RU2324028C2 - Open-ended transversal bank protection structure - Google Patents

Abstract

FIELD: hydraulic and agricultural engineering construction.

SUBSTANCE: structure comprises spacer assemblies consisting of a plastic pipe with spacers and reinforcements inside. Said spacers are arranged in triangles by means of fastening them with ties around transversal reinforcements to form an assembly. The cross-section area of the structure represents triangular trusses made of the spacer assemblies, and their height Н_i gradually increases by the end of the structure up to a value equal or exceeding Н = h + h_р, and is described by the following equation: Н_i = h + h_p/L_w ² · х², where Н_i is the height of the triangular truss disposed at a distance х from the root of the structure; h - height of the triangular truss disposed at the root of the structure; h_р - depth of washout at the head of the structure; L_w - length of the open-ended transversal bank protection structure; х - distance from the origin of coordinates.

EFFECT: reduction of costs for building the bank protection structure; increasing its service life; the most environmentally favourable solution of the problem of protection of river banks against washout.

5 dwg

Description

The invention relates to hydraulic engineering and land reclamation construction and can be used as shore protection structures in eroded riverbeds, canals, slopes of dams, designed for various purposes, and other structures.

A device for attaching a slope of an earth structure [1] is known, comprising a synthetic filter coating laid on the slopes, retaining elements and a layer of stone outline. The holding elements are made in the form of crossbars, racks with hinges, ropes, mesh and limiters. The stone sketch is made in the form of gravel. The lower ends of the uprights are pivotally attached to the crossbar, and their upper ends to the rope. A mesh is attached to the rope. One of the ends of the rope is attached to the crossbar, and their other free ends are stretched due to the application of force, and the posts and the crossbar are connected by K-stops. Between the coating and the mesh, a layer of stone is laid. A layer of gravel protects the coating from dynamic wave action. In turn, it is reliably protected by a mesh held in place by ropes. The disadvantage of this technical solution is that:

- the mount is in direct contact with the fluid flow and entrained sediments and therefore can undergo rapid attrition and destruction in a short time;

- the design is a rather complicated technical solution, which makes it not reliable in operation and expensive in cost;

- the efficiency of fastening is significantly reduced when there are large fluctuations in the water level, fluctuations in speed and flow rate in the river or canal.

The closest technical solution is a transverse through-shore protection structure containing elements assembled in a triangular prism [2]. The disadvantages of this technical solution are:

- the inconvenience of connecting nodes using complex technical solutions for connecting reinforced concrete elements;

- fastening in economic terms is not always an effective technical solution due to the use of industrial reinforced concrete structures.

The purpose of the invention is to increase the efficiency and reliability of protecting the banks of riverbeds from erosion and durability of the life of the shore protection structure.

This goal is achieved by the fact that on the eroded shore, a through transverse (Fig. 1) shore protection structure is installed. In this case, the installation angle depends on the width of the channel, the possible dump of the stream to the shore, and other morphological elements of the stream and channel. The most favorable option is to install them across the direction of the flow of one plane onto the bottom of the river, which creates the most favorable conditions when flowing around. The length of the transverse transverse shore protection structures and the distances between them are determined by the developed methodological recommendations. The transverse transverse shore protection structure (Fig. 2) is assembled mechanically by attaching spacers to the reinforcement with connecting clamps that form triangular trusses. So sequentially connecting the spacer elements to the reinforcement, the height of the through transverse shore protection structure can be increased to any size. The stream, partially flowing through the through transverse shore protection structure, washes the head part and therefore its deposition occurs. To prevent this phenomenon, the size of the triangular truss of the head part is increased and is equal to H = h + h _p , where h is the height of the triangular truss at the beginning of the through transverse shore protection structure; h _p - erosion depth at the end of the through transverse shore protection structure.

The erosion depth in the head of the through transverse shore protection structure depends on the building coefficient and is determined by the formula

where k _t is a coefficient depending on the type of soil for sand fineness, d _cf = 14 mm, k _t = 50; ν is the average household speed.

Building coefficient can be determined by the formula

where N is the number of triangular farms in the considered section of the through transverse shore-protecting spur; n is the number of rods in a triangular truss; b is the width of the spacer element; k is the coefficient of uneven distribution of the spacer elements in the structure, which can be taken equal to 0.5; _W L - length of the through cross-bank protection structures.

. Разделив это уравнение и проинтегрировав, получим

. Подставляя начальные и конечные условия, получим значение коэффициента

. Тогда

To achieve the greatest effect, the height of the triangular trusses increases gradually from the root to the head of the through transverse shore protection structure and, therefore, the condition

. Separating this equation and integrating, we obtain

. Substituting the initial and final conditions, we obtain the value of the coefficient

. Then

где H_i - высота треугольной фермы на расстоянии x от начала координат.The height of the triangular trusses increases gradually to a value equal to or greater than H, and is described by the equation

where H _i is the height of the triangular truss at a distance x from the origin.

As a result of a decrease in the flow velocity, sediment sedimentation to the bottom occurs and lateral water erosion of river banks ceases.

The spacer element consists of a plastic pipe, in which there is a filler and fittings. As a filler, high-strength concrete M 250 ÷ 300 can be used.

The flow of water flowing through a through transverse shore protection structure reduces its speed, resulting in a decrease in the transporting ability of the flow and the precipitation of suspended sediment along the coast.

Figure 1 shows a longitudinal section through a transverse shore protection structure; figure 2 is a triangular cross section of a precast through the transverse shore protection structure, section 1-1 in figure 1; figure 3 is a triangular cross section of a precast through the transverse shore protection structure, section 2-2 in figure 1; figure 4 - curve of the height of the triangular trusses along the length of the through transverse shore protection structure; figure 5 - connecting node spacer element to the valve.

On the eroded shore 1, a through transverse shore protection structure 2 is installed, consisting of triangular trusses 3 assembled from spacer elements. The spacer element consists of a plastic pipe 4, in which the reinforcement 5 and the aggregate 6 are located. The spacer elements are mechanically attached to the reinforcement 7 using clamps 8.

A transverse transverse shore protection structure is constructed and operates as follows. On the eroded shore 1, a through transverse (Fig. 1) shore protection structure 2 is installed. The installation angle depends on the width of the channel, the possible dump of the stream to the shore, and other morphological elements of the stream and channel. The length of the transverse transverse shore protection structures 2 and the distances between them are determined by the developed methodological recommendations. The transverse transverse shore protection structure 2 (FIG. 2) is assembled mechanically by attaching spacers (FIGS. 2, 3) to the reinforcement 7 with connecting clamps 8, which form triangular trusses 3 (FIG. 2). The spacer element consists of a plastic pipe 4, in which the reinforcement 5 and the aggregate 6 are located. Thus, by connecting the spacer elements to the reinforcement 7 in series, the height of the through transverse shore protection structure 2 can be increased to any size. Moreover, the cross section of this structure is a triangular truss 3.

The stream, partially flowing through the through transverse shore-protecting structure 2, undermines the head part and therefore its deposition occurs. To prevent this phenomenon, the size of the triangular truss 3 of the head part is increased and is equal to H = h + h _p , where h is the height of the triangular truss at the beginning of the through transverse shore protection structure; h _p - erosion depth at the end of the through transverse shore protection structure.

. Разделив это уравнение и проинтегрировав, окончательно получим, что высота треугольных ферм 3 увеличивается постепенно до величины, равной или превышающей Н, и описывается уравнением

, где H_i - высота треугольной фермы на расстоянии х от начала координат.To achieve the greatest effect, the height of the triangular trusses 3 increases gradually from the root part to the head of the through transverse shore protection structure 2 and, therefore, the condition

. Dividing this equation and integrating, we finally obtain that the height of the triangular trusses 3 increases gradually to a value equal to or greater than H, and is described by the equation

where H _i is the height of the triangular truss at a distance x from the origin.

The flow of water flowing through the through transverse shore protection structure 2, reduces its speed, resulting in a decrease in the transporting ability of the stream and the loss of suspended sediment along the coast. To increase the efficiency of the through transverse shore protection structure 2, the frequency of installation of triangular trusses 3, or the building coefficient, increases from the end to the head.

Flexibility is a huge advantage of this structure, since it is in the water and it is impossible to avoid deformations of the bottom and base, and this will entail deformation of the structure, which is not dangerous for this type of coastal protection.

The proposed technical solution has several advantages over other previously known, the main of which is the speed of assembly.

The proposed technical solution is cheaper than known, while the durability of these structures is greater than previously known similar technical solutions.

In environmental terms, this is the most favorable solution to the problem of protecting coasts from erosion.

Information sources

1. A.c. 1461821 USSR, MKI E02D 17/20. A device for fastening the slope of an earth structure / Shkundin B.M. and Novozhilov A.P. (THE USSR); Application 03/04/87; publ. 02/28/89, Bull. No. 8 (analog).

2. RF patent No. 2279506 Е02В 3/12, Prefabricated transverse shore protection structure / Lamerdonov Z.G .; Application 12/14/2004; publ. 07/10/2006, Bull. No. 19. - 6 p. (prototype).

Claims (1)

A transverse cross-shore protection structure containing prefabricated spacer elements, consisting of a protective coating in which aggregate and reinforcement are located, and assembled into triangles by fixing spacer elements around transverse reinforcement with the formation of nodes, while the cross-section of the structure is a triangular truss, height H _i which from the root part to the head of the structure increases gradually, characterized in that the protective coating is made in the form of a plastic pipe, spacer elements Options attached around the transverse reinforcement by clips, and the height of the triangular trusses increases to a value equal to or greater than H = h + h _p, and is described by the equation

Where H - the height of the triangular truss in the head of the structure; h is the height of the triangular truss in the root of the structure; h _p - erosion depth in the head of the structure; H _i - the height of the triangular truss at a distance x from the root of the structure; L _W - the length of the through transverse shore protection structure; x is the distance from the origin.

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