient of the buffer layer c u： ； Where A represents the contact area between the collapsed body and the buffer layer; (6) Calculate the energy W absorbed by the buffer layer of the energy dissipation structure when the collapsed body first hits the ground using the following formula. e : ； (7) The velocity V of the collapse body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure is obtained by using two formulas. ei ; ； Among them, P max denoted as , where is the maximum impact force when the largest gravel diameter lands on the ground for the first time, and m is the mass of the largest gravel diameter. (8) The velocity V of the collapsed body with the largest gravel diameter obtained in step (7) after colliding with the buffer layer of the first-stage energy dissipation structure. ei The bounce height H of the collapsed body with the largest gravel diameter after colliding with the buffer layer of the first-stage energy dissipation structure was calculated. max If H max If H ≤ 1.0m, it indicates that the buffer layer of the first-stage energy dissipation structure set at the first landing point of the collapsed body meets the requirements; if H max If the height is greater than 1.0m, the number of energy dissipation stages needs to be increased until H... max Not greater than 1.0m; , where θ is V ei The angle between the direction of motion and the horizontal direction.

2. The method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides according to claim 1, characterized in that, If the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, then the thickness of the buffer layer is designed to be 1.5m, Z = 1.5m, and a multi-stage energy dissipation structure is added.

3. The method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides according to claim 1, characterized in that, If the maximum gravel diameter of the collapsed body calculated in step (5) contacts the buffer layer of the energy dissipation structure and sinks into the buffer layer to a depth Z greater than 1.5m when it first lands, then the thickness of the buffer layer is designed to be 1.5m, where Z = 1.5m, and a multi-stage energy dissipation structure is added; and the Z value in step (6) is taken as 1.5m, and the V value in step (7) is calculated. ei The Z value in the formula is taken as 1.5m.

4. The method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides according to claim 1, characterized in that, The energy dissipation structure also includes a gabion retaining wall set on the hillside. Vertical reinforcing bars are spaced apart inside the gabion retaining wall and are connected to each other. The buffer layer is placed on the upper layer between the hillside and the gabion retaining wall. Multiple layers of steel-plastic grids are spaced apart along the height direction of the hillside on the hillside below the buffer layer. Anchor rods are also spaced apart inside the hillside below the buffer layer. The steel-plastic grids and anchor rods are arranged alternately. One end of the anchor rod is inserted into the hillside, and the other end of the anchor rod is connected to the gabion retaining wall.

5. The method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides according to claim 1, characterized in that, The slope surface below the energy dissipation structure can be used as a buffer zone by utilizing trees on the slope or by implanting small-diameter steel pipe piles.

6. The method for protecting and dissipating energy from steep, dangerous rock formations and large-scale landslides according to claim 1, characterized in that, A rockfall trough is provided at the bottom of the hillside, and a passive protective net is installed on the side of the rockfall trough away from the hillside to form a barrier zone.

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