RU2276230C1 - Road embankment with retaining wall, method of retaining wall erection and reinforced concrete block for retaining wall erection - Google Patents

Abstract

FIELD: building, particularly to erect road embankments.

SUBSTANCE: road embankment comprises embankment ground, retaining wall and support structure. Embankment ground is divided with flat geonet webs into several layers. The retaining wall is also divided into layers similar to ground layers and covered with single geonet webs. Each retaining wall layer has vertical through slots filled with macroporous draining material. Flat geonet webs are inserted between hollow layers of retaining wall. Vertical cavities of adjacent retaining wall layers in height direction are superposed in plan view. Length L of ground layers reinforced with flat geonet webs beginning from inner retaining wall surface is determined from a given equation. Road embankment erection method involves forming retaining wall base; laying road embankment ground layers alternated with flat geonet webs; erecting retaining wall comprising several layers and constructing support structure. Base is initially created and then lower erection wall layer is erected on the base, wherein the retaining wall is provided with vertical cavities having heights corresponding to ground layer heights. The vertical cavities are filled with coarse material for 2/3 of volume thereof and then embankment ground layer is poured and compacted. Embankment ground is leveled and coarse material is added in the cavities. The coarse material is leveled and geonet web is placed onto the coarse material within the bounds of retaining wall and embankment ground layer. Next layers are formed in similar manner. Reinforced concrete block for retaining wall forming comprises device, which cooperates with ambient ground. The device comprises one or several vertical through cavities to be filled with granular coarse material. Depression in concrete is formed in lower block surface in front of erection loop.

EFFECT: reduced material consumption and erection time, increased service life, stability and operational reliability.

9 cl, 12 dwg

Description

The invention relates to the field of construction and can be used in the construction of road embankments.

Known retaining wall containing a monolithic front wall, on the foundation of which a concrete protrusion is made, which serves to abut the front guard against shear, an armored structure made of alternating layers of compacted drainage backfill, and geotextile interlayers (RF Patent No. 2167242, publ. 20.05.01 g.).

The disadvantage of this wall design is the lack of communication between the body of the retaining wall and the ground, i.e. the stability of the wall is determined only by the strength of the wall itself.

The closest technical solution to the claimed is a retaining wall containing a front fence, composed of wall blocks having surfaces with ribs and mating grooves facing each other in a horizontal plane, and an armored structure made in the form of layers of compacted drainage soil backfill, overlapping with reinforcing elements (RF Patent No. 2140483, publ. 10/27/99).

The disadvantage of the retaining wall of this design is that the seams between the blocks are of poor quality, leaking, thereby reducing the durability of the structure, the wall has a poor appearance, high cost and long construction time.

There is a method of constructing a road embankment with a retaining wall by forming an armored structure with reinforcement made of geotextile material or geogrids with a front fence of masonry (KD Jones "Construction of reinforced soil", M., Stroyizdat, 1989, p.175 , fig. 8.28).

The disadvantage of this method is its busyness and low technology.

The closest technical solution to the claimed is a method of erecting a bridge abutment, including the construction of a front fence from wall blocks and the simultaneous filling of layers of reinforced soil structure, consisting of layers of compacted soil, interbedded with reinforcing elements (RF Patent No. 2140483, publ. 10.27.99). .

The disadvantage of this method is that it does not allow the construction of a wall with the presence of crushed stone in the cavities of concrete blocks and does not determine the sequence of operations necessary for the construction of a road embankment with a retaining wall of the proposed design (filling cavities of blocks, laying a layer of geotextile, etc.).

Known retaining wall, made in the form of brickwork, the advantage of which is its versatility (KD Jones "Construction of reinforced soil", M., Stroyizdat, 1989, p.175, Fig. 8.28). The disadvantages of using brick in the construction of the retaining wall are the lack of its connection with the ground, i.e. the stability of the wall is determined only by the properties of the wall itself, and in the busyness of its construction.

Closest to the proposed is a concrete block retaining wall having surfaces with ribs and their corresponding grooves facing each other in the horizontal plane (RF Patent No. 2140483, publ. 10.27.99).

The disadvantage of this block lies in the large volume of concrete, reducing durability and determining the poor appearance of the construction of poor-quality joints.

The objective of the proposed invention was to reduce the material consumption of the structure, reduce construction time, increase durability while ensuring architectural requirements, stability and operational reliability of the structure.

To solve this problem, in a road embankment containing embankment soil, sprinkled on the natural surface of underlying soils and divided by flat geogrid paintings into separate layers, a retaining wall located on the side or end sides of the embankment, mounted on the foundation and adjacent to the embankment soils, the supporting structure in the form of a roadway or a bridge support plate laid directly on the embankment soil, the retaining wall is divided into layers equal to the layers of the embankment soil, each layer of the retaining wall is made it is hollow with vertical through cavities filled with large-pore drainage material, and geogrid webs are wedged between the hollow layers of the retaining wall, while the vertical cavities of the layers of retaining wall adjacent in height are aligned in plan and the length “L” of the soil layers reinforced with a flat geogrid, counting from the inside the surface of the retaining wall is determined by calculation, but it should be not less than the height of the embankment.

In addition, with a lateral symmetrical arrangement of the retaining wall, each layer of the retaining wall can be equipped with additional metal anchors.

In addition, at the end location of the retaining wall with a supporting structure in the form of a bridge abutment plate, directly under the abutment plate in the body of the embankment, an array of coarse-porous drainage material is located over its entire width, the parameters of which can be determined from the following relationships:

In _W ≥k · in, m,

Н _З ≥к · В ₃ , m,

where In ₃ - the width of the array, counting from the inner surface of the retaining wall, m;

k = 1,1 ÷ 1,5 - coefficient of local conditions, b / r;

in - the distance of the inner edge of the bridge abutment plate from the inner surface of the retaining wall, m;

H ₃ - the total height of the array, m

To solve this problem, in a method of constructing a road embankment with a retaining wall, including the operation of constructing the foundation of the retaining wall, laying the layers of soil of the embankment, each of which is limited by a flat geogrid, constructing the retaining wall from separate layers, erecting the supporting structure, after constructing the foundation, the lower a layer of retaining wall with vertical cavities corresponding in height to a layer of sprinkled soil of the embankment, after which vertical cavities are filled up with coarse material, in the morning they dig it in, then fill and tamp the bottom layer of the embankment soil, level the sprinkled soil layer and the coarse-porous material layer in the cavities of the retaining wall layer, lay the flat geogrid layer within the retaining wall layer and the embankment soil layer, and then lay the following layers of the retaining wall, embankment soil and a flat geogrid in the same sequence.

Furthermore, in the method of road embankment construction with the retaining wall, and filling ramming cavities retaining wall may carry first part by _^2/3 volume, and the final filling volume is initialized at the alignment layer of soil embankment immediately before laying flat layer of geogrid.

In addition, in the method of constructing a road embankment with a retaining wall after fabricating the retaining wall layer, filling the cavities with porous material and compacting it, the drainage layer located on the inside of the retaining wall is filled in and a flat geogrid layer is laid separating the embankment soil and the porous material.

In addition, in the method of constructing a road embankment with a retaining wall, before the operation of leveling the embankment soil and the layer of coarse-grained material, additional metal anchors can be installed in the cavities of the retaining wall layer by laying them in grooves that are open in the compacted soil layer and connecting them with embedded parts - retaining loops the walls.

To solve the problem in a reinforced concrete block of the retaining wall, the device for communication with the adjacent soil of the embankment is made in the form of one or more vertical through cavities filled with large-pore material.

, а толщина "δ" железобетонной перемычки между смежными полостями и между полостью и внешней гранью не должна быть менее 80 мм.In addition, in the reinforced concrete block of the retaining wall, the ratio of the volume of vertical cavities V _n to the volume of reinforced concrete V _b can satisfy the condition

and the thickness "δ" of the reinforced concrete lintel between adjacent cavities and between the cavity and the outer face should not be less than 80 mm.

In addition, in the reinforced concrete block for the retaining wall, the total width "in", the height "h" and the length "l" of the block are determined from the following relations:

0.4≤v≤2.0, m

0.2≤h≤1.0, m

0.4≤l≤5.0, m.

In addition, in the lower surface of the reinforced concrete block for the retaining wall opposite the mounting loop located on top, a recess can be made corresponding to the size in terms of the size of the mounting loop, the height of "h _m " which is equal to h _m = kh _n , where k = 1, 1 ÷ 1,5 - coefficient of working conditions, b / r; h _n - the height of the mounting loop, m

Also, the reinforced concrete block for the retaining wall can be equipped with embedded parts - hinges installed on the side of the block facing the embankment ground to secure metal anchors.

The essence of the invention is illustrated by drawings, where

figure 1 shows a road embankment with a side retaining wall with a supporting structure in the form of a roadway, cross section;

figure 2 shows a road embankment with a side retaining wall with a supporting structure in the form of a railway bed, cross section;

figure 3 shows the approachable part of the embankment to the bridge with an end retaining wall with a supporting structure in the form of a bridge abutment, section along the longitudinal axis of the bridge;

figure 4-10 presents the individual stages of the construction of the embankment with a retaining wall to explain an example implementation of the method of construction;

figure 11 presents a diagram of a reinforced concrete block for retaining wall, section 1-1 in figure 12;

Fig.12 is the same, a top view.

A road embankment with a retaining wall comprises embankment soil 1, retaining wall 2, and support structure 3. The embankment soil 1 along the length “L”, counting from the inner surface of retaining wall 2, is divided into layers 4 by flat geogrid webs 5. Retaining wall 2 is also divided into layers 6, which coincide with the layers 4 of the soil of the embankment and are overlain by uniform canvases of a flat geogrid 5. Each layer 6 of the retaining wall may consist of separate blocks or be monolithic made of reinforced concrete or other material. The layers of the retaining wall have vertically oriented through cavities 7, which are aligned in adjacent layers (and thus along the entire height of the wall). The cavity 7 is filled with large-pore drainage material, for example, gravel. The retaining wall 2 is installed on the foundation plate 8, which transfers pressure to the natural base 10 through a cushion 9 made of non-porous soil. On other weak soils of the base, another type of foundation is also possible, for example, pile. A case is also possible when the lower layer of the retaining wall is at the same time its foundation. In this case, additional structural measures are taken, for example, the device of a compacted soil layer under the lower wall layer. In the upper part of the retaining wall there may be a cornice block 11, a railing 12, platforms - shelters 13, etc. On the inside of the retaining wall 2, crushed stone prisms 14 can be constructed within each layer 6, and a drainage pipe 15 can be arranged in the lower prism 14.

The supporting structure 3 can be either pavement 16, or a railway bed 17, or a bridge support consisting of a sofa block 18, a transition plate 19, pavement 16, while the span 20 is supported on the sofa block 18. To increase the bearing capacity the retaining wall, the latter can be equipped with metal anchors 21 mounted on the side of the inner surface of the wall and fixed to the embedded parts 22 of the retaining wall 2.

, где L_н - расстояние между внутренними сторонами подпорных стенок. Если расположение подпорной стенки торцевое (фиг.3), и опорная конструкция представляет собой устой моста, то под плитой устоя моста на всю ширину плиты устраивают массив из крупнопористого дренирующего грунта, например, щебня. При этом размеры массива определяют из следующих зависимостей:The main parameters of a road embankment with a retaining wall are determined from the following considerations. With a lateral arrangement of the retaining wall (Fig. 1), the length "L" of embossing the panels of the flat geogrid 5 into the soil of the embankment should be not less than the height of the embankment "N": L≥N. If the retaining wall is located on both sides of the embankment (figure 2), then

where L _n - the distance between the inner sides of the retaining walls. If the location of the retaining wall is end-face (Fig. 3), and the supporting structure is a bridge abutment, then under the bridge abutment plate, an array of coarse-porous drainage soil, such as crushed stone, is arranged over the entire width of the plate. The dimensions of the array are determined from the following dependencies:

In ₃ ≥k · in, m,

Н ₃ ≥к · В ₃ , m,

where In ₃ - the width of the array, counting from the inner surface of the retaining wall, m;

k = 1,1 ÷ 1,5 - coefficient of local conditions, b / r;

in - the distance of the inner edge of the bridge abutment plate from the inner surface of the retaining wall, m;

N _W - the total height of the array, m

To ensure non-clogging gravel prisms 14, the latter are closed by a layer of a flat geogrid 23.

Road embankment with retaining wall works as follows. The vertical load from the supporting structure and the dead weight of the embankment soil is perceived by the base soil. The self-supporting weight of the retaining wall is also perceived through the foundation through the foundation. The horizontal pressure of the embankment soil from the supporting structure and the own weight of the embankment soil is perceived by flat geogrid panels laid between the layers of embankment soil and the retaining wall. In this case, the sealing of the panels of the flat geogrid 5 between the layers of the retaining wall is ensured by their engagement on crushed stone or other large-porous material located in the cavities of the layers of the retaining wall. If necessary, additional horizontal load can be absorbed by horizontal anchors 21.

A method of constructing a road embankment with a retaining wall comprises the steps of laying layers of soil of the embankment, constructing a foundation, retaining wall from separate layers and a supporting structure. First, the construction of the foundation 8 on the pillow 9 of non-porous soil is carried out. In some cases, the role of the foundation can be played by the first layer of the retaining wall. Then the operation of building the foundation, as an independent one, is simplified and reduced mainly to high-quality compaction of the soil of the base and filling of the pillow. After the construction of the foundation, the first layer of the retaining wall is constructed either from separate blocks or from monolithic reinforced concrete (Fig. 4). Each layer of the retaining wall contains vertical through cavities 7. The next step is to fill up the vertical cavities with porous material, for example, crushed stone (Fig. 5). Since the cavities of 7 adjacent layers of the retaining wall are combined, the crushed stone provides the incorporation of paintings of a flat geogrid between the layers of the retaining wall. Next, pour and compact the layer 4 of the soil of the embankment (Fig.6 and 7). Then, the soil layer of the embankment and the crushed stone layer are leveled in the retaining wall layer (Fig. 8), after which the canvases of a flat geogrid are laid on top (Fig. 9). In order for the adhesion to be sufficient, it is necessary to ensure the cleanliness of the gravel located in the cavities 7 during the construction process. This cleanliness can be impaired due to the ingress of ordinary soil during the filling of layer 4 of the embankment soil. Therefore, the filling of the cavity 7 with crushed stone is initially not carried out to full height, but is finally refilled in the process of leveling the soil layer of the embankment and the crushed stone layer of the cavity before laying a flat geogrid on top of the canvas. In some cases, the construction of crushed stone prisms 14. These prisms within each layer are constructed after the erection of layers of the retaining wall and closed with a layer of a flat geogrid 23.

If necessary, before the operation of leveling the soil of the embankment and the layer of porous material in the cavities of the retaining wall layer, additional metal anchors are installed. To do this, grooves are torn off in the compacted soil layer, the anchors are laid in them, connected to the embedded parts-loops of the retaining wall, the grooves are covered with soil and compacted.

Figure 4-10 presents an example implementation of the method. The case of construction when the retaining wall layer consists of prefabricated blocks is considered.

Figures 4 and 10 show the first operation of constructing the next layer of retaining wall and embankment soil (in Fig. 4 - the previous layer, in Fig. 10 - immediately following it). The first operation, therefore, is to install a layer 6 of the retaining wall containing vertically oriented through-cavity 7.

Figure 5 presents the following operation - filling the cavity 7 with crushed stone and its ramming. The dimensions in terms of the cavity 7 should be such as to provide the possibility of mechanized laying and ramming of crushed stone. The cavity 7 is filled to _^2/3 height.

Figure 6 shows the stage of filling gravel prism 14 and cover it with a separating layer of a flat geogrid 23.

At the next stage (Fig. 7), fill the soil of the embankment within the layer 4. Next, level the soil of the embankment layer 4 and add crushed stone to the cavity 7 (Fig. 8).

The operation of constructing a layer of the embankment with a retaining wall is completed by laying the canvas of a flat geogrid 5.

, где V_б - объем железобетона блока. При этом δ≥80 мм из условий прочности при монтаже и размеров защитного слоя бетона.The reinforced concrete block for the retaining wall is a rectangular parallelepiped (11, 12) with front 24, inner 25, lower 26, upper 27 and two side 28 surfaces. The reinforced concrete block for the retaining wall contains a device for communication with adjacent soil, which is a vertically oriented cavity 7, arranged in the body of the block, filled with loose large-porous material. The cavities 7 are through through between the lower 26 and upper 27 surfaces of the block. In terms of the cavity can have a different configuration. From the conditions of the best operation of the unit in adhesion to adjacent soil and from the conditions of minimizing weight during installation, the volume of cavities V _n should be the maximum possible. However, this is limited by other conditions, for example, the wall thickness "δ" between the surfaces of adjacent cavities or the vertical surfaces of the block 24, 25, 28. The search for the best block design showed that for different cavity configurations, the ratio

where V _b - the volume of reinforced concrete block. Moreover, δ≥80 mm from the conditions of strength during installation and the dimensions of the protective layer of concrete.

From the conditions of ease of installation and strength of the blocks during installation, the total width "in", the height "h" and the length "l" of the block are determined from the following relationships:

0.4≤v≤2.0, m

0.2≤h≤1.0, m

0.4≤l≤5.0, m.

To carry out the movement of the block with lifting devices, the block has sling loops 29 located on the upper surface 27. On the side of the lower surface 26, recesses 30 are located in the block, located directly under the sling loops 29. The dimensions of the recesses 30 correspond to the dimensions of the sling loops 29. From the conditions of guaranteed tight the connection of blocks adjacent in height, the height h _{m of the} recess 30 should be slightly greater than the height of the sling loop 29:

h _m = kh _n ,

where k = 1,1 ÷ 1,5 - coefficient of working conditions, b / r;

h _n - the height of the mounting loop, m

On the sides to the block are embedded parts 22.

Reinforced concrete block for retaining wall of the proposed design is intended for the construction of a road embankment with retaining wall, as a single system (figure 1, 2, 3).

The block is mounted on the foundation or on the block that is previous in height so that the cavities 7 of blocks adjacent in height are aligned, and the sling loops 29 enter the recesses 30. Crushed stone is poured into and into the cavity 7. Layers of a flat geogrid 5 are intended for anchoring in the ground, which extend between blocks adjacent in height and are clamped by rubble located in the cavity. Embedded parts 22 are used to secure additional anchors placed in the soil body.

The effectiveness of the proposed inventions is to reduce the material consumption of the structure, reduce construction time, increase durability while ensuring architectural requirements, stability and operational reliability of the structure.

Claims (9)

1. A road embankment with a retaining wall, containing embankment soil sprinkled on the natural surface of the underlying soil and separated by flat geogrid webs into separate layers, a retaining wall located on the side or end sides of the embankment, mounted on the foundation and adjacent to the embankment soil, and the supporting structure in the form of a roadway or a bridge support plate laid directly on the embankment soil, characterized in that the retaining wall is divided into layers equal to the layers of the embankment soil, each layer of retaining walls and is made with vertical through cavities filled with large-pore drainage material, and the flat geogrid webs are wound between the hollow layers of the retaining wall, while the vertical cavities of the height-adjacent layers of the retaining wall are aligned in plan and the length L of the soil layers reinforced by geotextile, counting from the inner surface of the retaining walls should be at least the height of the embankment. 2. The road embankment according to claim 1, characterized in that, with a symmetrical lateral arrangement of the retaining wall, each layer of the retaining wall is provided with additional metal anchors. 3. The road embankment according to claim 1, characterized in that, at the end location of the retaining wall with a supporting structure in the form of a bridge abutment plate, immediately below the abutment plate in the body of the embankment, an array of coarse-porous drainage soil is located over its entire width, the parameters of which are determined from the following relationships : In _W ≥ q N _W ≥ kV _Z , where B ₃ is the width of the array, counting from the inner surface of the retaining wall, m; k = 1,1 ÷ 1,5 - coefficient of local conditions, b / r; in - the distance of the inner edge of the bridge abutment plate from the inner surface of the retaining wall, m; N _W - the total height of the array, m 4. A method of constructing a road embankment with a retaining wall, comprising the steps of constructing a foundation of a retaining wall, laying soil layers of the embankment, each of which is limited by a geotextile fabric, constructing a retaining wall from separate layers, erecting a support structure, characterized in that after the foundation is first built on the foundation construct a layer of retaining wall with vertical cavities corresponding to the height of the soil layer, and then fill and compact the vertical cavities with porous material ohm, then the embankment soil layer is poured and compacted, the embankment soil and the coarse-porous material layer are leveled in the cavities of the retaining wall layer, the geotextile layer is laid within the retaining wall layer and the embankment soil layer, after which the next layer is laid in the same sequence. 5. The method of constructing a road embankment according to claim 4, characterized in that after manufacturing the retaining wall layer, filling the cavities with porous material and compacting it, the drainage layer located on the inside of the retaining wall is filled in and a geotextile layer is laid that separates ordinary and drainage soils . 6. The method of constructing the road embankment according to claim 5, characterized in that before the operation of leveling the embankment soil and the layer of large-porous material in the cavities of the retaining wall layer, additional metal anchors are installed by laying them in the grooves opened in the compacted soil layer and connecting them with embedded parts retaining wall loops. 7. A reinforced concrete block for a retaining wall, comprising a device for communicating with an adjacent soil, characterized in that the device for communicating with an adjacent soil is made in the form of one or more vertical through cavities filled with granular bulk material, the volume ratio of one or more vertical cavities V _n to the volume of reinforced concrete V _b satisfies the condition:

and in the lower surface of the block opposite the mounting loop located on top, a recess is made in concrete, the size in terms of which corresponds to the size of the mounting loop, and in height h _m equal h _m = kh _p where k = 1,1 ÷ 1,5 - coefficient of working conditions, b / r; h _p - the height of the mounting loop, m; 8. The reinforced concrete block according to claim 7, characterized in that the total width b, height h and length l of the block are determined from the following relationships: 0.4≤v≤2.0, m, 0.2≤h≤1.0, m, 0.4≤1≤5.0, m. 9. The reinforced concrete block according to claim 8, characterized in that from the side facing the ground, it is equipped with embedded parts-loops for attaching metal anchors.

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