Treatment method for wedge-shaped landslide
Patent Information
- Application Number
- CN202411874367.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-02-14
Smart Images
Figure CN119434299A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of landslide control, in particular to a control method for wedge-shaped landslide. Background Art
[0002] At present, the sliding failure mode of most landslides belongs to plane sliding, and the sliding surface is mainly controlled by weak interlayers. The design and treatment plan usually adopts strong support measures such as anti-slide piles or anchor piles. The depth of the sliding surface of this type of landslide can be found out through conventional methods such as geological drilling and in-hole photography. Based on the material composition of the landslide body found out by investigation and the sliding surface parameters determined by indoor tests, the residual sliding force of the landslide can be calculated using conventional geotechnical design software. According to the residual sliding force, the diameter, spacing, reinforcement and anchor cable design of the anti-slide piles can be determined.
[0003] In addition to the above-mentioned landslides caused by plane sliding, there is another type of landslide whose failure form is wedge sliding. There are relatively few studies on this type of wedge landslide and in engineering practice, mainly due to factors such as special tectonic movements in geological history and later human engineering activities. A very obvious feature of wedge landslides is the existence of syncline structures, which are natural and good water storage structures. Under the action of rainfall, rainwater directly enters the landslide body and infiltrates into the syncline groove at the sliding surface. As more and more rainwater is collected, the water in the syncline groove at the sliding surface has pressure-bearing characteristics, which has a supporting effect on the landslide body above the sliding surface. Under the dual effects of the sliding force in the landslide body and the support of the pressurized water, the wedge landslide produces sliding deformation. From the above analysis, it can be seen that the deformation and failure mechanisms of wedge-shaped landslides and plane sliding landslides are obviously different. First, due to the existence of syncline structure, the pressurized water in the syncline trough of the wedge-shaped landslide has a supporting effect on the landslide body, while the plane sliding landslide generally does not have such a supporting effect; second, the sliding surface of the plane sliding landslide is two-dimensional in spatial distribution, while the sliding surface of the wedge-shaped landslide is three-dimensional in spatial distribution, which is more complicated.
[0004] At present, there are relatively few studies and engineering practices on wedge-shaped landslides. Most of the engineering practices follow the landslide support form of the plane sliding failure mode, and roughly adopt strong support measures such as multiple rows of large-diameter anti-sliding piles or anchor piles for control design, without combing the groundwater. This often leads to overly conservative support design schemes and increased engineering investment. Some even fail to really understand the calculation method of the residual sliding force when calculating the residual sliding force. The design value of the residual sliding force is too low, resulting in the support design scheme being too aggressive, failing to effectively control the landslide, posing a huge safety hazard and posing a huge threat to people's lives and property. Summary of the invention
[0005] The present invention provides a method for treating wedge-shaped landslides, aiming to solve the rough design mode of using strong support measures such as multiple rows of large-diameter anti-slide piles or anchor piles, so as to reduce the project cost while ensuring safety.
[0006] The present invention provides the following technical solutions to achieve the above objectives:
[0007] A method for treating a wedge-shaped landslide comprises the following steps:
[0008] Step 1: According to the size and shape of the landslide, set up a drainage ditch around the landslide;
[0009] Step 2: A foot retaining wall is set up along the boundary line of the landslide body at the front edge of the landslide body, and a drainage ditch is set up at the front edge of the foot retaining wall;
[0010] Step 3: excavate drainage corridors along the length direction of the oblique core of the landslide body and within the slide bed;
[0011] Step 4: Install a row of embedded anti-slide piles perpendicular to the length direction of the syncline core at the position of half of the maximum residual sliding force of the landslide body;
[0012] Step 5: Set a row of anchor piles perpendicular to the length direction of the syncline core at one-third of the maximum residual sliding force of the landslide body.
[0013] Furthermore, the drainage ditch is connected to the intercepting ditch.
[0014] Furthermore, the drainage corridor is arranged within a range of 5 to 8 meters below the sliding surface, and the centerline of the drainage corridor is in the same plane as the centerline of the syncline core. The inlet end of the drainage corridor is selected according to the actual project situation, the end of the drainage corridor is set flush with the rear edge of the landslide body, and the longitudinal section of the drainage corridor is set with a longitudinal slope of 5‰. The cross-section of the drainage corridor is in the shape of an arch, and the arch part of the drainage corridor is evenly arranged with drainage holes along the length direction of the drainage corridor. The end of the drainage hole away from the drainage corridor is set in the syncline trough, and a drainage blind pipe is set in the drainage hole; the direction of the drainage hole is set perpendicular to the arc of the arch part.
[0015] Furthermore, a side ditch is arranged on the bottom plate of the drainage corridor along the length direction of the drainage corridor.
[0016] Furthermore, the length of the bottom end of the embedded anti-slip pile embedded in the sliding surface accounts for one third of the total pile length.
[0017] Furthermore, the pile heads of the anchor piles are extended out of the ground, and the pile heads of the anchor piles are connected to each other through a crown beam, a prestressed anchor cable is arranged on the crown beam, and one end of the prestressed anchor cable away from the crown beam is anchored below the bottom boundary of the landslide body.
[0018] Beneficial Effects
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] The present invention sets a drainage gallery to drain the water in the chute into the gallery through drainage holes, thereby lowering the groundwater level in the chute to near the sliding surface, reducing the supporting force of the groundwater in the chute on the landslide body, and increasing the stability of the landslide body.
[0021] The purpose of setting up anchor piles and buried anti-slide piles is to share the remaining sliding force of the entire landslide, which can reduce the pile diameter and reinforcement of the anti-slide piles, while increasing the spacing between the anti-slide piles, in order to achieve the purpose of economic savings while ensuring safety. The reason why buried anti-slide piles are set up as buried is that, first, they can play an anti-slide role and share the remaining sliding force, and second, they are more economical and reduce the project cost compared to the anti-slide pile design that extends out of the ground. The purpose of setting up the anchor structure for the front row of anchor piles is that, first, it can control the horizontal displacement of the anti-slide piles, and second, the prestressed anchor cables can reinforce the landslide. The main function of setting up the crown beam for the front row of anti-slide piles is to increase the overall stability of the anti-slide piles;
[0022] The purpose of setting up the retaining wall is to support the area from the anti-slide piles to the front edge of the landslide body, ensuring the safety and stability of the landslide body in this area. The reason why anti-slide piles are no longer set up in this area is that the construction cost of the retaining wall is cheaper than that of the anti-slide piles, which can reduce the project cost; secondly, the residual sliding force in this area is small, and ordinary retaining walls can meet the design requirements;
[0023] Set up intercepting ditches to collect and drain surface water outside the landslide body, preventing it from entering the landslide body and threatening the stability of the landslide;
[0024] The purpose of setting up drainage ditches is to collect and drain the water in the landslide body;
[0025] Through the above engineering structure, a method for treating wedge-shaped landslide is formed; through the above content, it is known that under the dual effects of the sliding force in the landslide body and the top support of the pressurized water, the landslide produces sliding deformation, and the setting of the drainage corridor can reduce the top support of the groundwater in the skew trough on the landslide body, and increase the stability of the landslide body; the setting of the front row of anchor piles, the rear row of embedded anti-slide piles and the foot retaining wall can offset the sliding force in the landslide body; the interception and drainage measures can eliminate the hidden danger of the surface water outside the landslide body entering the landslide body. The support system involved in the present invention has mature construction technology, there is no special construction process, the raw materials involved can be purchased on the market, and the required mechanical equipment is also conventional construction equipment, which has great application and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below only relate to some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.
[0027] Figure 1 This is a schematic diagram of the plan layout of landslide treatment according to the present invention;
[0028] Figure 2 This is a cross-sectional view of the landslide treatment of the present invention;
[0029] Figure 3 This is a cross-sectional view of the drainage gallery support of the present invention;
[0030] Figure numerals: 1- intercepting ditch; 2- rear edge of landslide; 3- drainage ditch; 4- drainage hole; 5- embedded anti-slide pile; 6- anchor pile; 7- foot retaining wall; 8- drainage corridor; 9- syncline core; 10- crown beam; 11- prestressed anchor cable; 12- sliding surface; 13- base boundary line; 14- strong weathering boundary line; 15- groundwater level line; 16- bottom boundary of landslide body; 17- ground line; 18- C20 plain concrete backfill; 19- I-beam; 20- lining; 21- anchor rod; 22- bottom plate; 23- side ditch; 24- syncline trough. DETAILED DESCRIPTION
[0031] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.
[0032] It should be noted that in the present invention: the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or apparatuses; the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like are based on the directions or positional relationships shown in the drawings. These The terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation; the terms "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence; the terms "install", "set", "provided with", "connected", "connected", "sleeved", etc. should be understood in a broad sense; for example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be an internal connection between two devices, elements or components. In addition, some terms can be used to express other meanings in addition to indicating orientation or positional relationships. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.
[0033] Embodiment. A method for treating wedge-shaped landslides. The method for treating wedge-shaped landslides is mainly used in landslide treatment, especially for treating wedge-shaped landslides. Since there are syncline structures in the geological characteristics of wedge-shaped landslides, the structures serve as a natural water storage structure. Under the influence of rainfall, rainwater can directly penetrate into the landslide body and gather in the syncline trough on the sliding surface. With the continuous accumulation of rainwater, the water in the syncline trough of the sliding surface gradually forms a pressure state, exerting a supporting force on the upper part of the landslide body. Under the combined action of the sliding force in the landslide body and the supporting force of the pressurized water, sliding deformation occurs. Therefore, the landslide mechanism of the wedge-shaped landslide is different from that of the conventional plane sliding failure. It is obviously unreasonable to continue to use the landslide support form of the plane sliding failure mode to control the wedge-shaped landslide. The landslide support form of the plane sliding failure mode mostly adopts strong support measures such as large-diameter anti-sliding piles or anchor piles for control design, without combing and draining groundwater, thereby reserving engineering hidden dangers. At the same time, it is often adopted to improve the support capacity of the landslide support form by increasing the design size of the anti-sliding piles or anchor piles, the concrete grade, etc., and increase the project investment.
[0034] Therefore, the present invention proposes the following treatment method in view of the characteristics of wedge-shaped landslides, and has been successfully applied in the "Baihushan Hidden Danger Point Treatment Project at the Resettlement Site of Zhexiang Town in the Wangmo Reservoir Area of Longtan Hydropower Station". Figures 1 to 3 As shown, the following steps are included:
[0035] Step 1: According to the size and shape of the landslide body, a drainage ditch 1 is set around the landslide body; the water-passing net section of the drainage ditch 1 is set in a trapezoidal shape, with an upper width of 0.8m, a bottom width of 0.5m, and a depth of 0.5m. It is cast with C25 concrete and a 3cm thick M10 mortar is applied on the surface; by setting up the drainage ditch 1, the water outside the landslide body is collected and discharged to prevent it from entering the landslide body.
[0036] Step 2: A foot retaining wall 7 is set at the front edge of the landslide body along the boundary line of the landslide body, and a drainage ditch 3 is set at the front edge of the foot retaining wall 7; the foot retaining wall 7 adopts a C25 gravity retaining wall, and the wall body is arranged with drainage holes to facilitate the discharge of water in the landslide body; the drainage ditch 3 is set at the front edge of the foot retaining wall 7 to facilitate the collection of water in the landslide body to the drainage ditch 3 for drainage, and the drainage ditch 3 is connected with the intercepting ditch 1 to form a unified drainage system, so as to avoid adding a drainage system to increase the project cost.
[0037] Step 3: Arrange a drainage gallery 8 along the length direction of the syncline core 9 of the landslide body and in the slide bed; the drainage gallery 8 is arranged within a range of 5 to 8 meters below the sliding surface, and the center line of the drainage gallery 8 is in the same plane as the center line of the syncline core 9. The inlet end of the drainage gallery 8 is selected according to the actual project situation. The end of the drainage gallery 8 is set flush with the rear edge of the landslide body. The longitudinal section of the drainage gallery 8 is set with a longitudinal slope of 5‰. The cross-section of the drainage gallery 8 is in the shape of an arch. The arch part of the drainage gallery 8 is evenly arranged with drainage holes 4 along the length direction of the drainage gallery 8. The drainage holes 4 are far away from the drainage gallery 8. The end is arranged in the syncline groove 24, and a drainage blind pipe is arranged in the drainage hole 4; the excavated section of the drainage gallery 8 is supported by I-beams 19 arranged at intervals of 1.5 meters, and 3-meter-long anchor rods 21 are arranged around the I-beams 19 at intervals. A lining 20 is arranged on the inner side of the I-beams 19. The lining 20 is a reinforced concrete structure with a concrete grade of C20 to C25, and the thickness of the lining 20 is 15 to 20 cm; the bottom plate 22 of the drainage gallery 8 is paved with plain concrete and the thickness is consistent with the lining 20; in order to reduce the impact of blasting operations on the landslide body, the drainage gallery 8 is constructed using a cantilever tunneling machine;
[0038] The drainage hole 4 is arranged perpendicular to the arc of the arch portion to increase the radiation range of the drainage hole 4; the length of the drainage hole 4 is determined comprehensively based on the distance between the sliding surface and the top of the drainage gallery 8, the radiation range to be drained, and the maximum height to which the groundwater is expected to rise;
[0039] By setting the drainage holes 4, the water in the syncline trough is concentrated and drained into the drainage gallery 8 for discharge, so as to lower the groundwater level in the syncline trough to the vicinity of the sliding surface, reduce the supporting force of the groundwater in the syncline trough on the landslide body, and increase the stability of the landslide body;
[0040] A side ditch 23 is provided on the bottom plate 22 of the drainage gallery 8 along the length direction of the drainage gallery 8 ; the side ditch 23 is provided to facilitate the collection and outflow of water flowing into the drainage gallery 8 .
[0041] Step 4: Set a row of embedded anti-slide piles 5 perpendicular to the length direction of the syncline core 9 at the position of half of the maximum residual downward sliding force of the landslide body; the length of the bottom end of the embedded anti-slide pile 5 buried in the sliding surface accounts for one-third of the total pile length, and the range from the upper end of the embedded anti-slide pile 5 to the ground is backfilled with C20 plain concrete, and the plain concrete accounts for one-third to one-half of the total buried depth; the embedded anti-slide piles 5 used in this project have a pile diameter of 2.0 meters, a pile spacing of 4.0 meters, and are cast with C30 concrete. In order to avoid squeezing and damage of adjacent piles during construction, skipping pile construction is adopted.
[0042] Step 5: A row of anchor piles 6 is set perpendicular to the length direction of the syncline core 9 at the position of one-third of the maximum residual sliding force of the landslide body; the pile heads of the anchor piles 6 are set out of the ground, and the pile heads of the anchor piles 6 are connected to each other through a crown beam 10. A prestressed anchor cable 11 is set on the crown beam 10, and the end of the prestressed anchor cable 11 away from the crown beam 10 is anchored below the bottom boundary 16 of the landslide body; in this project, the size of the crown beam 10 is 2.0×1.5 meters (width×height), and a crown beam 10 is set for every 3 to 5 anchor piles 6, and the crown beam 10 is cast with C30 concrete; the prestressed anchor cable 11 is set to play a dual role of controlling the horizontal displacement of the anti-sliding pile and reinforcing the landslide body. In this project, the prestressed anchor cable 11 is composed of 1×7 standard 9S15.2 prestressed steel strands with a hole diameter of Φ=200mm. The length of the anchor cable is dynamically adjusted according to the actual geological conditions exposed on site. The anchor cable anchoring section enters the complete bedrock for no less than 8.0m, and the free section is fully grouted. By arranging the embedded anti-slide piles 5 at the half position of the maximum residual sliding force of the landslide body and the anchor piles 6 at the one-third position of the maximum residual sliding force to divide the landslide body into three parts, the landslide body can be effectively divided and decomposed into several relatively stable sections; at the same time, the half position of the maximum residual sliding force of the landslide body and the one-third position of the maximum residual sliding force are selected. Compared with arranging the embedded anti-slide piles 5 or the anchor piles 6 at the position where the maximum residual sliding force is the largest, the forces on the embedded anti-slide piles 5 or the anchor piles 6 are relatively not unconcentrated, the bending moment and shear force they bear are relatively small, and the embedded anti-slide piles 5 or the anchor piles 6 are not easily damaged, which can reduce the damage to the embedded anti-slide piles The requirements for the strength and rigidity of the sliding pile 5 or the anchor pile 6 make the design of the embedded anti-sliding pile 5 or the anchor pile 6 more economical and reasonable, reducing the engineering cost and construction difficulty, while meeting the engineering safety. At the same time, after the anti-sliding piles are set at the half position of the maximum residual sliding force of the landslide body and the one-third position of the maximum residual sliding force, the pile body transmits the sliding force of the landslide body to the surrounding rock and soil, so that the sliding force is effectively diffused and transmitted in the rock and soil, thereby reducing the stress concentration phenomenon inside the landslide body, improving the stress state of the landslide body, and being beneficial to improving the overall stability of the landslide body, preventing the formation of new sliding surfaces or aggravating the development of the original sliding surfaces due to excessive stress in the local area.
[0043] Obviously, the above is only a part of the embodiments of the present invention, not all of the embodiments. The above embodiments are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and variations. Any combination, modification, equivalent replacement, improvement and all other embodiments that can be made by those of ordinary skill in the art within the spirit and principle of the present invention should be within the protection scope of the present invention.
Claims
1. A method for treating a wedge-shaped landslide, characterized in that: The following steps are involved: Step 1: According to the size and shape of the landslide body, a drainage ditch is set around the landslide body (1); Step 2: a foot retaining wall (7) is provided at the front edge of the landslide body along the boundary line of the landslide body, and a drainage ditch (3) is provided at the front edge of the foot retaining wall (7); Step 3: excavating a drainage gallery (8) along the length direction of the oblique core (9) of the landslide body and within the slide bed; Step 4: a row of embedded anti-slide piles (5) are arranged perpendicular to the length direction of the syncline core (9) at a position where the maximum residual sliding force of the landslide body is half; Step 5: a row of anchor piles (6) is arranged perpendicular to the length direction of the syncline core (9) at a position of one third of the maximum residual sliding force of the landslide body.
2. The method for treating wedge-shaped landslide according to claim 1, characterized in that: The drainage ditch (3) is connected to the intercepting ditch (1).
3. The method for treating wedge-shaped landslide according to claim 1, characterized in that: The drainage gallery (8) is arranged within a range of 5 to 8 meters below the sliding surface, and the center line of the drainage gallery (8) is in the same plane as the center line of the syncline core (9). The inlet end of the drainage gallery (8) is selected according to the actual engineering situation. The end of the drainage gallery (8) is arranged flush with the rear edge of the landslide body. The longitudinal section of the drainage gallery (8) is arranged with a longitudinal slope of 5‰. The cross-section of the drainage gallery (8) is in the shape of an arch. The arch part of the drainage gallery (8) is evenly arranged with drainage holes (4) along the length direction of the drainage gallery (8). The end of the drainage hole (4) away from the drainage gallery (8) is arranged in the syncline groove (24). A drainage blind pipe is arranged in the drainage hole (4); the direction of the drainage hole (4) is arranged perpendicular to the arc of the arch part.
4. The method for treating wedge-shaped landslide according to claim 3, characterized in that: A side ditch (23) is provided on the bottom plate (22) of the drainage gallery (8) along the length direction of the drainage gallery (8).
5. The method for treating wedge-shaped landslide according to claim 1, characterized in that: The length of the bottom end of the embedded anti-slip pile (5) embedded in the sliding surface accounts for one third of the total pile length.
6. The method for treating wedge-shaped landslide according to claim 1, characterized in that: The pile heads of the anchor piles (6) are arranged to extend out of the ground, and the pile heads of the anchor piles (6) are connected to each other through a crown beam (10). A prestressed anchor cable (11) is arranged on the crown beam (10), and one end of the prestressed anchor cable (11) away from the crown beam (10) is anchored below the bottom boundary (16) of the landslide body.