RU2249071C2 - Gabion retaining wall - Google Patents

Abstract

FIELD: hydraulic structures, particularly for river or channel banks and slopes consolidation.

SUBSTANCE: wall includes gabions formed of net and stones and laid in rows. Gabions are made as parabolic cylinders oriented transversely or along flow direction and connected one to another so that gabion ridges of upper layers are offset relative that of lower ones to which they are connected. Parabola in the base of parabolic cylinder is described by the following equation: Y = (4·h_g·X²)/B_g , where X and Y are parabola abscissa and ordinate, h_g and B_g are correspondingly gabion width and height, here B_g = (2 - 4) h_g. In particular cases net may have different shapes of its cross-section, namely trapezoidal with expanded base, stepped with decreasing steps width in upward direction, T-shaped with shoulder oriented downwards and forming foundation or L-shaped.

EFFECT: increased load bearing capacity, reduced cost for foundation building.

5 cl, 10 dwg

Description

The invention relates to hydraulic engineering and can be used as a device for strengthening slopes, shore protection structures in eroded riverbeds, canals and other structures.

A device is known gabion [1], consisting of a metal mesh shell and aggregate in the form of active metallurgical, slag.

The disadvantages of this technical solution are:

- the rigidity of the gabion structure is insufficient, and the gabion net can be subjected to strong abrasion by sediment during operation;

- bearing capacity for bending and shear of such a structure is quite low;

- the design and method of construction is quite complicated;

- how such a technical solution is ineffective to use for fastening high slopes;

- in environmental terms, is not a favorable technical solution.

The closest technical solution is a gabion retaining wall [2], including layered gabions of nets and stones. The disadvantages of this technical solution are:

- the rigidity of the gabion structure is insufficient, since there is no connection between the layers inside the gabion and between the gabions;

- the shape of the gabion frame is variable;

- bearing capacity for bending and shear of such a structure is quite low;

- economically, it is not a favorable technical solution.

The purpose of the invention is to increase the bearing capacity when working on bending and shear and the economy of the structure.

This goal is achieved in that the gabion wall of a rectangular or other section consists of parabolic cylinders having a transverse or longitudinal orientation to the direction of flow. The gabion retaining wall of parabolic cylinders is constructed gradually, for this first the lower mesh is laid at the base. The mesh is stacked with offset and overlap. In the overlap place, the nets are interconnected by a connecting wire. The connecting wire is twisted by a device for twisting the wire, having for this two special holes into which the ends of the connecting wire are inserted and then twisted with a lever, thereby forming a strong connection. Parabolic cylindrical shapes are laid on the mesh carpet thus formed. The parabola lying at the base of the parabolic cylinder is described by the equation

Y = kX ² ;

where X, Y are respectively the abscissa and the ordinate of the parabola lying at the base of the parabolic cylinder; k is the coefficient.

и когдаWe find the value of the coefficient k, knowing that

and when

Y = h;

where B _g , h _g respectively the width and height of the gabions,

In _g = (2-4) h _g .

From here

или

or

We finally obtain the equation

The mold loading hole is filled with a layer of stones having a similar shape, after which it is removed. On the upper layer of stones having the shape of parabolic cylinders, the upper grid is laid by unwinding the rolls, which, hugging it, is attached using the connecting wire to the lower layer of the grid (figure 2).

Each individual parabolic cylinder on one linear meter of length has 6-10 fasteners of the connecting wire, the thickness of which is usually 4-5 mm, and the tensile strength can reach 800-1300 kg. Thus attached parabolic cylinders have increased stability against shear and bending construction loads.

Moreover, the orientation of the parabolic cylinders can be both transverse and longitudinal (Figs. 1, 4) with respect to the direction of movement of the water stream. The most favorable orientation with a purely gabion mount is transverse, since the formed parabolic cylinders with this orientation have increased structural rigidity for compression and bending, therefore they are less deformed during operation and are most stable when working under bending loads.

The most favorable gabion height is h _g = 0.2-0.5 m. At this gabion height, the width varies within V _g = 0.5-1.0 m and the stones under the mesh are maximally fixed due to the friction of the stones on the side surface of the mesh. The friction force on the side surface in this case exceeds the weight of the stones, and they will not fall out of the grid, even if gabions from parabolic cylinders are brought into a vertical position.

Next, along the layer of parabolic cylinders, a second layer of gabions of parabolic cylinders is laid, which is attached by a connecting wire to the ridges of the lower layer (Fig. 2). The ridges of the second layer of gabions are shifted relative to the ridges of the lower layer of gabions. The second is followed by the third, and so in succession a high retaining gabion wall is constructed, the height of which can reach large dimensions, while the wall can remain thin, since the structure is able to work on bending loads.

To improve the operation of the gabion retaining wall, the cross-sectional shape can be trapezoidal with an expanded base (figure 5). In this case, the pressure on the soil of the base decreases and the stability of the structure for tipping increases.

To enhance the bearing capacity when working on bending loads, as well as the stability of the structure to capsize, the wall can have a stepped cross-sectional shape with decreasing step width upward (Fig.6). The flat side of the wall adjoins the supported soil, thereby shifting the center of gravity of the retaining wall and increasing the moment that keeps it from tipping over.

The bearing capacity for bending loads and the stability of the gabion retaining wall is greatly enhanced if it has a T-shaped cross-sectional shape (Fig. 7) with a shelf oriented downward. The weight of the overlying soil presses on the shelf from the side of the supported soil, which enhances the stability of the structure by shear and tipping. This design significantly reduces the specific load on the soil base.

An economical and effective option when working on bending loads is the L-shaped cross section (Fig.9). This design can be effectively used as shore protection structures in eroded channels while protecting river banks or canals from erosion. The front part can be used as an apron. For this, the apron has a more elongated structure and can be lowered when washing away, without affecting the stability of the structure as a whole.

Figure 1 shows a cross section of a retaining gabion wall with a transverse orientation of parabolic cylinders to the direction of flow; figure 2 is a section aa, figure 1; figure 3 is a graph of a parabola; figure 4 is a cross section of a retaining gabion wall with a longitudinal orientation of parabolic cylinders to the direction of flow; figure 5 - retaining gabion wall with a trapezoidal cross-sectional shape; figure 6 - step gabion retaining wall; 7 is a retaining gabion wall with a T-shaped cross-sectional shape and a shelf oriented downward; Fig.8 is a section bb, Fig.7; figure 9 - L-shaped gabion retaining wall; figure 10 is a section CC, in figure 9.

The sloping mount 1 rests on a gabion wall of rectangular cross section 2, consisting of parabolic cylinders 3, having a transverse or longitudinal orientation to the direction of flow. The gabion retaining wall of the parabolic cylinders 3 is constructed gradually and the bottom mesh 4 is first laid at the base, and the stones 5 are covered on top with the upper mesh 6, which is fixed by the connecting wire 7 to the lower mesh 4. The gabion retaining wall can have a trapezoidal 8, step 9, T-shaped 10 or L-shaped 11 cross-sectional shape.

Gabion retaining wall is constructed and operates as follows. On the prepared base, the lower layer of mesh 4 is laid. The mesh 4 is stacked with offset and overlap. In the overlap place, the grids 4 are connected to each other by a connecting wire 7. On the thus formed carpet from the grid 4, shapes having the shape of parabolic cylinders are laid (Fig. 3). The parabola lying at the base of the parabolic cylinder (figure 3) is described by the equation

Y = kX ² ;

where X, Y are respectively the abscissa and the ordinate of the parabola lying at the base of the parabolic cylinder; k is the coefficient.

и когдаWe find the value of the coefficient k, knowing that

and when

Y = h;

where B _g , h _g respectively the width and height of the gabions,

B _g = (2-4) h _g . From here

или

or

We finally obtain the equation

The mold loading hole is filled with a layer of stones having a similar shape, after which it is removed. On the upper layer of stones 5, having the shape of parabolic cylinders, the upper grid 6 is laid out by unwinding the rolls, which, hugging it, is attached using the connecting wire 7 to the lower layer of the grid 4 (Fig. 2). Moreover, the orientation of the parabolic cylinders can be both transverse and longitudinal (Figs. 1, 4) with respect to the direction of movement of the water stream. The most favorable orientation is transverse, since the formed parabolic cylinders with this orientation have increased structural rigidity for compression and bending, therefore they are less deformed during operation and are most stable when working on bending loads.

The most favorable gabion height is h _g = 0.2-0.5 m. At this gabion height, the width varies within V _g = 0.5-1.0 m and the stones under the grid 6 are maximally fixed due to the friction of the stones on the side surface of the grid 6. Strength the friction on the side surface in this case exceeds the weight of the stones, and they will not fall out of the grid 6, even if the gabions from the parabolic cylinders are brought upright.

Next, along the layer of parabolic cylinders, a second layer of gabions of parabolic cylinders is laid, which is attached by a connecting wire 7 to the ridges of the lower layer (Fig. 2). The ridges of the second layer of gabions are shifted relative to the ridges of the lower layer of gabions. The second is followed by the third, and so a successively constructed high retaining gabion wall height, which can reach large sizes, and the wall at the same time, remain thin, since the design is able to work on bending loads.

To improve the operation of the gabion retaining wall, the cross-sectional shape can be trapezoidal 8 with an expanded base (figure 5). In this case, the pressure on the soil of the base decreases and the stability of the structure on tipping increases.

To increase the bearing capacity when working on bending loads, as well as the stability of the structure to capsize, the wall may have a stepwise cross-sectional shape 9 with decreasing width of the steps up (Fig.6).

The bearing capacity for bending loads and the stability of the gabion retaining wall is greatly enhanced if it has a T-shaped cross-sectional shape 10 (Fig. 7) with a shelf oriented downward. This design significantly reduces the specific load on the soil base.

An economical and effective option when working on bending loads is the L-shaped cross-section 11 (Fig.9). This design is effectively used as shore protection structures in eroded beds. The front part can be used as an apron.

The proposed gabion retaining wall is cheaper and more reliable in the work of known similar technical solutions. At the same time, the cost-effectiveness of these structures is 1.5-2 times greater, since the design is able to work on bending loads.

Sources of information

1. A.S. 1141143 USSR, MKI E 02 3/12. Gabion / Saratov I.E., Svirenko L.P. and Sherkov I.A. (USSR); application 09/14/83; publ. 02/23/85, Bull. No. 7 (analog).

2. Altunin S.T. Regulation of channels. State Publishing House of Agricultural Literature. Moscow, 1956, p. 63-64, Fig. 37-39 (prototype).

Claims (5)

1. Gabion retaining wall, including layered gabions of nets and stones, characterized in that the gabions are made in the form of parabolic cylinders oriented transversely or along the direction of flow and interconnected with offset gabion ridges of the upper layers relative to the gabion ridges of the lower layers, to by which they are attached, and the parabola lying at the base of the parabolic cylinder is described by the equation

where X, Y - respectively, the abscissa and ordinate of the parabola; B _g , h _g - respectively the width and height of the gabions, V _g = (2 ÷ 4) h _g . 2. The wall according to claim 1, characterized in that it has a trapezoidal cross-sectional shape with an expanded base. 3. The wall according to claim 1, characterized in that it has a stepped cross-sectional shape with decreasing width of the steps. 4. The wall according to claim 1, characterized in that it has a T-shaped cross-sectional shape with a shelf oriented downward, serving as the foundation. 5. The wall according to claim 1, characterized in that it has an L-shaped cross section.

Images