CN-122013622-A - Semi-rigid combined supporting structure of high-steep road embankment and design method thereof

CN122013622ACN 122013622 ACN122013622 ACN 122013622ACN-122013622-A

Abstract

The invention discloses a semi-rigid combined supporting structure of a high-steep road embankment and a design method thereof, wherein the supporting structure of the road embankment comprises a counter weight type retaining wall, the counter weight type retaining wall is arranged on a medium-wind slate of a slope toe, a reinforcement area is arranged above the counter weight type retaining wall, and reinforcement materials are paved in layers in the reinforcement area; A reinforced modified soil cushion layer is horizontally paved between the reinforced area and the top of the balance weight type retaining wall, and reinforced materials are paved in the reinforced modified soil cushion layer in a full-section mode, and the reinforced materials in the reinforced modified soil cushion layer are not anchored with the balance weight type retaining wall. And optimizing the length of the reinforcement and the height of the retaining wall according to different damage modes until the anti-slip stability coefficient and the anti-overturning stability coefficient meet the standard requirements. The invention utilizes the counter weight platform of the counter weight type retaining wall to enable the gravity center of the wall body to move backwards, enhances the synergistic effect of the counter weight type retaining wall and the reinforcement, improves the stability of the supporting structure of the high-steep road embankment, reduces the construction cost and realizes the dual aims of saving the cost and optimizing the engineering performance.

Inventors

YU WEN
QIU XIANG
ZHANG SHUJUN
ZENG LING
He ningbo
YIN QIAN
ZHOU YANING
WANG YIFAN

Assignees

中国安能集团第三工程局有限公司
长沙理工大学

Dates

Publication Date: 20260512
Application Date: 20251230

Claims (10)

1. The semi-rigid combined type supporting structure of the high-steep road embankment comprises a road embankment supporting structure and a drainage system, and is characterized in that the road embankment supporting structure comprises a counter weight type retaining wall (5), a counter weight table is arranged on the back of the counter weight type retaining wall (5), the counter weight type retaining wall (5) is arranged on a medium-impact slate (2) of a slope toe, a reinforcement area (3) is arranged above the counter weight type retaining wall (5), and reinforcement materials are paved in the reinforcement area (3) in a layering manner; The reinforced modified soil cushion layer (4) is horizontally paved between the reinforced area (3) and the top of the balance weight type retaining wall (5), the reinforced materials are paved in the reinforced modified soil cushion layer (4) in a full-section mode, and the reinforced materials in the reinforced modified soil cushion layer (4) are not anchored with the balance weight type retaining wall (5).
2. A semi-rigid combined support structure for a high and steep embankment according to claim 1, characterized in that the reinforced area (3) comprises a modified part and a non-modified part, the modified part extends from the side slope surface of the embankment to the interior of the embankment to form a platform, and the rest is the non-modified part.
3. The semi-rigid combined supporting structure of the high-steep road embankment according to claim 1, wherein the outer side of the medium-impact slate (2) at the slow slope section and the steep slope section above the reinforced area (3) is a soil filling area (1), the area among the balance weight type retaining wall (5), the medium-impact slate (2) and the reinforced modified soil cushion layer (4) is the soil filling area (1), and the joint of the soil filling area (1) behind the balance weight type retaining wall (5) and the medium-impact slate (2) is provided with a step structure.
4. The semi-rigid combined supporting structure of the high-steep road embankment according to claim 2 is characterized in that non-modified parts of the reinforced area (3) are filled with plain soil in a layered mode, modified parts of the reinforced area (3) are filled with modified soil in a layered mode, and the modified soil is formed by mixing cement and plain soil according to a mass ratio of 2:25-1:10.
5. The semi-rigid combined supporting structure of the high-steep road embankment according to claim 1, wherein the drainage system comprises a longitudinal drainage ditch of the embankment slope, a continuous drainage layer and drainage holes in front of the wall, the longitudinal drainage ditch is positioned on the surface of the embankment slope, and one longitudinal drainage ditch is arranged at fixed intervals along the longitudinal direction of the embankment slope and extends from the slope top to the slope bottom; The continuous drainage layer is positioned in a soil filling area (1) on the back of the counter-balanced retaining wall (5) and is filled by water seepage materials; The drainage hole before the wall is a row of PVC pipe of diameter 50~100mm, sets up in the position that is higher than embankment basement fixed distance, and outer end downward sloping, the continuous drainage layer of inner embedding, the pipe shaft parcel is strained geotechnique in the opposite directions.
6. A method of designing a semi-rigid combined support structure for a high-steep road embankment according to claim 1, comprising the steps of: S1, identifying a damage mode of overall instability; s2, aiming at the mode one, a sliding surface shears a reinforcement area (3) and reinforcement materials are pulled out of a slope, searching the most dangerous sliding surface (6) of the embankment through software, dividing soil above the most dangerous sliding surface (6) and positioned at the inner side of the reinforcement area (3) into a plurality of vertical soil strips, and calculating unbalanced thrust transmitted by the soil strips close to the reinforcement area by adopting an unbalanced thrust method, so that the length of the reinforcement materials in the reinforcement area (3) required by resisting the unbalanced thrust is determined; S3, aiming at the second mode, the soil body slides out from the top of the balance weight type retaining wall (5), and the residual sliding force under the working condition of combining the thicknesses of different reinforced modified soil cushion layers (4) and the heights of the balance weight type retaining wall (5) is calculated, so that the optimal combination of the thicknesses of the reinforced modified soil cushion layers (4) and the heights of the balance weight type retaining wall (5) is determined; S4, aiming at a mode III, overturning or sliding of the counter weight type retaining wall (5), determining inclination angles of an imaginary wall back, an upper wall back and a lower wall back according to the height of the counter weight type retaining wall (5) determined by the mode II, and calculating three potential fracture surface inclination angles corresponding to the imaginary wall back, the upper wall back and the lower wall back, namely inclination angles of a second fracture surface, a first fracture surface and a lower wall fracture surface; Establishing a moment balance equation for soil between the second fracture surface and the first fracture surface, determining the number of the bars penetrated by the most dangerous sliding surface (6) based on the results of the mode one and the mode two, and further solving the resistance of the bars on the left side of the first fracture surface Establishing a static equilibrium equation in the horizontal direction and the vertical direction, and solving the soil pressure of the second fracture surface And a first fracture surface soil pressure ; For the soil body between the second fracture surface and the back of the retaining wall, the soil pressure based on the second fracture surface Solving the soil pressure of the upper wall back through a static equilibrium equation in the horizontal direction and the vertical direction And counter-weight soil pressure ; For the soil body between the first fracture surface and the lower wall fracture surface, establishing a moment balance equation, and solving the resistance of the left side rib material of the lower wall fracture surface Establishing a static equilibrium equation in the horizontal direction and the vertical direction based on the first fracture surface soil pressure Resistance of left side rib material of first fracture surface And resistance of left side rib material of lower wall fracture surface Solving the soil pressure of the lower wall back ; S5, calculating an anti-sliding stability coefficient and an anti-overturning stability coefficient according to the calculation result of the S4, and if the anti-sliding stability coefficient and the anti-overturning stability coefficient do not meet the standard requirements, adjusting the size or the arrangement of the ribs of the balance weight type retaining wall (5) until the anti-sliding stability coefficient and the anti-overturning stability coefficient meet the standard requirements.
7. The method for designing a semi-rigid combined supporting structure for a high-steep road embankment according to claim 6, wherein in the step S4, a first fracture surface soil pressure is selected And the soil pressure of the second fracture surface The intersection point of the resultant force acting lines of the first fracture surface is taken as a moment center, and the resistance of the left side rib material of the first fracture surface Calculated according to the following formula: ; Wherein, the 、 And Respectively are 、 And Is the perpendicular distance of the line of action to the centre of moment, Is the soil gravity between the second fracture surface and the first fracture surface, Is the resistance of the rib material on the right side of the second fracture surface, Allowable tension of the bar material in the calculation of (a) The method comprises the steps of obtaining the thickness of a reinforced modified soil cushion layer (4) through a mode II, determining the number of the reinforcements passing through the reinforced modified soil cushion layer (4) by combining the arrangement interval of the reinforcements, obtaining the length of the reinforcements in a reinforced area (3) through a mode I, and determining the number of the reinforcements passing through the most dangerous sliding surface (6) in the reinforced area (3) above the reinforced modified soil cushion layer (4) by combining the position of the most dangerous sliding surface (6); soil pressure of the second fracture surface Calculated according to the following formula: ; first fracture surface soil pressure Calculated according to the following formula: ; Wherein, the Representing the internal friction angle of an imaginary wall back; is the inclination angle of the first fracture surface; is the inclination of the second fracture surface.
8. The method for designing a semi-rigid combined supporting structure for a high-steep road embankment according to claim 7, wherein in the step S4, the earth pressure of the back of the upper wall is Calculated according to the following formula: ; Soil pressure of balance weight platform Calculated according to the following formula: ; Wherein, the Is the inclination angle of the back of the upper wall; representing the weight of the soil mass between the second fracture surface and the back of the retaining wall.
9. The method for designing a semi-rigid combined supporting structure for a high and steep road embankment according to claim 8, wherein in the step S4, the resistance of the left side rib of the broken surface of the lower wall is Calculated according to the following formula: ; Wherein, the Representing the resistance of the left-hand rib of the first fracture surface A perpendicular distance from the line of action to the centre of moment; Representing the first fracture surface soil pressure A perpendicular distance from the line of action to the centre of moment; Representing the gravity of soil mass between the first fracture surface and the lower wall fracture surface A perpendicular distance from the line of action to the centre of moment; Representing the resistance of the left side rib material of the fracture surface of the lower wall A perpendicular distance from the line of action to the centre of moment; Soil pressure of lower wall back Calculated according to the following formula: ; Wherein, the The inclination angle of the fracture surface of the lower wall is the inclination angle; Representing the internal friction angle of the lower wall back; Is the inclination angle of the back of the lower wall.
10. The method for designing a semi-rigid combined support structure for a high-steep road embankment according to claim 6, wherein in the step S5, the anti-slip stability factor is as follows Calculated according to the following formula: ; coefficient of stability against capsizing Calculated according to the following formula: ; Wherein, the In order to provide a coefficient of friction, Represents the gravity of the counter-balanced retaining wall (5), Representing the earth pressure of the back of the wall A horizontal component of force; Representing the earth pressure of the back of the wall Is a vertical component of force; representing the earth pressure of the back of the lower wall A horizontal component of force; representing the earth pressure of the back of the lower wall Is a vertical component of force; 、 And Respectively is 、 And The vertical distance from the action line of the counter-balanced retaining wall toe; And Respectively is And The vertical distance from the action line of the counter-balanced retaining wall toe; Representation of Is a vertical distance from the line of action of the counter-balanced retaining wall toe.

Description

Semi-rigid combined supporting structure of high-steep road embankment and design method thereof Technical Field The invention belongs to the technical field of computer-aided roadbed design, and relates to a semi-rigid combined supporting structure of a high-steep road embankment and a design method thereof. Background The highway network is continuously extended towards the mountain heavy-hilly area, and a large number of high-steep embankment sections are formed. The prior reinforcement technology faces double challenges of stability and economy when treating the high-steep road embankment slope engineering. The construction method is mainly characterized in that ① traditional embankment filling and supporting technology is used for reinforcing the whole embankment, stress characteristics of the embankment are not reasonably utilized, so that serious unreasonable phenomena exist in the paving length of the reinforced area, resource waste is caused, engineering cost is increased, under the working condition of ② high-steep embankment, the traditional balance weight type retaining wall excessively depends on dead weight to resist soil pressure, the material consumption is obviously increased due to the increase of the height of the wall body, economical efficiency is reduced, and the ③ high-steep embankment is large in filling height and steep in gradient, and often faces engineering problems of large soil pressure, high sliding and overturning risks and the like. Therefore, a novel high-steep road embankment supporting structure with both safety and economy needs to be developed. The invention patent with publication number of CN110258220A discloses a method for ecologically filling road embankment by using high-strength steel wire mesh reinforced materials, which integrally reinforces the filled embankment by using the high-strength steel wire mesh, although the whole shear strength of the embankment side slope can be improved, the embankment below the road only receives the pressure of upper load, the material waste can be caused when the embankment is reinforced, and the engineering cost is increased. The invention patent with publication number CN118774169A discloses a high-filling embankment of a complex steep terrain balance weight type retaining wall and a construction method, and the invention adopts a pile foundation and bearing platform integrated structure, solves the stability problem of a complex steep section balance weight type retaining wall foundation, improves the bearing capacity of the foundation, but only considers the bearing capacity requirement of the balance weight type retaining wall below 5m-6m on the steep slope embankment support, and does not fully consider the stability requirement. In summary, the existing high-steep road embankment reinforcement method has the following problems: (1) The existing high-steep road embankment reinforcement method generally adopts an integral reinforcement strategy, is not designed differently according to the stress characteristics of different areas of the embankment, so that the material waste and the cost are increased, the laying length of the reinforcement materials is not optimized by combining with the local stability calculation result, and redundancy or deficiency is caused. (2) Under the working condition of the high and steep road embankment, the gravity type retaining wall excessively depends on dead weight to resist soil pressure, and the continuous increase of the height of the wall body leads to obvious increase of material consumption and reduction of economical efficiency. (3) The existing reinforcing method usually designs the retaining wall and the reinforced material as independent components, and lacks deep consideration of a cooperative working mechanism of the retaining wall and the reinforced material, so that an organic whole cannot be formed between the post-wall filling soil and the reinforced soil and the retaining wall, and the overall stability potential of the structure is not fully mobilized. Disclosure of Invention In order to solve the problems, the invention provides a semi-rigid combined supporting structure of a high-steep road embankment, which is formed by combining a reinforced area, a reinforced modified soil cushion layer and a balance weight type retaining wall, wherein the balance weight platform of the balance weight type retaining wall is utilized to enable the gravity center of a wall body to move backwards, so that the synergistic effect of the balance weight type retaining wall and a reinforcement material is enhanced, the stability of the supporting structure of the high-steep road embankment is improved, the engineering cost is reduced, and the dual aims of cost saving and engineering performance optimization are realized. The invention further aims to provide a design method of the semi-rigid combined supporting structure of the high-steep road embankment. The technical scheme includes that