Partitioning method for reinforcement control of wide filling body on ground

Abstract

The invention discloses a quick and effective zoning method for reinforcing control of a wide fill body on the ground. A scientific basis and an effective means are provided for reinforcing control zoning design of the wide fill body. According to the zoning method for reinforcement control of the wide-width filling body on the ground, the filling body is divided into a center area, a transition area and a slope area, the transition area and the slope area are located on the two sides of the center area, the center area is defined by a top face center section, vertical faces located on the two sides of the top face center section and a bottom face center section, and the width center line of the top face center section and the width center line of the top face of the wide-width filling body are overlapped; the width of the center section of the top surface is the width of an area in which the ratio of the average shear stress in the vertical direction to the average vertical normal stress in the wide filling body is not greater than 10%; the side slope area is defined by a top surface outer side section, a bottom surface outer side section, an outer slope surface and an inner slope surface, and the outer slope surface is parallel to the inner slope surface; the width of the outer side section of the top surface is the intercept of the potential slip mass on the top surface of the wide filling body; the area except the central area and the side slope area is the transition area.

Description

Technical Field

[0001] The invention relates to the technical field of wide-width fill body reinforcement control, and in particular to a zoning method for wide-width fill body reinforcement control on the ground. Background Art

[0002] Fill is a common type of engineering in railway and highway engineering, usually referred to as embankment engineering. The top width of general embankment engineering is limited. However, in special cases, due to the requirements of the engineering, the top width of the fill is very large and the fill height is high, which is called a wide fill. For wide fill on the ground, its deformation and stability are different in different areas of space, and the fill engineering should be treated differently during reinforcement to form a reasonable engineering fill. However, there is no clear provision for the reinforcement control zoning method for wide fill in the current specifications, which makes the relevant actual engineering lack of theoretical method reference, mostly based on experience, and has blindness in design. Therefore, for wide fill on the ground, a more reasonable reinforcement control zoning method is urgently needed in engineering practice.

[0003] At present, there is a lack of a simple and practical method for the zoning of wide fill reinforcement control on the ground. For some fill roadbed projects, some scholars have divided the fill roadbed into three types: narrow embankment type, transition type and wide embankment type according to the foundation settlement mode and the distance from the maximum foundation settlement point to the center line of the roadbed. However, this fill roadbed classification method does not fully consider the stress distribution characteristics in the fill soil, and only divides the embankment as a whole into three categories without reasonably zoning the specific fill roadbed. In addition, it does not propose what kind of targeted reinforcement control method should be adopted for different areas. Therefore, the current classification method for fill roadbed cannot be used for the reasonable zoning and reinforcement control of wide fill bodies, which makes the relevant engineering design lack a reasonable basis in specific application analysis. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a quick and effective zoning method for reinforcement control of a wide fill body on the ground, so as to provide a scientific basis and effective means for the zoning design of reinforcement control of a wide fill body.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a zoning method for reinforcement control of a wide fill body on the ground, and the technical scheme is as follows:

[0006] The zoning method for the reinforcement control of wide fill bodies on the ground divides the fill body into a central area and a transition area and a slope area on both sides of the central area.

[0007] The central area is surrounded by the top surface central section, the vertical surfaces located on both sides of the top surface central section and the bottom surface central section, wherein the top surface central section overlaps with the width centerline of the top surface of the wide-width fill body; the width of the top surface central section is the width of the area in which the ratio of the average shear stress in the vertical direction to the average vertical normal stress in the wide-width fill body is not greater than 10%;

[0008] The slope area is surrounded by the outer section of the top surface, the outer section of the bottom surface, the outer slope surface and the inner slope surface, wherein the outer slope surface and the inner slope surface are parallel; the width of the outer section of the top surface is the intercept of the potential sliding body on the top surface of the wide fill body;

[0009] The area excluding the central area and the slope area is the transition zone.

[0010] As a further improvement of the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground: the width of the central section of the top surface is calculated using a numerical simulation method.

[0011] As a further improvement of the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground:

[0012] The stress field distribution of the wide fill body is obtained by FLAC3D simulation, and then the width of the area where the ratio of the average vertical shear stress to the average vertical normal stress in the wide fill body is not greater than 10% can be determined, which is the width of the top center section.

[0013] Numerical simulation analysis was performed on wide fill volumes with different fill heights and top surface widths to obtain the corresponding theoretical values ​​of the center section width. Curve fitting was performed on all the obtained theoretical values, and the expression for half of the top surface center section width was obtained as follows:

[0014]

[0015] In the formula, b is half of the width of the center section of the top surface; w is half of the width of the top surface of the wide fill body; m is the inverse of the slope; and H is the fill height of the wide fill body.

[0016] As a further improvement of the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground:

[0017] The calculation result for the horizontal ground is multiplied by the correction coefficient ξ to obtain the correction value of half the width of the center section of the top surface, that is:

[0018] b c =ξb;

[0019] Where b c is the correction value of half the width of the central section of the top surface; ξ is the correction coefficient, which changes with the horizontal inclination angle α of the bottom surface of the wide fill body. When α≤5°, ξ=1; when α=10°, ξ=0.5; when α=15°, ξ=0.3; in other cases, ξ is calculated according to α using the linear difference method.

[0020] As a further improvement to the above-mentioned zoning method for reinforcement control of wide fill bodies on the ground: the central area is compacted and reinforced by the strong tamping method, and the foundation below the central area is reinforced by pile foundation composite foundation or strong tamping method.

[0021] As a further improvement to the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground: the width of the outer section of the top surface is calculated using the plastic limit analysis method or the limit equilibrium method.

[0022] As a further improvement of the above-mentioned zoning method for reinforcement control of wide fill bodies on the ground: the theoretical values ​​of the intercepts of potential sliding bodies of wide fill bodies with different filling heights on the top surface of the wide fill bodies are calculated by using the plastic limit analysis method or the limit equilibrium method. All the obtained theoretical values ​​are curve fitted, and the expression of the width of the outer section of the top surface can be obtained as follows:

[0023]

[0024] Where, L is the width of the outer section of the top surface; m is the inverse of the slope; β is the slope angle of the wide fill body; H is the fill height of the wide fill body; γ is the weight of the fill soil; c is the cohesion of the fill soil; is the internal friction angle of fill soil.

[0025] As a further improvement to the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground: the slope area is reinforced with an anti-slide pile structure, a reinforced soil structure or a retaining wall structure.

[0026] As a further improvement of the above-mentioned zoning method for controlling the reinforcement of wide fill bodies on the ground: the calculation expression for the width of the top transition section of the transition zone is:

[0027] S=wb c -L;

[0028] Where S is the width of the top transition section; w is half the width of the top surface of the wide fill body; L is the width of the outer section of the top surface; b c is the correction value of half the width of the center section of the top surface. If S<0 is calculated, then b is taken c =wL,S=0.

[0029] As a further improvement to the above-mentioned zoning method for reinforcement control of wide fill bodies on the ground: the transition zone is reinforced by combining reinforced earth structure with dynamic compaction method.

[0030] It can be seen that the present invention overcomes the shortcomings of traditional methods and proposes a reinforcement control zoning method for wide fill bodies on the ground based on stress distribution and deformation characteristics. This method fully considers the differences between different areas in the wide fill body and rationally divides the wide fill body into three areas (central area, transition area and slope area), which is convenient for quick operation and makes the reinforcement control zoning easy to understand and calculate.

[0031] Furthermore, the present invention proposes calculation expressions for the range of each area. The algorithm is simple and can simply estimate and determine the reinforcement control partition without time-consuming and labor-intensive experiments, thereby significantly improving the efficiency of engineering design calculations. Moreover, corresponding key reinforcement control methods are further proposed for each area, and the ground level and inclination are taken into consideration, providing fast and effective technical means and algorithmic basis, thereby improving the intuitiveness and efficiency of engineering design.

[0032] In summary, the zoning method for reinforcement control of wide fill bodies on the ground of the present invention is simple to operate, the results are highly referenceable and applicable, and the design calculation and analysis of reinforcement control zoning can be quickly realized, which provides a simple and effective method and scientific basis for the reinforcement control of wide fill bodies, and has important technical significance and engineering application value.

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages of the present invention will be partially given in the following description, partially become apparent from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings constituting a part of the present invention are used to assist in understanding the present invention. The contents provided in the drawings and their related descriptions in the present invention can be used to explain the present invention, but do not constitute improper limitations on the present invention. In the drawings:

[0035] Figure 1 It is a schematic diagram of the zoning of the zoning method for the reinforcement control of a wide fill body on the ground of the present invention when the bottom horizontal inclination angle α≤5°.

[0036] Figure 2 It is a schematic diagram of the zoning of the zoning method for the reinforcement control of a wide fill body on the ground of the present invention when the bottom horizontal inclination angle α is greater than 5°.

[0037] Figure 3 This is a zoning diagram of Example 1 of the zoning method for reinforcement control of a wide fill body on the ground according to the present invention.

[0038] Figure 4 This is a zoning diagram of Example 2 of the zoning method for reinforcement control of a wide fill body on the ground according to the present invention.

[0039] The relevant marks in the above drawings are:

[0040] 100-central area, 110-vertical surface, 200-transition area, 300-slope area, 310-outer slope surface, 320-inner slope surface. DETAILED DESCRIPTION

[0041] The present invention is described clearly and completely below in conjunction with the accompanying drawings. A person skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention in conjunction with the accompanying drawings, it should be particularly noted that:

[0042] The technical solutions and technical features provided in each part of the present invention, including the following description, may be combined with each other if there is no conflict.

[0043] In addition, the embodiments of the present invention involved in the following description are generally only a part of the embodiments of the present invention, rather than all the embodiments. Therefore, based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] About the terms and units in the present invention: The terms "include", "have" and any variations thereof in the description and claims of the present invention and related parts are intended to cover non-exclusive inclusions.

[0045] Figure 1 It is a schematic diagram of the zoning of the zoning method for the reinforcement control of a wide fill body on the ground of the present invention when the bottom horizontal inclination angle α≤5°. Figure 2 It is a schematic diagram of the zoning of the zoning method for the reinforcement control of a wide fill body on the ground of the present invention when the bottom horizontal inclination angle α is greater than 5°.

[0046] like Figure 1-2 As shown, the zoning method for the reinforcement control of a wide fill body on the ground of the present invention divides the fill body into a central area 100 and a transition area 200 and a slope area 300 located on both sides of the central area 100. The central area 100 is surrounded by a top surface central section, vertical surfaces 110 located on both sides of the top surface central section and a bottom surface central section, wherein the top surface central section overlaps with the width centerline of the top surface of the wide fill body; the width of the top surface central section is the width of the area where the ratio of the average shear stress in the vertical direction to the average vertical normal stress in the wide fill body is not greater than 10%. The slope area 300 is surrounded by a top surface outer section, a bottom surface outer section, an outer slope surface 310 and an inner slope surface 320, wherein the outer slope surface 310 and the inner slope surface 320 are parallel; the width of the top surface outer section is the intercept of the potential sliding body on the top surface of the wide fill body. The area excluding the central area 100 and the slope area 300 is the transition area 200.

[0047] The following describes each area in detail.

[0048] 1. Central Area

[0049] The central area is defined as an area with almost no shear stress, with the ratio of the average vertical shear stress in the wide fill body to the average vertical normal stress being no more than 10%, and the center section of the top surface overlaps with the width center line of the top surface of the wide fill body.

[0050] The width of the central section of the top surface of the central area is calculated by numerical simulation. For example, the stress field distribution of the wide fill body is simulated by FLAC3D, and then the width of the area where the ratio of the average vertical shear stress to the average vertical normal stress in the wide fill body is not greater than 10% can be determined, which is the width of the central section of the top surface.

[0051] Numerical simulation analysis was performed on wide fill volumes with different fill heights and top surface widths to obtain the corresponding theoretical values ​​of the center section width. Curve fitting was performed on all the obtained theoretical values, and the expression for half of the top surface center section width was obtained as follows:

[0052]

[0053] In the formula, b is half of the width of the center section of the top surface; w is half of the width of the top surface of the wide fill body (w≥H); m is the reciprocal of the slope (1.5≤m≤2); H is the fill height of the wide fill body (H≥20m), which generally refers to the fill height at its center line, including the equivalent soil column height when a static load acts on the top surface of the fill body.

[0054] The calculation result for the horizontal ground is multiplied by the correction coefficient ξ to obtain the correction value of half the width of the center section of the top surface, that is:

[0055] b c =ξb;

[0056] Where b c is the correction value of half the width of the central section of the top surface; ξ is the correction coefficient, which changes with the horizontal inclination angle α of the bottom surface of the wide fill body. When α≤5°, ξ=1; when α=10°, ξ=0.5; when α=15°, ξ=0.3; in other cases, ξ is calculated according to α using the linear difference method.

[0057] For the central area of ​​a wide fill body, due to the constraints of the surrounding large-scale fill, there will be no lateral large deformation problem, but it will show the deformation characteristics of a "lateral constraint body", that is, vertical settlement deformation is the main method, so the reinforcement of this area adopts the method of controlling vertical settlement deformation. Preferably, the central area is compacted and reinforced by the strong tamping method, and the foundation of the lower part of the central area is reinforced by a pile foundation composite foundation or the strong tamping method.

[0058] 2. Slope area

[0059] For a wide fill body, it can be regarded as a homogeneous soil slope with the potential sliding body located inside the fill body. The range of the slope area is the intercept of the potential sliding body at the top surface of the fill body as its top width. A line parallel to the slope surface (named as the inner slope surface) is drawn downward until it intersects the ground or the top surface of the wide platform below. The area enclosed by it is the slope area.

[0060] The width of the outer section of the top surface is calculated by the plastic limit analysis method or the limit equilibrium method. The theoretical value of the intercept of the potential sliding body of the wide fill body with different filling heights on the top surface of the wide fill body is calculated by the plastic limit analysis method or the limit equilibrium method. All the obtained theoretical values ​​are subjected to curve fitting, and the expression of the width of the outer section of the top surface can be obtained as follows:

[0061]

[0062] Where, L is the width of the outer section of the top surface; m is the inverse of the slope; β is the slope angle of the wide fill body; H is the fill height of the wide fill body; γ is the weight of the fill soil; c is the cohesion of the fill soil; is the internal friction angle of fill soil.

[0063] For the slope area of ​​the wide fill body, there are problems of lateral sliding stability and lateral deformation because there is no constraint on the side. Especially under the condition of super-high filling, the stability and lateral deformation problems are particularly prominent. Therefore, the reinforcement of this area adopts the method of controlling stability and lateral deformation. Preferably, the slope area is reinforced with anti-slide pile structure, reinforced soil structure or retaining wall structure.

[0064] 3. Transition Zone

[0065] The transition zone is a wide fill area excluding the central area and the slope area. The calculation expression for the width of the top transition section of the transition zone is:

[0066] S=wb c -L;

[0067] Where S is the width of the top transition section; w is half the width of the top surface of the wide fill body; L is the width of the outer section of the top surface; b c is the correction value of half the width of the center section of the top surface. If S<0 is calculated, then b is taken c =wL,S=0.

[0068] The transition zone is located in the transition interval from the area dominated by settlement deformation to the area dominated by lateral deformation. Since the outer side is constrained by the backfill of the slope area, there is generally no stability problem, but there are vertical settlement and certain lateral deformation problems. Therefore, the reinforcement of this area adopts a method that combines the control of vertical settlement as the main method and lateral deformation as the auxiliary method. Preferably, the transition zone is reinforced by combining reinforced soil structure with strong compaction method.

[0069] The beneficial effects of the present invention are described below through specific embodiments.

[0070] Example 1

[0071] The relevant parameters of the wide fill body on a certain horizontal ground (i.e. the horizontal inclination angle α of the bottom surface of the wide fill body is 0) are shown in Table 1.

[0072] Table 1

[0073]

[0074] Substituting the parameters into the formula we get:

[0075]

[0076] Taking ξ=1, we can get b c =1×30.6=30.6m;

[0077]

[0078] Thus, L = 9.07m;

[0079] S = 40-30.6-9.07 = 0.33m;

[0080] The partitioning result obtained is as follows Figure 3 shown.

[0081] Example 2

[0082] The relevant parameters of a wide fill body with an inclined bottom are shown in Table 2.

[0083] Table 2

[0084]

[0085] Substituting the parameters into the formula we get:

[0086]

[0087] Taking ξ=0.3, we can get b c =0.3×35.85=10.76m;

[0088]

[0089] Thus, L = 7.99m;

[0090] S = 40-10.76-7.99 = 21.25m;

[0091] The partitioning result obtained is as follows Figure 4 shown.

[0092] For Examples 1 and 2, the intercepts of the potential sliding bodies on the top surface of the wide fill body obtained by the classical upper limit method of plastic limit analysis were 8.25m and 8.12m respectively, and the absolute values ​​of the relative deviations between the calculation results of the method of the present invention and the above results were 9.9% and 1.6% respectively.

[0093] After analyzing the stress field of the fill body by the FLAC3D numerical simulation method, the half widths determined by the method that the ratio of the average vertical shear stress to the average vertical normal stress along the wide fill body is not greater than 10% are 33.2m and 9.8m respectively. The absolute values ​​of the relative deviations between the calculation results of the method of the present invention and the half widths are 7.8% and 9.8% respectively.

[0094] In summary, it can be seen that the calculation result deviation between the method of the present invention and the traditional method is within 10%, which is acceptable in actual engineering and is reasonable.

[0095] The above is a description of the relevant contents of the present invention. A person skilled in the art will be able to implement the present invention based on these descriptions. Based on the above contents of the present invention, all other embodiments obtained by a person skilled in the art without creative work shall fall within the scope of protection of the present invention.

Claims

1. A zoning method for reinforcement control of wide fill bodies on the ground, characterized by: The fill body is divided into a central area and a transition area and slope area on both sides of the central area. The central area is surrounded by the top surface central section, the vertical surfaces located on both sides of the top surface central section and the bottom surface central section, wherein the top surface central section overlaps with the width centerline of the top surface of the wide-width fill body; the width of the top surface central section is the width of the area in which the ratio of the average shear stress in the vertical direction to the average vertical normal stress in the wide-width fill body is not greater than 10%; The slope area is surrounded by the outer section of the top surface, the outer section of the bottom surface, the outer slope surface and the inner slope surface, wherein the outer slope surface and the inner slope surface are parallel; the width of the outer section of the top surface is the intercept of the potential sliding body on the top surface of the wide fill body; The area excluding the central area and the slope area is the transition zone.

2. The zoning method for reinforcement control of wide fill on the ground as claimed in claim 1 is characterized by: The width of the central section of the top surface is calculated using a numerical simulation method.

3. The zoning method for reinforcement control of wide fill on the ground as claimed in claim 2 is characterized by: The stress field distribution of the wide fill body is obtained by FLAC3D simulation, and then the width of the area where the ratio of the average vertical shear stress to the average vertical normal stress in the wide fill body is not greater than 10% can be determined, which is the width of the top center section. Numerical simulation analysis was performed on wide fill volumes with different fill heights and top surface widths to obtain the corresponding theoretical values ​​of the center section width. Curve fitting was performed on all the obtained theoretical values, and the expression for half of the top surface center section width was obtained as follows: In the formula, b is half of the width of the center section of the top surface; w is half of the width of the top surface of the wide fill body; m is the inverse of the slope; and H is the fill height of the wide fill body.

4. The zoning method for reinforcement control of a wide fill body on the ground as claimed in claim 3 is characterized by: The calculation result for the horizontal ground is multiplied by the correction coefficient ξ to obtain the correction value of half the width of the center section of the top surface, that is: b c =ξb; Where b c is the correction value of half the width of the central section of the top surface; ξ is the correction coefficient, which changes with the horizontal inclination angle α of the bottom surface of the wide fill body. When α≤5°, ξ=1; when α=10°, ξ=0.5; when α=15°, ξ=0.3; in other cases, ξ is calculated according to α using the linear difference method.

5. The zoning method for reinforcement control of a wide fill body on the ground as claimed in claim 1 is characterized in that: The central area is compacted and reinforced by the strong tamping method, and the foundation below the central area is reinforced by pile foundation composite foundation or strong tamping method.

6. The zoning method for reinforcement control of wide fill on the ground as claimed in claim 1 is characterized by: The width of the outer section of the top surface is calculated by using the plastic limit analysis method or the limit equilibrium method.

7. The zoning method for reinforcement control of a wide fill body on the ground as claimed in claim 6 is characterized by: The theoretical values ​​of the intercepts of the potential sliding bodies of wide fill bodies with different filling heights on the top surface of the wide fill body are calculated by using the plastic limit analysis method or the limit equilibrium method. All the obtained theoretical values ​​are curve fitted, and the expression of the width of the outer section of the top surface can be obtained as follows: Where, L is the width of the outer section of the top surface; m is the inverse of the slope; β is the slope angle of the wide fill body; H is the fill height of the wide fill body; γ is the weight of the fill soil; c is the cohesion of the fill soil; is the internal friction angle of fill soil.

8. The zoning method for reinforcement control of wide fill on the ground as claimed in claim 1 is characterized by: The slope area is reinforced with anti-slide pile structure, reinforced soil structure or retaining wall structure.

9. The zoning method for reinforcement control of a wide fill body on the ground as claimed in claim 1 is characterized by: The calculation expression of the top transition section width of the transition zone is: S=w-b c -L; Where S is the width of the top transition section; w is half the width of the top surface of the wide fill body; L is the width of the outer section of the top surface; b c is the correction value of half the width of the center section of the top surface. If S<0 is calculated, then b is taken c =wL,S=0.

10. The zoning method for reinforcement control of wide fill on the ground as claimed in claim 1, characterized in that: The transition zone is reinforced by combining reinforced soil structure with dynamic compaction method.

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