Construction process of reinforced slope

Abstract

The application discloses a construction process of a reinforced slope, belongs to the technical field of reinforced structures, and aims at at least one problem of horizontal deformation of a slope protection layer and insufficient reinforcement effect of a reinforcing material caused by the lateral earth pressure of a reinforced soil structure directly acting on the slope protection layer in the prior art. The process comprises the following steps: laying a reinforced bottom layer, and forming steps and grooves on the upper surface of the reinforced bottom layer; placing an L-shaped mesh at the end of the reinforced bottom layer far from an existing steep slope, and laying a layer of reinforcing material; forming a geotextile bag assembly at the end of the reinforcing material far from the existing steep slope; wrapping the reserved part of the reinforcing material on the geotextile bag assembly; forming a stone arrangement assembly between the geotextile bag assembly and the L-shaped mesh, and obtaining a reinforced inner layer; and forming steps and grooves on the upper surface of the reinforced inner layer. The application can be used for the construction of a reinforced slope.

Description

Technical Field

[0001] This invention belongs to the field of reinforced structure technology, and particularly relates to a construction process for reinforced slopes. Background Technology

[0002] In existing reinforced slopes, the reinforced soil is in direct contact with the slope protection layer. The lateral earth pressure generated by the reinforced soil acts directly on the slope protection layer, causing horizontal deformation. If the horizontal deformation is too large, it can easily lead to the failure of the slope protection layer, affecting the structural safety, stability, and engineering application.

[0003] In addition, the method of laying reinforcement materials also affects the safety and stability of reinforced soil structures. If the reinforcement materials are not properly pre-tensioned during the laying process, the reinforcement effect of the reinforcement materials will be insufficient, which will have an adverse effect on the long-term working performance of the reinforced soil structure. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a construction process for reinforced slopes to solve at least one of the following problems in the prior art: the lateral earth pressure generated by the reinforced soil in the reinforced soil structure directly acts on the slope protection layer, causing horizontal deformation of the slope protection layer, and the reinforcement effect of the reinforcement material is insufficient.

[0005] The objective of this invention is mainly achieved through the following technical solutions:

[0006] This invention provides a construction process for reinforced slopes, comprising the following steps:

[0007] Step 1: Lay a reinforced base layer on the existing foundation soil, and form steps and grooves on the upper surface of the reinforced base layer by compaction and excavation;

[0008] Step 2: Place the L-shaped mesh at the end of the reinforced bottom layer away from the existing steep slope, lay a layer of reinforcing material, and leave the reinforcing material for the reverse wrapping part;

[0009] Step 3: Place geotextile bags at the end of the reinforcing material away from the existing steep slope, and fill the gaps between the geotextile bags with graded crushed stone to form geotextile bag components.

[0010] Step 4: Wrap the reserved reinforcement material inside out onto the geotextile bag assembly;

[0011] Step 5: Fill the space between the geotextile bag assembly and the L-shaped mesh with graded crushed stone to form a stone-filled assembly, resulting in a reinforced inner layer. Steps and grooves are formed on the upper surface of the reinforced inner layer by compaction and excavation.

[0012] Step 6: Repeat steps 3 to 5 until all the reinforced inner layers are laid;

[0013] Step 7: Lay a reinforced surface layer on the surface of the top reinforced inner layer to obtain a reinforced steep slope;

[0014] Step 8: Construct a slope protection layer on the reinforced steep slope to complete the overall construction of the reinforced soil steep slope.

[0015] Furthermore, the following steps are included before step 1:

[0016] Determine the minimum safety factor for unreinforced steep slopes;

[0017] The vertical spacing of the reinforcing materials and the backfill length are determined based on the minimum safety factor for unreinforced steep slopes.

[0018] Furthermore, determining the minimum safety factor for an unreinforced steep slope involves the following steps:

[0019] Step a: Calculate the allowable strength of the reinforcement material, delineate the critical zone of the potential sliding surface of the steep slope, and preliminarily determine the minimum safety factor of the unreinforced steep slope;

[0020] Step b: For each sliding surface in the critical zone, calculate the total tensile force and maximum tensile force of the reinforcing material required per meter at the interface with the sliding surface;

[0021] Step c: Compare the total tensile force of the reinforcing material required at the interface with the sliding surface with the maximum tensile force of the reinforcing material;

[0022] If the two are comparable and there is no difference in magnitude, it indicates that the minimum safety factor for the unreinforced steep slope is reasonably determined.

[0023] If there is a difference of orders of magnitude between the two, it indicates that the initial determination of the minimum safety factor for the unreinforced steep slope is unreasonable, and step d should be performed.

[0024] Step d: After re-determining the minimum safety factor for the unreinforced steep slope, repeat steps b to c until the total tensile force T of the reinforcement material required at the interface with the sliding surface is reached. s It is comparable to the maximum tensile strength of the reinforced material, with no difference in magnitude.

[0025] Furthermore, in step a, the formula for calculating the allowable strength of the reinforcing material is as follows:

[0026]

[0027] In the formula: T al T represents the allowable tensile strength of the reinforcing material, in kN / m. ult R represents the ultimate tensile strength of the reinforced material, in kN / m. fID R is the construction damage reduction factor. fCR R is the creep reduction factor. fD This is the durability reduction factor.

[0028] Furthermore, in step a, delineating the critical zone of the potential sliding surface of the steep slope includes the following steps:

[0029] Draw all sliding surfaces on the steep slope cross-section diagram, calculate the safety factor of the unreinforced steep slope corresponding to all sliding surfaces, and the area enclosed by the envelope of all sliding surfaces whose safety factor of the unreinforced steep slope is equal to the required safety factor of the reinforced steep slope is the critical zone.

[0030] Furthermore, the safety factor of the unreinforced steep slope corresponding to all sliding surfaces was calculated using the Bishop method.

[0031] Further, determining the vertical spacing of the reinforcing materials includes the following steps:

[0032] Preliminary determination of the vertical spacing of the reinforcement materials for the reinforced slope;

[0033] Calculate the tensile force on each layer of reinforcement material based on the vertical spacing of the reinforcement material in the reinforced slope;

[0034] The strength calculation of the reinforcing material must meet the following requirements:

[0035] T j ≤R c T al

[0036] In the formula: T j R is the tensile force on the j-th layer of reinforcing material, kN / m; c For the coverage of reinforcing material; T al The allowable tensile strength of the reinforcing material is expressed in kN / m.

[0037] If it meets the requirements, it indicates that the vertical spacing of the reinforcement materials for the preliminarily determined reinforced slope is reasonable;

[0038] If it does not meet the requirements, the vertical spacing of the reinforcing materials should be redefined and the calculations recalculated.

[0039] Furthermore, the following steps are included before step 1:

[0040] The original foundation soil was excavated, cleaned, and leveled in sequence.

[0041] Furthermore, in step 2, when laying the reinforcing material, it is fixed with wooden wedges or U-shaped nails every 1.5 to 2.0m, and the longitudinal direction of the reinforcing material is perpendicular to the slope surface.

[0042] Furthermore, in step 3, adjacent layers of geotextile bags are stacked in an alternating manner.

[0043] Compared with the prior art, the present invention can achieve at least the following beneficial effects:

[0044] The reinforced slope obtained by the construction process of the reinforced slope provided by this invention has the characteristics of high rigidity, small deformation, and good seismic resistance. The stress of the reinforcing material is more reasonable, the reinforced slope is more stable, and the long-term working performance is better. It can give full play to the functions of different reinforcing materials, which not only conforms to the concept of environmental protection, but is also more economical. The construction method is quick and simple, and the service life of the reinforced slope is extended.

[0045] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0046] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0047] Figure 1 This is a schematic diagram showing the location of design parameters in the construction process of the reinforced slope provided in Embodiment 1 of the present invention;

[0048] Figure 2 This is a schematic diagram of the critical zone in the construction process of the reinforced slope provided in Embodiment 1 of the present invention;

[0049] Figure 3 This is a schematic diagram illustrating the determination of the total tensile force of the reinforcing material required per linear meter at the interface with the sliding surface in the construction process of the reinforced slope provided in Embodiment 1 of the present invention.

[0050] Figure 4 This is a calculation diagram for determining the maximum tensile force of the reinforcing material in the construction process of the reinforced slope provided in Embodiment 2 of the present invention;

[0051] Figure 5 This is a schematic diagram of the reinforced slope structure obtained by the construction process of the reinforced slope provided in Embodiment 1 of the present invention;

[0052] Figure 6 This is a schematic diagram of the cross-section of the reinforcing material in the construction process of the reinforced slope provided in Embodiment 1 of the present invention.

[0053] Figure label:

[0054] 1-Slope protection layer; 2-Rock-filling component; 3-L-shaped mesh; 4-Existing steep slope; 5-Geotextile bag component; 6-Reinforcing material; 61-First horizontal section; 62-First downward sloping section; 63-Second horizontal section; 64-First upward sloping section; 65-Third horizontal section; 66-Second upward sloping section; 67-Fourth horizontal section; 68-Upward folding section; 69-First reverse horizontal section; 610-Downward folding section; 611-Second reverse horizontal section; 7-Reinforced soil; 8-Drainage component; 9-Hook. Detailed Implementation

[0055] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of the present invention and are used together with the invention to illustrate the principles of the invention.

[0056] Example 1

[0057] This embodiment provides a construction process for reinforced slopes, which adopts a layered construction method from bottom to top. Specifically, the construction process includes the following steps:

[0058] Step 1: Measure and lay out the existing foundation soil and draw the slope line. Lay a reinforced bottom layer on the existing foundation soil and form steps and grooves on the upper surface of the reinforced bottom layer by compaction and excavation.

[0059] Step 2: Place the L-shaped mesh 3 at the end of the reinforced bottom layer away from the existing steep slope. Cut and lay a layer of reinforcing material 6 according to the design standards. Leave enough reverse wrapping part of the reinforcing material 6 outside the slope line. When laying the reinforcing material 6, it needs to be manually tightened and straightened. Fix it with wooden wedges or U-shaped nails every 1.5 to 2.0m. The longitudinal direction (the direction of greater strength) of the reinforcing material 6 is perpendicular to the slope surface. Generally, it should not overlap, curl or twist.

[0060] Step 3: Place geotextile bags at the end of the reinforcing material 6 away from the existing steep slope, and fill the gaps between the geotextile bags with graded crushed stone to form geotextile bag assembly 5.

[0061] Step 4: Wrap the reserved reinforcement material 6 inside out onto the geotextile bag assembly 5, and fix the wrapped end;

[0062] Step 5: Fill the space between the geotextile bag component 5 and the L-shaped mesh 3 with graded crushed stone to form the stone-filled component 2, thus obtaining a reinforced inner layer. Steps and grooves are formed on the upper surface of the reinforced inner layer by compaction and excavation.

[0063] Step 6: Repeat steps 3 to 5 until all the reinforced inner layers are laid;

[0064] Step 7: Lay a reinforced surface layer and a waterproof layer on the surface of the top reinforced inner layer to obtain a reinforced steep slope;

[0065] Step 8: Construct slope protection layer 1 on the reinforced steep slope to complete the overall construction of the reinforced slope.

[0066] Compared with existing technologies, the reinforced slope obtained by the construction process of the reinforced slope provided in this embodiment has the characteristics of high rigidity, small deformation, and good seismic resistance. The stress of the reinforcing material 6 is more reasonable, the reinforced slope is more stable, and the long-term working performance is better. It can give full play to the functions of different reinforcing materials 6, which not only conforms to the concept of environmental protection, but is also more economical. The construction method is quick and simple, and the service life of the reinforced slope is extended.

[0067] On the one hand, during construction, the steps and grooves allow for further tensioning of the reinforcing material 6 by the reinforced soil 7, maximizing the reinforcing effect of the reinforcing material 6. On the other hand, the steps and grooves increase the connection strength between the reinforcing material 6 and the reinforced soil 7, reducing the density of the reinforcing material 6 and thus reducing the amount of reinforcing material 6 used while ensuring the overall structural strength of the reinforced composite. Furthermore, the reinforcing material 6 is laid in the reinforced soil 7 and wrapped around the geotextile bag assembly 5. One end of the hook 9 is hung on the side of the L-shaped mesh 3, and the other end is buried in the slope protection layer 1. This connects the reinforced composite, the deformation energy absorption zone, and the slope protection layer 1 into a whole, thereby enhancing the integrity of the reinforced steep slope structure and further reducing the deformation of the slope protection layer 1.

[0068] For example, the reinforced slope obtained by the above construction method, see the specific structure below. Figure 5It includes a reinforced bottom layer, a reinforced surface layer, and multiple reinforced inner layers. The reinforced bottom layer, multiple reinforced inner layers, and reinforced surface layer are stacked vertically from top to bottom. The reinforced inner layer includes a slope protection layer 1, a deformation energy absorption zone, and a reinforced composite. The reinforced composite, deformation energy absorption zone, and slope protection layer 1 are arranged sequentially in a direction gradually moving away from the existing steep slope 4. The deformation energy absorption zone includes an L-shaped mesh 3, a stone-filled component 2, and a hook 9. The reinforced composite includes reinforced soil 7, reinforced material 6, and geotextile bag components 5. The geotextile bag assembly 5 is placed in the reinforced soil 7 and located on the side of the reinforced soil 7 away from the existing steep slope 4. The reinforcing material 6 is laid in the reinforced soil 7 and wraps the geotextile bag assembly 5. The geotextile bag assembly 5 is pressed on the bottom edge of the L-shaped mesh 3 and has a gap with the side edge of the L-shaped mesh 3. The side edge of the geotextile bag assembly 5, the bottom edge of the L-shaped mesh 3 and the side edge of the L-shaped mesh 3 form a stone-filling space. The stone-filling assembly 2 is filled in the stone-filling space. One end of the hook 9 is hung on the side edge of the L-shaped mesh 3 and the other end is buried in the slope protection layer 1. The reinforced slope structure described above has two advantages. First, a deformation energy absorption zone is set between the reinforced composite and the slope protection layer 1. During the construction of the steep slope 4, there is horizontal earth pressure, i.e., a thrust in the slope direction. The stone-filled component 2 can absorb part of the horizontal earth pressure, and the remaining horizontal earth pressure can be transmitted to the slope protection layer 1 through the L-shaped mesh 3 and offset and dissipated, thereby improving the overall energy absorption capacity. Second, the setting of the deformation energy absorption zone can avoid direct contact between the reinforced composite and the slope protection layer 1, effectively alleviating the deformation caused by the lateral earth pressure of the reinforced soil 7.

[0069] For example, for the structure of the reinforcing material 6, see Figure 6Along a direction gradually moving away from the existing steep slope 4, it includes, in sequence, a first horizontal segment 61, a first downsloping segment 62, a second horizontal segment 63, a first upsloping segment 64, a third horizontal segment 65, a second upsloping segment 66, a fourth horizontal segment 67, an upturned segment 68, a first reverse horizontal segment 69, a downturned segment 610, and a second reverse horizontal segment 611. The second upsloping segment 66 is located on the side of the potential sliding surface of the steep slope away from the existing steep slope 4, and the angle between the second upsloping segment 66 and the horizontal plane is 30° to 90°. Thus, the first downward sloping section 62, the second horizontal section 63, and the first upward sloping section 64 form a groove, into which the reinforced soil 7 is filled, forming a first friction-enhancing structure. The third horizontal section 65, the second upward sloping section 66, and the fourth horizontal section 67 form a stepped surface, forming a second friction-enhancing structure. The fourth horizontal section 67, the upward folding section 68, the first reverse horizontal section 69, the downward folding section 610, and the second reverse horizontal section 611 enclose a geotechnical containment space, in which the geotextile bag assembly 5 is placed. Because the second upward sloping section 66 is on the side of the steep slope's potential sliding surface away from the existing steep slope 4, it can strengthen the interface between the reinforced material 6 and the reinforced soil 7, enhance the pull-out resistance of the reinforced material 6, fully utilize the high strength characteristics of the reinforced material 6, and further reduce the deformation of the reinforced slope.

[0070] In order to improve the overall rationality of the reinforced slope, the following steps are included before step 1:

[0071] Determine the minimum safety factor for unreinforced steep slopes;

[0072] The vertical spacing and backfill length of the reinforcing material 6 are determined based on the minimum safety factor of the unreinforced steep slope.

[0073] Specifically, determining the minimum safety factor for an unreinforced steep slope involves the following steps:

[0074] Step a: Determine the geometry, load conditions, and functional requirements of the reinforced slope based on the actual site conditions (e.g., for building construction, railway, or highway).

[0075] The engineering properties and parameters of the reinforced soil fill, foundation soil, and groundwater level are determined based on engineering surveys and relevant laboratory tests. (See [reference needed]). Figure 1 ;

[0076] Calculate the allowable strength T of the reinforcing material 6. al The calculation formula is as follows:

[0077]

[0078] In the formula: T al The allowable tensile strength of reinforcing material 6 is kN / m; T ult R represents the ultimate tensile strength of reinforcing material 6, in kN / m. fIDR is the construction damage reduction factor. fCR R is the creep reduction factor. fD This is the durability reduction factor;

[0079] The critical zone of the potential sliding surface of the steep slope was delineated, and the minimum safety factor of the unreinforced steep slope was initially determined.

[0080] Plot all sliding surfaces on the steep slope cross-section diagram. Calculate the safety factor of the unreinforced steep slope corresponding to all sliding surfaces using the Bishop method. The region enclosed by the envelopes of all sliding surfaces whose safety factor for the unreinforced steep slope is equal to the required safety factor for the reinforced steep slope is the critical zone. (See [link to relevant documentation]). Figure 2 ;

[0081] It should be noted that if the critical zone extends below the toe of the slope, it indicates that deep sliding will occur. This situation involves the bearing capacity of the foundation and requires foundation stability analysis and foundation treatment. Existing methods can be used for specific analysis and treatment, which will not be elaborated here.

[0082] The minimum safety factor F for the unreinforced steep slope is initially determined from the safety factors corresponding to all sliding surfaces. urf And the critical sliding surface, requiring a minimum safety factor F for unreinforced steep slopes. urf ≤ Safety factor F required for reinforced steep slopes rf The required safety factor for reinforced steep slopes is determined based on the actual situation. The critical slip surface refers to the minimum safety factor F for an unreinforced steep slope within the critical zone. urf The corresponding sliding surface.

[0083] Step b: Calculate the maximum tensile force of the reinforcing material 6.

[0084] Step b1: For each sliding surface within the critical zone, calculate the total tensile force required per meter of reinforcing material at the interface with the sliding surface, see [reference needed]. Figure 3 The calculation formula is as follows:

[0085]

[0086] In the formula: T s To account for pull-out and pull-out, the required reinforcement material at the interface with the sliding surface is 6 times the total tensile force, kN / m; F rf Safety factor required for reinforced steep slopes; F urf M represents the minimum safety factor for an unreinforced steep slope. D denoted as , where is the moment of the sliding soil mass corresponding to the center of the sliding surface, in kN; D is the lever arm of the total tensile force of the reinforcing material 6 relative to the center of the sliding surface, in meters.

[0087] For continuous sheet-like distributed extensible reinforcing material 6 or continuous sheet-like distributed rigid mesh reinforcing material 6, it is assumed that D = R, where R is the radius of the critical sliding surface arc, in meters. For dispersed strip-like reinforcing material 6, it is first assumed that the critical sliding surface is at 1 / 3 of the slope height of the steep slope, in which case D = Y, where Y is the vertical distance from the center of the critical sliding surface to the reinforcing material 6, in meters. Alternatively, it is assumed that the reinforcing material 6 is tangent to the sliding surface only when a large slip occurs on a steep slope. In this case, it is not necessary to distinguish between extensible and rigid reinforcing material 6; it is sufficient to assume that the reinforcing material 6 is horizontally distributed, and D = Y, where Y is the vertical distance from the center of the critical sliding surface to the reinforcing material 6, in meters.

[0088] Step b2: Calculate the maximum tensile force T of the reinforcing material 6. smax The calculation formula is as follows:

[0089] T smax =0.5Kγ r (H′) 2

[0090]

[0091] In the formula: T smax q represents the maximum tensile force of reinforced material 6, in kN / m; K represents the tensile force coefficient of reinforced material 6; and q represents the uniformly distributed surcharge on the steep slope, in kN / m. 2 ;γ r The unit weight of the reinforced soil 7 in the reinforced zone is kN / m. 3 H represents the height of the steep slope, in meters.

[0092] In the above formula, K is determined using the following method:

[0093] The internal friction angle of the reinforced soil 7 within the reinforced zone (i.e., the area in the reinforced soil 7 where the reinforcing material 6 is arranged) is converted:

[0094]

[0095] In the formula: The internal friction angle of the reinforced soil is 7° after conversion; The internal friction angle of the fill in the reinforced zone is °;

[0096] See the calculation diagram for determining the maximum tensile force of the reinforced material 6. Figure 4 The tensile coefficient K of the reinforcing material 6 is determined based on the converted internal friction angle of the reinforced soil 7.

[0097] Step c: Compare the required reinforcement material at the interface with the sliding surface and the total tensile force T. s And the maximum tensile force T of the reinforcing material 6 smaxIf the two are comparable and there is no difference in magnitude, it indicates that the initial determination of the minimum safety factor for the unreinforced steep slope is reasonable. If there is a difference in magnitude, it indicates that the initial determination of the minimum safety factor for the unreinforced steep slope is unreasonable, and step d should be performed.

[0098] Step d: After re-determining the minimum safety factor for the unreinforced steep slope, repeat steps b to c until the required reinforcement material T at the interface with the sliding surface is reached. s And the maximum tensile force T of the reinforcing material 6 smax They are comparable; there is no difference in magnitude.

[0099] The steps for determining the vertical spacing of the reinforcing material 6 are as follows:

[0100] Preliminary determination of the vertical spacing of the reinforcement materials for the reinforced slope;

[0101] Based on the vertical spacing of the reinforcement material 6 in the reinforced slope, calculate the tensile force T on each layer of reinforcement material 6. j :

[0102]

[0103] In the formula: T j The tensile force (T) on the j-th layer of reinforcing material 6 is given in kN / m. z The tensile force (kN / m) on the reinforcing material 6 in each reinforced region; H z Height of each reinforced zone, m; S v , where is the vertical spacing of the reinforcing material 6, in meters; N is the number of layers of reinforcing material 6 in each reinforcing zone.

[0104] The strength calculation of the reinforcing material 6 meets the following requirements:

[0105] T j ≤R c T al

[0106] In the formula: R c For the coverage of the reinforcing material 6, for the continuous sheet-like reinforcing material 6R c =1, for strip-reinforced material 6, R c Equals the width b of the reinforcing material 6 divided by the horizontal spacing S h ;

[0107] If it meets the requirements, it indicates that the vertical spacing of the reinforcement material 6 in the preliminarily determined reinforced slope is reasonable;

[0108] If it does not meet the requirements, the vertical spacing of the reinforcing material 6 should be redefined and the calculation should be recalculated.

[0109] It should be noted that if the steep slope height H ≤ 6m, then the number of reinforced zones is one, T zEqual to the maximum tensile force T of the reinforced material 6 smax The maximum tensile force T of the reinforcing material 6 smax The reinforcement material 6 is evenly distributed to each layer with equal spacing; if the steep slope height H > 6m, the maximum tensile force T of the reinforcement material 6 is calculated. smax The steep slope is divided into 2-3 reinforced zones of equal height along the slope. The reinforcing material 6 is arranged at equal intervals in each reinforced zone. The tensile force Tz on the reinforcing material 6 in each reinforced zone is considered as follows:

[0110] For example, if the steep slope height H ≤ 6m, then the number of reinforced zones is one, T z Equal to the maximum tensile force T of the reinforced material 6 smax The maximum tensile force T of the reinforcing material 6 smax The reinforcing material 6 is evenly distributed to each layer with equal spacing;

[0111] If the steep slope height H > 6m, then it is divided into a first reinforcement zone and a second reinforcement zone from top to bottom along the vertical direction. In the first reinforcement zone, T z =(3 / 4)T smax T in the second reinforced zone z =(1 / 4)T smax Alternatively, it can be divided vertically from top to bottom into a first reinforced zone, a second reinforced zone, and a third reinforced zone, where T in the first reinforced zone... z =(1 / 2)T smax T in the second reinforced zone z =(1 / 3)T smax T in the third reinforced zone z =(1 / 6)T smax ;

[0112] In each reinforced zone, the tensile force T on the reinforcing material 6 is... z The reinforcing material 6 is evenly distributed to each layer of equally spaced reinforcement materials.

[0113] The above-mentioned determination of the filling length of the reinforcing material 6 includes the following steps:

[0114] The initial length of the reinforcing material 6 to be buried was determined;

[0115] According to T smax The corresponding sliding surface serves as the interface for anchoring the reinforcing material 6. The pull-out force T of each layer of reinforcing material 6 is calculated. pj :

[0116] T pj =2f GS βR c [σ v1j L e1j +W 2j cosα+σ v3j Le3j ]+W 2j sinα

[0117]

[0118] In the formula: T pj The pull-out resistance of the j-th layer of reinforcing material is given by f (kN / m). GS The pull-out resistance coefficient (interfacial friction coefficient) is determined experimentally or obtained from a semi-empirical formula. β is the nonlinear distribution effect coefficient considering the interaction between the reinforcing material 6 and the soil; 0.8 is taken for the geogrid reinforcing material 6, and 0.6 is taken for the geotextile reinforcing material 6; R c To achieve the required reinforcement coverage, for continuous sheet-like reinforced materials 6R... c =1, for strip-reinforced material 6, R c Equals the width b of the reinforcing material 6 divided by the horizontal spacing S h ;σ v1j The stress is the self-weight stress acting on the fourth horizontal segment 67 of the j-th layer, in kPa; σ v3j Let L be the self-weight stress acting on the first horizontal segment 61, the first downward sloping segment 62, the second horizontal segment 63, the first upward sloping segment 64, and the third horizontal segment 65 of the j-th layer, in kPa; e1j L is the embedment length (m) of the fourth horizontal segment 67 of the j-th layer within the passive zone near the existing slope of the sliding surface. e2j L is the embedment length (m) of the second upward-sloping segment 66 of the j-th layer within the passive zone near the existing slope of the sliding surface. e3j W represents the embedment length (m) of the first horizontal segment 61, the first downward sloping segment 62, the second horizontal segment 63, the first upward sloping segment 64, and the third horizontal segment 65 of the j-th layer within the passive zone near the existing slope of the sliding surface. 2j α is the weight of the soil on the second upper inclined section 66 of the j-th layer in the passive zone near the existing slope, in kN; α is the angle between the second upper inclined section 66 and the horizontal plane, in °;

[0119] The pull-out stability of reinforced material 6 conforms to the following formula:

[0120]

[0121] In the formula: F e The stability safety factor for pullout resistance of the reinforced material is Fe = 0.5 for coarse-grained soil and Fe = 2.0 for cohesive soil; T pj The pull-out resistance of the j-th layer of reinforcing material is given by T (kN / m). j The tensile force on the j-th layer of reinforcing material 6 is kN / m;

[0122] If it meets the requirements, it indicates that the preliminarily determined embedment length of the reinforcing material 6 (i.e., the embedment length of the fourth horizontal section 67 of the j-th layer in the passive zone on the side of the sliding surface close to the existing slope, the embedment length of the second upward inclined section 66 of the j-th layer in the passive zone on the side of the sliding surface close to the existing slope, and the embedment lengths of the first horizontal section 61, the first downward inclined section 62, the second horizontal section 63, the first upward inclined section 64 and the third horizontal section 65 of the j-th layer in the passive zone on the side of the sliding surface close to the existing slope) is reasonable.

[0123] If it does not meet the requirements, the vertical spacing of the reinforcing material 6 should be redefined and the calculation should be recalculated.

[0124] To ensure the flatness of the entire construction process, the following steps are included before step 1 above:

[0125] The original foundation soil was excavated, cleaned and leveled in sequence to ensure that the surface of the original foundation soil was flat, and sharp protrusions were removed to ensure that the transverse slope of the foundation soil surface was not less than 1%.

[0126] For the installation of drainage components, exemplarily, the following steps are also included between steps 3 and 4 above:

[0127] Lay and fix the grid along a direction perpendicular to the slope, then spread sand and gravel within the mesh and compact it.

[0128] In order to achieve a stable connection between the hook 9, the slope protection layer 1, and the L-shaped mesh 3, the slope protection layer 1 is made of lightweight foamed concrete. This is because lightweight foamed concrete has an adhesive effect, and the slope protection layer 1 itself can bond to the sides of the hook 9 and the L-shaped mesh 3 respectively. At the same time, in order to further improve the connection stability between the hook 9 and the L-shaped mesh 3, the deformation energy absorption zone also includes a binding member, through which the hook 9 is fixedly connected to the L-shaped mesh 3.

[0129] Specifically, the composition of the aforementioned lightweight foamed concrete, by mass percentage, includes 20-30% fly ash, 43-52% silicate cement, 0.5-1% polypropylene short fibers, 2-2.5% basalt fibers, 0.5-1.3% animal and plant protein foaming agent, 0.1-0.3% foam stabilizer, 0.4-0.9% water-reducing agent, and 12.5-34% water. The polypropylene short fibers have a diameter of 8-12 μm and a length of 6-10 mm, while the basalt fibers have a diameter of 15-30 μm and a length of 12-18 mm. The density of the lightweight foamed concrete obtained using the above components is 800-1200 kg / m³. 3The thickness of slope protection layer 1 is 100–300 mm. In this slope protection layer 1, the aggregates are industrial solid wastes such as slag, steel slag, and coal gangue (i.e., fly ash). The addition of polypropylene short fibers and basalt fibers in the concrete acts as reinforcement and bridging agents, enhancing the structural strength while inhibiting and delaying crack propagation, significantly improving the concrete's impermeability, frost resistance, and other durability properties. Compared to conventional lightweight water-resistant materials, the incorporation of polypropylene and basalt fibers strengthens the material's crack resistance while simultaneously improving its impermeability and frost resistance.

[0130] Specifically, the structure of the geotextile bag assembly 5 includes multiple layers of geotextile bags stacked vertically, with adjacent layers of geotextile bags being staggered.

[0131] To improve the drainage performance of the reinforced slope, the aforementioned reinforced slope also includes a drainage component 8. This drainage component 8 comprises a grid (e.g., a three-dimensional plastic grid system) horizontally laid within the reinforced soil 7, and sand and gravel filling the grid. The overall height of the drainage component 8 is 25–30 cm, and the vertical spacing between adjacent drainage structures is 2–3 m. The grid is a three-dimensional mesh structure composed of polyethylene strips with welded intersecting nodes and drainage holes. The strips are 5–15 cm high, and the distance between the intersecting nodes is 20–40 cm. Thus, using a three-dimensional plastic grid system as the main body of the drainage structure effectively solves the problem of internal moisture accumulation in the reinforced soil structure, prevents a decrease in the strength index of the reinforced soil 7, and thereby improves the overall stability and safe application of the reinforced soil structure.

[0132] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A construction technique for reinforced slopes, characterized in that, Includes the following steps: Step 1: Lay a reinforced base layer on the existing foundation soil, and form steps and grooves on the upper surface of the reinforced base layer by compaction and excavation; Step 2: Place the L-shaped mesh at the end of the reinforced bottom layer away from the existing steep slope, and lay a layer of reinforcing material flat, leaving a portion for wrapping back; Step 3: Place geotextile bags at the end of the reinforcing material away from the existing steep slope, and fill the gaps between the geotextile bags with graded crushed stone to form geotextile bag components. Step 4: Wrap the reserved reinforcement material inside out onto the geotextile bag assembly; Step 5: Fill the space between the geotextile bag assembly and the L-shaped mesh with graded crushed stone to form a stone-filled assembly, resulting in a reinforced inner layer. Steps and grooves are formed on the upper surface of the reinforced inner layer by compaction and excavation. Step 6: Repeat steps 3 to 5 until all the reinforced inner layers are laid; Step 7: Lay a reinforced surface layer on the surface of the top reinforced inner layer to obtain a reinforced steep slope; Step 8: Construct a slope protection layer on the reinforced steep slope to complete the overall construction of the reinforced soil steep slope; the following steps are included before Step 1: Determine the minimum safety factor for unreinforced steep slopes; The vertical spacing of the reinforcing materials and the backfill length are determined based on the minimum safety factor for unreinforced steep slopes. Determining the minimum safety factor for unreinforced steep slopes includes the following steps: Step a: Calculate the allowable strength of the reinforcement material, delineate the critical zone of the potential sliding surface of the steep slope, and preliminarily determine the minimum safety factor of the unreinforced steep slope; Step b: For each sliding surface in the critical zone, calculate the total tensile force and maximum tensile force of the reinforcing material required per meter at the interface with the sliding surface; Step c: Compare the total tensile force of the reinforcing material required at the interface with the sliding surface with the maximum tensile force of the reinforcing material; If the two are comparable and there is no difference in magnitude, it indicates that the minimum safety factor for the unreinforced steep slope is reasonably determined. If there is a difference of orders of magnitude between the two, it indicates that the initial determination of the minimum safety factor for the unreinforced steep slope is unreasonable, and step d should be performed. Step d: After re-determining the minimum safety factor for the unreinforced steep slope, repeat steps b to c until the total tensile force of the reinforcing material required at the interface with the sliding surface is reached. T s It is comparable to the maximum tensile strength of the reinforced material, with no difference in magnitude.

2. The construction process for reinforced slopes according to claim 1, characterized in that, In step a, the formula for calculating the allowable strength of the reinforcing material is as follows: In the formula: T al The allowable tensile strength of the reinforcing material is expressed in kN / m. T ult The ultimate tensile strength of the reinforcing material is expressed in kN / m. R fID This is the construction damage reduction factor. R fCR This is the creep reduction factor. R fD This is the durability reduction factor.

3. The construction process for reinforced slopes according to claim 1, characterized in that, In step a, delineating the critical zone of the potential sliding surface of the steep slope includes the following steps: Draw all sliding surfaces on the steep slope cross-section diagram, calculate the safety factor of the unreinforced steep slope corresponding to all sliding surfaces, and the area enclosed by the envelope of all sliding surfaces whose safety factor of the unreinforced steep slope is equal to the required safety factor of the reinforced steep slope is the critical zone.

4. The construction process for reinforced slopes according to claim 3, characterized in that, The safety factor of the unreinforced steep slope corresponding to all sliding surfaces was calculated using the Bishop method.

5. The construction process for reinforced slopes according to claim 1, characterized in that, Determining the vertical spacing of the reinforcing materials includes the following steps: Preliminary determination of the vertical spacing of the reinforcement materials for the reinforced slope; Calculate the tensile force on each layer of reinforcement material based on the vertical spacing of the reinforcement material in the reinforced slope; The strength calculation of the reinforcing material must meet the following requirements: In the formula: T j The tensile force on the j-th layer of reinforcing material is expressed in kN / m. R c To ensure sufficient coverage of reinforcing materials; T al The allowable tensile strength of the reinforcing material is expressed in kN / m. If it meets the requirements, it indicates that the vertical spacing of the reinforcement materials for the preliminarily determined reinforced slope is reasonable; If it does not meet the requirements, the vertical spacing of the reinforcing materials should be redefined and the calculations recalculated.

6. The construction process for reinforced slopes according to claim 1, characterized in that, The following steps are included before step 1: The original foundation soil was excavated, cleaned, and leveled in sequence.

7. The construction process for the reinforced slope according to claim 1, characterized in that, In step 2, when the reinforcing material is laid, it is fixed with wooden wedges or U-shaped nails every 1.5 to 2.0 m, and the longitudinal direction of the reinforcing material is perpendicular to the slope.

8. The construction process for reinforced slopes according to claim 1, characterized in that, In step 3, adjacent layers of geotextile bags are stacked alternately.

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