A reinforcement structure and method for earthquake-damaged highway slopes with steep ice-water deposits

Abstract

This application provides a reinforcement structure and method for steep, high-altitude glacial meltwater slopes damaged by earthquakes, relating to the field of highway slope engineering reinforcement technology. The structure includes: a toe protection reinforcement structure, installed at the toe of a glacial meltwater slope formed when a highway traverses steep terrain; a slope retaining wall structure, installed on the main surface of the glacial meltwater slope; a retaining wall combination structure, a collaborative support system designed to adapt to changes in road curvature and differences in fill and cut sections; and a composite anchoring structure, which enhances the strength of the soil and rock mass through grouting and mechanical anchoring. This structure can improve the reinforcement effect on steep, high-altitude glacial meltwater slopes damaged by earthquakes, and reduce the safety hazards of slope instability.

Description

Technical Field

[0001] This application relates to the field of highway slope engineering reinforcement technology, specifically to a reinforcement structure and method for earthquake-damaged highway slopes with steep ice-water deposits. Background Technology

[0002] Glacial meltwater deposits are a special type of rock and soil mass formed by the accumulation of debris carried by glacial meltwater. They are characterized by loose structure, uneven particle size distribution, and high porosity, and are widely distributed in high-altitude mountainous areas of Southwest China. Under steep terrain conditions, when highways traverse this type of slope, external geological forces such as slope cutting, long-term vehicle loads, and long-term rainfall infiltration significantly reduce the stability of glacial meltwater slopes. Especially under sudden earthquakes, the surface soil of the slope will loosen and crack, leading to a significant reduction in the shear strength of the rock and soil mass, inducing shallow, multi-stage landslides, and seriously threatening the lives and property of surrounding residents and the safety of highway construction and operation.

[0003] Existing reinforcement technologies are mostly designed for ordinary rock or soil slopes, making it difficult to meet the special reinforcement needs of steep, glacial meltwater-damaged slopes after earthquakes. This is mainly reflected in the following four aspects: First, the compatibility between steep, loose debris slopes and the repeatedly undulating alignment of highways; second, the lack of coordinated control measures for multiple potential slip surfaces, resulting in the coexistence of shallow collapse and deep sliding problems; third, the slow setting and low early strength of traditional grouting materials, which cannot meet the rapid stabilization requirements of loose strata after an earthquake; and fourth, insufficient scour prevention and design at the slope toe, which easily triggers secondary disasters. Therefore, existing technologies have relatively low reinforcement effects on steep, glacial meltwater-damaged highway slopes after earthquakes, and are prone to safety hazards. Summary of the Invention

[0004] This application provides a reinforcement structure and method for earthquake-damaged slopes of steep highways with glacial deposits. By constructing a multi-level collaborative defense system from the slope toe to the slope top and from the surface to the deep layer, the reinforcement effect of earthquake-damaged slopes of steep highways with glacial deposits is significantly improved, and the safety hazards of instability of earthquake-damaged slopes of steep highways with glacial deposits are reduced.

[0005] In a first aspect, embodiments of this application provide a reinforcement structure for earthquake-damaged slopes with steep, high-altitude ice-water deposits along highways, comprising:

[0006] A toe protection and reinforcement structure is provided at the toe of a glacial water deposit slope formed when a highway crosses steep terrain. The toe protection and reinforcement structure includes an anti-scour wall and an anti-scour toothed wall. The anti-scour wall is erected on the toe of the glacial water deposit slope on the side subjected to water scour, and the anti-scour toothed wall is embedded in the toe foundation below the anti-scour wall.

[0007] A slope retaining wall structure is provided on the main surface of the glacial meltwater deposit slope. The slope retaining wall structure includes a stepped foundation retaining wall and a first anchor. The stepped foundation retaining wall is arranged in stages along the slope topography of the glacial meltwater deposit slope. The first anchor is installed in the target stepped foundation retaining wall. The target stepped foundation retaining wall is determined by the geological conditions of the glacial meltwater deposit slope or the load of the stepped foundation retaining wall.

[0008] The retaining wall combination structure includes a widened retaining wall and a support retaining wall. The widened retaining wall is set in segments along the curvature of the road's spiral route, and the support retaining wall is combined with the slope blind ditch of the glacial water accumulation body slope.

[0009] The composite anchoring structure includes a steel perforated pipe and a second anchor. The steel perforated pipe is set at a preset spacing and a preset angle on the side of the slope excavation line away from the excavation area. The second anchor is embedded in the ice water accumulation body in the top area of ​​the ice water accumulation body slope.

[0010] In some embodiments, the height of the scour barrier is higher than the design flood level, and the embedment depth of the scour barrier toothed wall is not less than the estimated scour depth of the slope toe foundation.

[0011] In some embodiments, the height of each step of the stepped foundation retaining wall is greater than or equal to one meter and less than or equal to three meters; the width of each step of the stepped foundation retaining wall is greater than or equal to two meters and less than or equal to three meters.

[0012] In some embodiments, the overlap length between the foundation of each retaining wall level and the toe of the upper step slope is greater than or equal to 0.5 meters and less than or equal to 1 meter.

[0013] In some embodiments, the first anchor is connected to the stepped foundation retaining wall in a stepped manner.

[0014] In some embodiments, the foundation of the widened retaining wall is a stepped replacement foundation, the wall body of the widened retaining wall is segmented along the curvature of the road spiral line, and the widened retaining wall is provided with drainage holes, and a filter layer is laid behind the drainage holes.

[0015] In some embodiments, the retaining wall is arranged in an arc shape along the curvature of the road spiral, and the retaining wall is provided with drainage holes that are connected to the slope blind ditch.

[0016] In some embodiments, the steel pipe is provided with grouting holes in its body.

[0017] In some embodiments, one end of the second anchor is provided with a helical blade.

[0018] Secondly, embodiments of this application provide a method for reinforcing earthquake-damaged slopes of steep highways with ice-water deposits, including:

[0019] A geological model of a glacial meltwater deposit slope was constructed based on topographic feature data and hydrological monitoring data of the highway; the glacial meltwater deposit was formed when the highway traversed steep terrain.

[0020] The slope safety factor is calculated based on the geological model; the slope safety factor characterizes the location of the potential sliding surface and the stress-displacement distribution characteristics of the slope, and is used to determine the existing slope stability and instability risk points;

[0021] Construct a three-dimensional model of the first slope, and determine the highway spiral trajectory based on the necessary control points of the highway in the three-dimensional model of the first slope;

[0022] A three-dimensional model of the second slope is constructed, and the second three-dimensional model of the slope is integrated with the geological model. The initial stability of the slope is calculated according to the construction points. Based on the initial stability of the slope, the location of the reinforcement structure for the earthquake-damaged slope of the high and steep highway ice water accumulation body is determined.

[0023] The second slope three-dimensional model is the slope three-dimensional model after excavation and filling, and the highway steep ice-water accumulation earthquake-damaged slope reinforcement structure is the highway steep ice-water accumulation earthquake-damaged slope reinforcement structure described above.

[0024] Compared with existing technologies, the beneficial effects of this application are as follows: In the reinforcement structure of steep highway icy-water accumulation damaged by earthquakes, the toe reinforcement structure, through the composite design of anti-scour walls and anti-scour toothed walls, curbs the instability caused by water erosion at the toe of the slope. The slope retaining wall structure breaks down the slope into parts, realizing the layered transfer of load and deep anchoring, thereby suppressing shallow and deep sliding of the slope. The retaining wall combination structure is adapted to the complex alignment of the highway spiral road. Through the differentiated design of the widened retaining wall and the support retaining wall, the eccentric load in the fill area and the slope support requirements in the cut area are balanced. The composite anchoring structure, through the grouting improvement of steel pipes and the deep anchoring of the second anchor, binds the loose accumulation into a whole, which can improve the slope's own strength and integrity. The reinforcement structure for earthquake-damaged slopes with high and steep glacial deposits along highways can significantly improve the reinforcement effect and reduce the safety risks of slope instability by constructing a multi-level collaborative defense system from the slope toe to the slope top and from the surface to the deep layers. Attached Figure Description

[0025] Figure 1 A schematic diagram of a slope reinforcement structure for steep, ice-water accumulation bodies damaged by earthquakes, provided in an embodiment of this application.

[0026] Figure 2This is a flowchart illustrating the method for reinforcing steep, high-altitude slopes damaged by earthquakes due to ice-water accumulation, as provided in this application embodiment.

[0027] Figure 3 This is a schematic diagram of a highway loop road provided in an embodiment of this application.

[0028] Attached reference numerals: 10-Toe reinforcement structure; 11-Impact wall; 12-Impact toothed wall; 20-Slope retaining wall structure; 21-Step foundation retaining wall; 22-First anchor; 30-Retaining wall combination structure; 31-Wide retaining wall; 32-Support retaining wall; 40-Composite anchoring structure; 41-Steel perforated pipe; 42-Second anchor. Detailed Implementation

[0029] The present application will now be described in further detail with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the subject matter of the present application to the following embodiments. All technologies implemented based on the content of the present application fall within the scope of protection of the present application.

[0030] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," "outer," and "side" used in the description of specific embodiments of this application to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the solution in this application or simplifying the description in specific embodiments, so as to enable those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on this application.

[0031] In the description of the embodiments of this application, technical terms such as "first" and "second" only distinguish one entity or operation from another, and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] During the research process, the applicant found that the existing technology has a low reinforcement effect on steep, icy-water-accumulated slopes damaged by earthquakes, resulting in prominent safety hazards. This is mainly due to multiple mismatches between the existing reinforcement schemes and the special geological conditions and engineering requirements of such slopes. Existing technical solutions are mostly designed for ordinary rock or soil slopes, failing to fully consider the complex characteristics of glacial-water deposits, such as loose structure, uneven particle size distribution, well-developed pore water, and the tendency to form multiple potential sliding surfaces after earthquake damage. Their reinforcement approaches are often simplistic, lacking coordinated design for key aspects such as slope toe erosion resistance, graded slope support, route curvature adaptation, and deep anchoring. For example, some solutions only focus on surface protection while neglecting the control of deep sliding surfaces, or only use traditional retaining walls, which cannot adapt to the eccentric loads and differences in slope ratios between the inner and outer sides caused by the winding road alignment in steep terrain. At the same time, traditional grouting materials have slow setting time and low early strength, making it difficult to meet the urgent requirement of rapid stabilization of loose strata after earthquakes. Ultimately, the existing technical system cannot form a holistic and targeted reinforcement effect, making the slope prone to local instability or even traction failure under vehicle loads, long-term rainfall, or earthquake recurrence, posing serious safety hazards.

[0034] Based on this, this application provides a reinforcement structure for steep highway slopes damaged by glacial meltwater deposits, to improve the reinforcement effect and reduce the safety hazards of such slopes. Please refer to... Figure 1 , Figure 1 A schematic diagram of a highway slope reinforcement structure for steep, icy-water-damaged slopes provided in this application embodiment. The highway slope reinforcement structure for steep, icy-water-damaged slopes may include:

[0035] The toe protection reinforcement structure 10 is installed at the toe of the glacial water deposit slope formed when the highway crosses steep terrain. The toe protection reinforcement structure 10 includes an anti-scour wall 11 and an anti-scour toothed wall 12. The anti-scour wall 11 is erected on the toe of the glacial water deposit slope on the side subjected to water scour, and the anti-scour toothed wall 12 is embedded in the foundation at the toe of the slope below the anti-scour wall 11.

[0036] The slope retaining wall structure 20 is set on the main surface of the glacial deposit slope. The slope retaining wall structure 20 includes a stepped foundation retaining wall 21 and a first anchor 22. The stepped foundation retaining wall 21 is set in stages according to the slope topography of the glacial deposit slope. The first anchor 22 is arranged in the target stepped foundation retaining wall 21. The target stepped foundation retaining wall is determined by the geological conditions of the glacial deposit slope or the load of the stepped foundation retaining wall.

[0037] The retaining wall combination structure 30 includes a widened retaining wall 31 and a support retaining wall 32. The widened retaining wall 31 is set in sections along the curvature of the road spiral line, and the support retaining wall 32 is combined with the slope blind ditch of the ice water accumulation body slope.

[0038] The composite anchoring structure 40 includes a steel pipe 41 and a second anchor 42. The steel pipe 41 is set at a preset spacing and a preset angle on the side of the slope excavation line away from the excavation area. The second anchor 42 is embedded in the ice water accumulation body in the top area of ​​the ice water accumulation body slope.

[0039] In this embodiment, "high and steep terrain" refers to the deep valleys and steep slopes common in high-altitude mountainous areas. Glacial meltwater often accumulates along the foothills or valleys. Due to geological processes such as crustal uplift and river incision, the original depositional platforms are eroded and cut, forming natural slopes with significant height and steep gradients—i.e., natural high and steep slopes. To achieve traffic alignment in such complex terrain, highway engineering requires substantial slope cutting and filling. This excavation disrupts the original stress balance of the slope, creating new and steeper free faces. Simultaneously, the load of the highway itself and the long-term vibration of vehicles during operation can further exacerbate slope instability. Moreover, under sudden earthquake action, the originally loose soil on the slope surface is highly susceptible to seismic cracking and deformation, significantly reducing shear strength and forming "earthquake-damaged slopes," characterized by surface loosening and crack development, which easily induces shallow, multi-level landslides.

[0040] The slope protection and reinforcement structure 10 refers to the protective system installed at the toe of the slope formed by glacial deposits when a highway crosses steep terrain. It is an engineering structure that uses a composite structure to resist water erosion and provide foundation reinforcement. The included scour wall 11 is a water-retaining structure erected vertically on the scour side of the slope toe, its main function being to directly resist the lateral impact of the water flow. The scour toothed wall 12 is a tooth-like structure embedded in the slope toe foundation below the scour wall 11, which enhances the overall anti-slip capability by penetrating into stable strata.

[0041] The slope retaining wall structure 20 refers to a graded retaining system deployed on the main surface of the glacial deposit slope, that is, a retaining wall combination that adopts a stepped, layered arrangement to distribute the load. The stepped foundation retaining wall 21 refers to a stepped retaining wall set at regular intervals along the slope topography, designed according to the principle of "layered bearing capacity." The first anchor 22 refers to the anchor installed in the target stepped foundation retaining wall; specifically, it can be a hollow self-drilling anchor, or other mechanical or bonded anchors with hollow rods, enabling integrated construction of drilling, grouting, and anchoring. The target stepped foundation retaining wall refers to a retaining wall unit that requires special reinforcement, selected based on geological conditions or load distribution, such as a critical retaining wall located in a weak interlayer or bearing significant earth pressure.

[0042] The retaining wall composite structure 30 refers to a composite retaining wall system adapted to the zigzag pattern of the highway, that is, a collaborative support system designed to adapt to changes in route curvature and differences in fill and cut. The widening retaining wall 31 refers to a retaining wall set on the outside of the roadbed to accommodate the widening of the route, and its structure needs to withstand eccentric loads; the support retaining wall 32 refers to a retaining wall set on the cut slope inside the roadbed that works in conjunction with drainage facilities, and is usually combined with slope blind drains to reduce earth pressure.

[0043] The composite anchoring structure 40 refers to a deep reinforcement system that penetrates the slope and retaining wall system, that is, a reinforcement device that enhances the strength of the soil and rock mass through grouting and mechanical anchoring. The steel perforated pipe 41 refers to a steel pipe with grouting holes in its body, which forms a composite reinforcement zone through high-pressure grouting and also serves a drainage function. The second anchor 42 refers to an anchor installed in the slope crest area; it can be a hollow self-drilling anchor rod, or other mechanical or adhesive anchors with hollow rod bodies. Furthermore, one end of the second anchor 42 is equipped with a helical blade, which can cut through the strata and simultaneously inject grout to form the anchoring system.

[0044] Based on this, in the embodiments of this application, "setting" refers to the process of determining the spatial location of the structure according to engineering requirements and installing it, and "embedding" refers to burying the structure into the foundation to the design depth. "Graded setting" refers to a construction method of arranging multiple levels according to certain elevation intervals, such as setting a step every 1m-3m; "combined layout" refers to a configuration method of arranging two or more structures in a coordinated manner, such as the matching setting of the retaining wall 32 and the blind drain.

[0045] In some embodiments, the scour wall 11 of the toe reinforcement structure 10 is an above-water portion, and its height is higher than the design flood level in order to resist the direct impact of water flow and wave action; the scour tooth wall 12 is an extension of the underwater portion, and its embedment depth is not less than the estimated scour depth of the toe foundation in order to maintain the overall stability of the slope structure in the event of potential damage to the foundation by water flow.

[0046] The design flood level can be a theoretically calculated water level determined based on statistical analysis of long-term river hydrological data (such as historical highest water level, rainfall intensity, and watershed characteristics). The estimated scour depth is a predictive geomechanical parameter, which can be an estimate obtained through hydraulic model tests or theoretical calculations based on parameters such as flow conditions and foundation soil properties (such as particle size and cohesion).

[0047] The toe reinforcement structure 10 adopts a "scour-resistant toothed wall + scour-resistant wall toe protection" structure, which can play a dual role in "scour resistance + embedded stability" based on the core design principle. The scour depth is calculated according to the hydrological model, and the dimensions of the toe protection structure are determined by combining the parameters of the foundation soil and rock at the slope toe and the slope ratio. The height of the scour-resistant wall 11 can be set higher than the design flood level, and the thickness can be calculated based on the scour resistance strength. The embedment depth in the foundation is not less than the scour depth. The primary function of this design is to reduce the possibility of flooding. If the flood level exceeds the top of the wall, the water flow will directly scour the backfill soil behind the wall and the upper slope toe, causing rapid soil loss, hollowing out the area behind the retaining wall, and thus leading to the collapse or slippage of the wall. Therefore, the height of the scour barrier is determined based on the design flood level, which can be determined by a comprehensive analysis of the river's historical water level, rainfall intensity, and possible extreme flood events based on a hydrological model. The scour barrier 11 forms an external physical barrier for the slope toe, resisting the force of the water flow outside the scour barrier 11 within the design standards.

[0048] The embedment depth of the scour protection wall 12 is no less than the estimated scour depth of the slope toe foundation, representing a deep defense strategy for foundation stability. Under the erosion of river water or torrential rain runoff, the surface and shallow soil of the slope toe foundation of glacial deposits are continuously eroded, forming scour pits. If the foundation depth of the scour protection wall 11 is insufficient, as the scour pit deepens, the bearing layer beneath the wall foundation will lose effective support, causing the wall to become unstable due to foundation suspension. Embedding the scour protection wall 12 below the estimated scour depth means that even if the foundation soil in front of the wall experiences maximum anticipated scour, the bottom of the wall can still be firmly embedded in the undisturbed stable stratum, utilizing the embedment force of the deep soil to effectively resist potential slippage and overturning tendencies of the wall, thereby ensuring the stability of the entire toe protection system.

[0049] Furthermore, after the design of the toe protection reinforcement structure 10 is completed, the overall safety factor of the slope after the implementation of the toe protection measures can be calculated based on the three-dimensional model. Under flood conditions, the anti-scour wall 11 is simulated to resist the lateral scour force of the water flow, and the anti-scour toothed wall 12 weakens the wall's sliding tendency by embedding the foundation. Secondly, the mechanical calculation of the toe protection structure itself is performed, calculating the overturning stability coefficient and sliding stability coefficient of the anti-scour wall 11, and verifying the shear strength of the toothed section of the anti-scour toothed wall 12. At the same time, through numerical simulation, the collaborative stress characteristics of the toe protection structure and the slope under flood scour are analyzed, verifying the dual effect of the structure on the slope toe of "scour resistance + embedding stability".

[0050] It should be understood that the design scheme of the toe reinforcement structure 10 is also applicable to river valley slope construction sites where the toe of the slope is subject to continuous water flow erosion and the foundation rock and soil have weak erosion resistance. It can effectively curb slope traction instability induced by toe erosion.

[0051] In some embodiments, the design parameter range of the stepped foundation retaining wall 21, including the step height, step width, and foundation overlap length, is an optimized result derived from the core design principle of "layered bearing and embedded stability," and after comprehensively balancing structural safety, construction feasibility, and economy. For slopes composed mainly of boulders and gravelly soil with uneven gradation and localized weak interlayers, stepped foundation retaining walls are used for reinforcement. The division of retaining wall steps and foundation depth are determined by considering the slope top self-weight, vehicle load, and groundwater seepage path. The height of each step of the stepped foundation retaining wall 21 is greater than or equal to one meter and less than or equal to three meters; the width of each step of the stepped foundation retaining wall 21 is greater than or equal to two meters and less than or equal to three meters. The overlap length between each retaining wall foundation and the toe of the upper step is greater than or equal to 0.5 meters and less than or equal to one meter.

[0052] The height of each step is controlled between one and three meters to allow for the gradual digestion of steep, glacial slopes. Excessively high single-step sections would subject the wall to excessive earth pressure, increasing the risk of overturning; conversely, excessively low sections would result in too many tiers, making the structure too fragmented and inefficient. This height range effectively breaks down the steep slope into smaller sections, allowing each retaining wall to independently and stably bear the lateral pressure of the soil behind it, achieving a gradual transfer and distribution of load.

[0053] The width of each step is set at two to three meters. This width design allows the retaining wall foundation to have sufficient distance from the outer edge of the foundation bottom to the edge of the step, which helps to improve the bearing capacity and anti-slip ability of the foundation. In addition, based on construction considerations, this width can provide a reliable working platform for mechanical operation, material stacking and subsequent slope deformation monitoring during construction, making the retaining wall structure itself a carrier for the implementation of auxiliary projects.

[0054] Each retaining wall foundation maintains an overlap length of 0.5 to 1 meter with the toe of the upper step slope. This ensures that the vertical load of the upper retaining wall is effectively transferred through the foundation to the middle and rear foundation of the lower retaining wall, reducing stress concentration at step transitions. This mechanically connects the dispersed retaining walls at each level into a more robust composite structure, collectively resisting the slope's sliding force and reducing the potential for cascading failure due to the independent operation of each retaining wall.

[0055] Furthermore, each retaining wall foundation is equipped with drainage holes, and a gravel filter layer is laid behind the drainage holes. This can help to drain groundwater from the accumulation of sediment on the slope and reduce the additional pressure caused by water accumulation behind the wall.

[0056] Furthermore, the overall stability of the retaining wall and slope can be calculated based on the three-dimensional model. By verifying the strength of the wall section, the anti-slip stability of the foundation and the bearing capacity of the foundation, the stepped foundation can distribute the vertical load of the wall to the deep stable stratum, while the horizontal thrust is offset by the foundation embedment and the first anchor 22.

[0057] Specifically, the first anchor 22 is connected to the stepped foundation retaining wall 21 in a staggered manner. "Staggered arrangement" refers to a pattern of arrangement at specific intervals, such as installing anchors at every other step, every two steps, or at more steps per level. This staggered arrangement effectively controls the overall and local stability of the slope while optimizing material usage and project cost, achieving a balance between safety and economy.

[0058] In sections with relatively good slope stability, the weight of the retaining wall 21 itself and the foundation embedment are sufficient to meet the stability requirements. However, in critical layers with high potential sliding risk or large earth pressure, the larger horizontal thrust borne by the back of the wall can be directly transferred to the deep, stable soil and rock layers by adding a first anchor 22 or reducing the number of intervals between two adjacent first anchors 22, thereby enhancing the retaining wall's resistance to sliding and overturning.

[0059] In some embodiments, the foundation of the widened retaining wall 31 is a stepped replacement foundation. The wall body of the widened retaining wall 31 is segmented along the curvature of the highway spiral route, and drainage holes are provided in the widened retaining wall 31, with a filter layer laid behind the drainage holes. The retaining wall 32 is arranged in an arc shape along the curvature of the highway spiral route, and drainage holes are provided in the retaining wall 32, which are connected to the slope blind ditch.

[0060] Because the ice-water deposits are of mixed materials, building a retaining wall directly on them can easily lead to uneven settlement. Therefore, the foundation of the widened retaining wall 31 can adopt a stepped replacement foundation. By making the foundation into a stepped shape and replacing it with high-quality materials, the bottom area of ​​the foundation can be effectively expanded, and the load transmitted by the wall can be more evenly distributed to the lower strata.

[0061] In this embodiment, the stepped replacement foundation is a composite foundation form used in geotechnical engineering to treat weak or uneven foundations. It combines the "stepped" geometric structure with improved "replacement" materials to expand the foundation base, uniformly transfer loads, and increase the bearing capacity of the foundation. Specifically, "replacement" refers to partially or completely removing the weak soil layer (for glacial deposits, this refers to loosely structured, unevenly bearing colluvial deposits) with low bearing capacity and high compressibility at a certain depth below the foundation base, and then backfilling it in layers with high-strength, stable materials such as crushed stone, lime-soil, or plain concrete, followed by compaction.

[0062] The winding road in the mountainous area contains a large number of curved sections. The wall body of the widened retaining wall 31 is set in segments along the curvature of the winding road, so that each segment is precisely adapted to the curvature change of the route. This is to smoothly connect the retaining wall line and the road line, reduce unnecessary stress concentration in the wall body due to abrupt changes in the line, and improve the structural stability.

[0063] Drainage holes are set in the widened retaining wall 31 and a filter layer is laid behind the holes. The drainage holes provide a drainage channel for groundwater, while the filter layer behind them is used to prevent fine particles in the soil behind the wall from being carried out by the water flow during the drainage process, thereby reducing soil loss and foundation hollowing caused by erosion.

[0064] Similarly, the retaining wall 32 is arranged in an arc shape along the curvature of the route to conform to the curved slope after excavation, forming a continuous and effective support surface. The drainage holes of the retaining wall 32 are directly connected to the blind drains pre-embedded in the slope to form an active three-dimensional drainage system. The blind drains intercept and collect deeper seepage within the slope and discharge it through the drainage holes to reduce the lateral earth pressure acting on the back of the wall.

[0065] In some embodiments, the steel pipe 41 is provided with grouting holes in its body. The second anchor 42 cuts the strata with a spiral blade to form a grouting composite structure in the ice-water accumulation in the slope crest region when liquid grout is injected.

[0066] The grouting holes of the steel pipe 41 are regularly distributed along the longitudinal and circumferential directions of the pipe. During high-pressure grouting, cement grout is injected into the surrounding loose, porous ice-water deposits through these grouting holes. The grout fills the pores inside the soil through the grouting holes and penetrates into the weak sand-clay interlayer. After the grout solidifies, the originally loose debris binds together into a whole, thus forming a significantly stronger "pile-grout composite reinforcement zone" within the slope, composed of the steel pipe and the hardened grout.

[0067] As a preferred embodiment, steel pipes with a length of 9m can be used, and set at a preset spacing of 1.5m × 2.0m and a preset inclination angle of 20° with respect to the horizontal plane, 1m away from the excavation area on the side of the slope excavation line.

[0068] Furthermore, the grouting holes in the steel pipe 41 remain after grouting is completed, allowing the steel pipe 41 to continue its drainage function during use. When groundwater seeps into the slope, the water can enter the hollow cavity of the steel pipe through these grouting holes and be discharged, thereby reducing the hydrostatic pressure behind the wall or on the slope and achieving the dual functions of reinforcement and drainage.

[0069] The second anchor 42 is equipped with a helical blade at its front end for drilling. In glacial deposits rich in boulders, boulders, or loose, easily collapsible boreholes, traditional drilling techniques are prone to problems such as stuck drill bits and borehole collapse. The helical blade of the second anchor 42 can rotate continuously under the drive of the drilling rig, directly cutting and breaking up the soil or obstacles in front, achieving "self-drilling." This eliminates the need for pre-drilling or casing, improving drilling efficiency under adverse geological conditions.

[0070] Furthermore, during the drilling process, cement-water glass dual-liquid grout is injected into the fissures of the surrounding soil through the hollow channel of the second anchor 42. The grout follows the drill bit forward, filling the holes left by the drill bit and the fissures of the surrounding soil, forming a grouting composite structure around the anchor rod that combines the anchor rod body and high-strength grout. This transmits the anchoring force of the anchor rod over a long distance to the deep stable strata, providing pull-out resistance for the bench foundation retaining wall 21 or the slope top area, thereby improving the overall stability of the support system.

[0071] In other embodiments, since the top of the slope is prone to post-collapse due to water damage, a slope-top intercepting ditch can be constructed. This ditch is a drainage channel located at a certain distance behind the slope top to intercept surface runoff (such as rainwater and snowmelt) collected from the slope above the top, reducing direct erosion of the slope surface or infiltration into the slope body. Further reinforcement can be achieved by installing active mesh shotcrete and planting vines in the slope-top area.

[0072] In the aforementioned implementation process, the toe reinforcement structure, through a composite design of scour walls and scour toothed walls, curbs the instability caused by water erosion at the slope toe. The slope retaining wall structure breaks down the slope into smaller parts, achieving layered load transfer and deep anchoring to suppress both shallow and deep landslides. The retaining wall combination structure adapts to the complex alignment of the highway's meandering curves. Differential designs of widened and support retaining walls balance the eccentric loads in the fill area and the slope support requirements in the cut area. The composite anchoring structure 40, through grouting improvement of steel pipes and deep anchoring of the second anchor, binds the loose aggregate into a whole, enhancing the slope's strength and integrity. The highway high-steep glacial water accumulation slope reinforcement structure, by constructing a multi-level collaborative defense system from the slope toe to the top and from the surface to the depth, can significantly improve the reinforcement effect of highway high-steep glacial water accumulation slopes damaged by earthquakes, reducing the safety hazards of slope instability.

[0073] It should be understood that when using the reinforcement structure provided in the above embodiments to reinforce the slope, the division of each structural part in the above description is only used as an example. In practical applications, the above functions can be assigned to different structures as needed. That is, some internal structures can be divided into different parts to complete all or part of the functions described above.

[0074] Based on the same concept, this application also provides a method for reinforcing earthquake-damaged slopes of steep highways with ice-water deposits, which may include:

[0075] A geological model of a glacial-water deposit slope was constructed based on topographic feature data and hydrological monitoring data of the highway; glacial-water deposits are formed when a highway crosses steep terrain.

[0076] The slope safety factor is calculated based on the geological model. The slope safety factor characterizes the location of potential sliding surfaces and the stress-displacement distribution characteristics of the slope, and is used to determine the stability status of existing slopes and the risk points of instability.

[0077] Construct a three-dimensional model of the first slope, and determine the highway spiral trajectory based on the necessary control points of the highway in the three-dimensional model of the first slope;

[0078] A three-dimensional model of the second slope was constructed and integrated with the geological model. The initial stability of the slope was calculated for each work point. Based on the initial stability of the slope, the location of the reinforcement structure for the steep highway ice-water deposit damaged by earthquake was determined.

[0079] Among them, the three-dimensional model of the second slope is the three-dimensional model of the slope after excavation and filling, and the reinforcement structure of the highway steep ice-water deposit damaged by earthquake is the highway steep ice-water deposit damaged by earthquake as described above.

[0080] Please refer to Figure 2 , Figure 2 This is a flowchart illustrating the method for reinforcing steep, high-altitude slopes damaged by earthquakes due to ice-water accumulation, as provided in this application embodiment.

[0081] Before designing a reinforcement structure for a steep, high-altitude slope damaged by seismic ice-water deposits, a site geological model is constructed based on the existing slope topography, deposit characteristics, river system, and seismic intensity. The site's engineering geological conditions are analyzed, and the stability of the existing slope is calculated.

[0082] Specifically, high-precision digital elevation models obtained using UAV aerial surveys and RTK (Real-time kinematic) topographic surveys can clearly depict key topographic features such as slope height and slope angle. Meanwhile, borehole sampling and in-situ testing can determine the material composition, density, and shear strength of the glacial deposits, and investigate potential adverse geological phenomena within them. Based on this data, by comprehensively analyzing the individual and synergistic effects of multiple factors such as topographic conditions, deposit density, river erosion, groundwater seepage, and seismic response, core engineering geological problems such as slope toe erosion and deposit deformation can be accurately identified. Finally, by calculating the slope safety factor, the location of potential sliding surfaces and the distribution characteristics of slope stress and displacement can be identified, thus making a comprehensive judgment on the current stability state and instability risk points of the slope.

[0083] After completing the geological model construction and stability analysis, the next step is to construct a 3D model of the first slope and determine the highway's spiral alignment within this model. The 3D model not only includes detailed topography but also incorporates stratigraphic structure and hydrogeological characteristics obtained from geotechnical tests, becoming an integrated visualization platform. After determining the route's technical specifications based on highway grade and topographical constraints, the highway's spiral alignment is initially drawn using the 3D model as a reference, based on essential control points such as bridge pier locations across rivers.

[0084] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the highway spiral alignment provided in an embodiment of this application. The red line represents the road centerline, indicating the spatial orientation of the route when the highway traverses a high-altitude, steep glacial deposit area. In the design of the highway high-altitude, steep glacial deposit earthquake-damaged slope reinforcement structure, the route alignment is smoothly transitioned by adjusting the radius of the circular curve and the length of the spiral, while also ensuring a balanced longitudinal slope. The direct purpose is to minimize the subsequent excavation and filling work. After the initial alignment is determined, the volumetric calculation function of the 3D model is used to statistically analyze the excavation height and fill thickness of each section. Combined with analysis of soil and rock parameters, the slope ratio after excavation is analyzed. Potentially unstable slopes, such as excavation sections with weak interlayers or fill sections with insufficient foundation bearing capacity, are identified and their risk levels are marked.

[0085] To accurately determine the layout of the reinforcement structure, a second three-dimensional slope model needs to be constructed—that is, a model of the slope after excavation and filling—and deeply integrated with the initial geological model. This integrated model realistically reflects the slope state after engineering disturbance and serves as the direct basis for targeted reinforcement design. On this model, the initial stability of the slope is calculated for different work points. The evaluation results directly determine the optimal placement and form of subsequent reinforcement measures, such as toe protection structures, slope retaining wall structures, retaining wall combination structures, and composite anchoring structures. For example, for work points where the slope toe is susceptible to erosion after excavation and filling, a composite toe protection scheme of erosion control walls and erosion control toothed walls can be determined; for slope work points with chaotic material composition and potential slip surfaces, the layout parameters of stepped foundation retaining walls and self-advancing anchors can be determined.

[0086] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A reinforcement structure for earthquake-damaged slopes with steep, high-altitude ice-water deposits along highways, characterized in that, include: A toe protection and reinforcement structure is installed at the toe of a slope formed by ice water accumulation when a highway crosses steep terrain. The toe protection reinforcement structure includes an anti-scour wall and an anti-scour toothed wall. The anti-scour wall is erected on the slope toe of the ice-water accumulation body on the side subjected to water scour, and the anti-scour toothed wall is embedded in the slope toe foundation below the anti-scour wall. A slope retaining wall structure is provided on the main surface of the glacial meltwater deposit slope. The slope retaining wall structure includes a stepped foundation retaining wall and a first anchor. The stepped foundation retaining wall is arranged in stages along the slope topography of the glacial meltwater deposit slope. The first anchor is installed in the target stepped foundation retaining wall. The target stepped foundation retaining wall is determined by the geological conditions of the glacial meltwater deposit slope or the load of the stepped foundation retaining wall. The retaining wall combination structure includes a widened retaining wall and a support retaining wall. The widened retaining wall is set in segments along the curvature of the road's spiral route, and the support retaining wall is arranged in combination with the slope blind ditch of the ice water accumulation body slope. The widened retaining wall is set on the outside of the roadbed, and the support retaining wall is set on the inside of the roadbed. The composite anchoring structure includes a steel perforated pipe and a second anchor. The steel perforated pipe is set at a preset spacing and a preset angle on the side of the slope excavation line away from the excavation area. The second anchor is embedded in the ice water accumulation body in the top area of ​​the ice water accumulation body slope.

2. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 1, is characterized in that... The height of the scour barrier is higher than the design flood level, and the embedment depth of the scour barrier toothed wall is not less than the estimated scour depth of the slope toe foundation.

3. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 1, is characterized in that... The height of each step of the stepped foundation retaining wall is greater than or equal to one meter and less than or equal to three meters; the width of each step of the stepped foundation retaining wall is greater than or equal to two meters and less than or equal to three meters.

4. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 3, is characterized in that... The overlap length between the foundation of each retaining wall level and the slope toe of the upper step is greater than or equal to 0.5 meters and less than or equal to 1 meter.

5. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 3 or 4, is characterized in that... The first anchor is connected to the stepped foundation retaining wall in a stepped manner.

6. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 1, is characterized in that... The foundation of the widened retaining wall is a stepped replacement foundation. The wall body of the widened retaining wall is set in sections along the curvature of the road spiral line. Drainage holes are provided in the widened retaining wall, and a filter layer is laid behind the drainage holes.

7. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 6, is characterized in that... The retaining wall is arranged in an arc shape along the curvature of the road's spiral path. Drainage holes are provided in the retaining wall and are connected to the slope blind ditch.

8. The slope reinforcement structure for steep highway ice-water deposits damaged by earthquakes, as described in claim 1, is characterized in that... The steel pipe is provided with grouting holes in its body.

9. The slope reinforcement structure for steep highway slopes damaged by ice-water deposits as described in claim 1, characterized in that, One end of the second anchor is equipped with a helical blade.

10. A method for reinforcing earthquake-damaged slopes of steep highways with ice-water deposits, characterized in that, include: A geological model of a glacial-water deposit slope was constructed based on topographic feature data and hydrological monitoring data of the highway. The ice-water deposits were formed when the highway traversed steep terrain. Calculate the slope safety factor based on the geological model; The slope safety factor characterizes the location of potential sliding surfaces and the stress-displacement distribution characteristics of the slope, and is used to determine the existing slope stability and instability risk points. Construct a three-dimensional model of the first slope, and determine the highway spiral trajectory based on the necessary control points of the highway in the three-dimensional model of the first slope; A three-dimensional model of the second slope is constructed, and the second three-dimensional model of the slope is integrated with the geological model. The initial stability of the slope is calculated according to the construction points. Based on the initial stability of the slope, the location of the reinforcement structure for the earthquake-damaged slope of the high and steep highway ice water accumulation body is determined. Wherein, the second slope three-dimensional model is the slope three-dimensional model after excavation and filling, and the highway steep ice-water accumulation earthquake-damaged slope reinforcement structure is the highway steep ice-water accumulation earthquake-damaged slope reinforcement structure according to any one of claims 1-9.

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