SU1155661A1 - Method of constructing a canal - Google Patents

Abstract

1. METHOD OF CONSTRUCTION OF A CHANNEL, mainly in permeable soils, including the development of its dredge with a cross-section equal to the designed size, with the formation of slopes, which are characterized by the fact that, in order to increase the quality and intensity of work by forming stable slopes and reducing construction time, the development of the soil to the design mark two channels carry out additional development of the soil below the specified mark. With simultaneous trimming of slopes, along the length of the developed channel, arrange temporary transmigration is made, the channel of the channel between them is filled with water and the filling is filled to saturate the ground with water within the width of the zone of collapse, after which the slopes are formed by the collapse of the soil due to the discharge of water.

Description

2. A method according to claim 1, characterized in that the water is discharged by disassembling and self-washing out the transition between the filled water

and ready-made sections of the channel, whereby to build up the soil of the jumper below it, lowering the bottom of the channel is previously carried out.

3. The method according to claim 1, which is based on the fact that the undercut of the channel channel slopes are cut at a depth that ensures the equality of the volumes of the soil.

55661

and deeper channel and defined by the formula

"2h depth of undercut from bottom

de

channel, m,

i width at the bottom of the submerged bed. Mi coefficient of mortality

 fl slopes of the submerged bed;

P is the cross-sectional area of the break-down slope, m.

 one .. , .

The invention relates to the technology of production of works by means of hydromechanization in the construction of canals, collectors and other pro-profile grooves of great length in permeable soils.

There is a method of developing an underwater profile recess, in which at least two pioneer trenches are torn off in the upper channel of the channel, the outermost of which are located along the contour and are made with profile external slopes O

The disadvantage of this method is to obtain a design slope only in the upper floor of the excavation, as well as the difficulty in organizing the construction due to the use of different types of earth-moving machinery.

The closest to the proposed technical solution is a method for constructing a canal, mainly in permeable soils, including the development of its dredge with a cross-section of equal size to the design, with the formation of slopes C2l.

According to this method, the slopes are more steep than the design ones, and the bottom of the excavation is wider, according to the principle of maintaining an equal volume. In the future, there is a gradual self-cooling of the slopes to the angle of natural slope.

The disadvantage of this method is the duration of the self-curing process and the impossibility of controlling the process of forming design slopes due to the influence of various factors (wave action, strength of filtration pressure, etc.).

The purpose of the invention is to improve the quality and intensity of work by shaping steady slopes and reducing construction time.

The goal is achieved according to the method of construction of the canal, including the development of its dredger with a cross section of equal design, with the formation of slopes, after the development of the soil to the design level of the bottom of the canal, additional development of the soil below the specified mark with simultaneous cutting of the slopes is carried out Temporary cross bridges are arranged in the developed channel, the channel of the channel between them is filled with water and the filling is filled to the maximum of the soil within the width The zones of collapse, after which the slopes are formed by the collapse of the soil due to the discharge of water.

Intensive discharge of water is carried out by disassembling and self-erasing the bridge between the water-filled and finished sections of the channel, while to build up the soil of the bridge below it, the bottom of the channel is reduced beforehand.

In addition, the channel slopes are cut under a depth that ensures equal volumes of the soil of the collapsed slopes and depth of the channel and is determined by the formula

In with 2w

Vi undercut depth from bottom

where is the channel, m-,

B width at the bottom of the submerged bed, m; mortgage rate

hn slopes of the submerged bed;

F is the cross-sectional area of the break-down slope, m.

The essence of the method lies in the artificially induced collapse of the slopes of the channel, which is arranged with over-penetration and a cross-section equal to the project size.

In this case, the trajectory of the breakable steady slope is determined by the equation

four. -,

x - jz cent-cen () j, (1)

X, Z - coordinates of the trajectory of a stable slope, m-, the specific gravity of the soil,

G / angle of internal friction, hail total grip, t / m.

By knowing the trajectory of a stable slope, it is possible to determine the area of the transverse canopy of the collapsed slope using the formula

(x, -mzj2 /

(2)

g ;;; I

where x, z are the coordinates of the point of intersection of the collapsing slope with a temporary slope of the channel channel, m; m - the coefficient of laying

temporal slope of the submerged bed. The area of the submerged channel is determined by the formula

P, b (), (3)

where h (is the depth of decompression, m;

four

  height of the retrained bed, MV b - width along the bottom of the recessed bed, m, equal conditions depth of undercut from the bottom of the channel

B- b

Zm

The time it takes for us to e-. nor the ground water of the zone of collapse, is determined from the equation of water infiltration from open channels

/ f u)

(one

-t time of water saturation of grundde, day,). n - soil porosity-,

k is the filtration coefficient,

m / day;

X - coordinates of the collapse trajectory from (1) i tl - the argument to be determined

depending on soil characteristics, avg average filling depth

channel m

0 The collapse of the soil is achieved by a longitudinal undercut of the slope of the channel along the boundary of the collapse, the water saturation of the soil of a given zone of the collapse of the slope and the intensive discharge of water in this section.

The stability factor of the temporary slopes of the channel is equal to

, v,

(AND

ian.

C, - holding forces, KHJ 1 - shearing forces, kN. When the slope is flooded, the holding forces increase due to the static pressure of water on the slope, and the shearing forces are reduced due to the replacement of the weight of the soil mass P by the weight of the soil suspended in water (

up

. I.

(7)

Well

gap

With an intensive discharge of water, the holding forces decrease due to filtration pressure and soil moisture, and the shearing forces increase due to filtration pressure. In this case, the factor of stability becomes minimal and is equal to R ". At the same time, conditions are created for the collapse of the soil with the creation of stable slopes with a maximum decrease in the water level. FIG. 1 shows the construction scheme of the canal dredger house in plan in FIG. 2 is a section A-A in FIG. one; in fig. 3 is a section B-B in FIG. 1. Example The method was carried out as follows (construction of the experimental section of the No.ar collector in the Mary region of the Turkmen SSR. Previously, the route 1 of the channel 1 laid a pioneer trench 2 through which water was supplied. The dredge 3 developed the channel 4 of the channel 1 with the following parameters: 20 m, 11 11 m, t O, 5. At a depth of 8 m, details of the longitudinal undercut 5 of the temporary slope 6 with the help of the jetting nozzle of the dredge 3. Section 7 of the slot 4 blocked the upper -8 and lower 9 with bridges with a distance between them. 400 m Section 7 is filled with l 11 6 One to the maximum level of 10 with the help of a floating pump station 11. Experimental data showed that after 5 days the slope of sandy loam was saturated by water infiltration from slot 4, the water saturation zone was 8 m from the canal's edge. 9 and self-flushing it dumped water into the finished section 12 of channel 1. At the same time, the bulkhead soil was placed in a previously designed recess 13. Due to the rapid discharge of water, there was a violation of the stability of water-saturated slopes 6 and landslide 14 s primer of 66 m to 1 running. The channel into the recess 15 of slot 4 with the formation of the design sustainable section 16 of channel 1. Thus, during the construction of the channel by the proposed method, a steady channel profile of the channel without special land works on the formation of slopes is formed due to the artificial caused break of slopes. As a result of applying the proposed method, the quality and intensity of the work performed is improved.

Claims (4)

1. METHOD OF CONSTRUCTION of construction periods, after excavation to the design elevation, two channels carry out additional excavation below the indicated elevation, while cutting the slopes, along the length of the developed channel, temporary cross lintels are arranged, the channel of the canal between them is filled with water and maintained to fill until saturated soil water within the width of the caving zone, after which slopes are formed by caving in the soil CHANNEL, mainly in water Figure 1 2. The method according to π. 1, characterized in that the discharge of water is carried out by disassembling and self-washing the jumper between the filled water and the finished sections of the channel, while to deposit the soil of the jumper below it, the bottom of the channel is preliminarily lowered. 3. The method according to claim 1, wherein the undercut of the slopes of the channel of the channel is carried out at a depth that ensures the equality of soil volumes of collapsed slopes and overdeeping of the channel and is determined by the formula 4 _-V b ² - 8ptR '2 ™' where l is the depth of the cut from the bottom of the channel, m; B - width along the bottom of the recessed channel, m; • tn is the coefficient of laying of the slopes of the deepened channel; P is the cross-sectional area of the collapsed slope, m ² .