RU98200U1 - WATER DISPOSAL SYSTEM FOR PIPELINE CONSTRUCTION IN FROZEN AND WATERED SOILS - Google Patents

Abstract

The utility model relates to construction and is used when laying pipelines in thawing permafrost soils and in irrigated areas. The technical result of the claimed utility model is to simplify and accelerate the process of forming a drainage system while ensuring the stability of the pipeline and eliminating the flooding of the main trench. The drainage system during the construction of the pipeline in frozen and flooded soils, containing the main trench with the pipeline laid and covered in it, parallel drainage drainage systems, characterized in that an embankment of soil is made over the main pipe laying trench, and a water reduction system is made on both sides of it in the form of two small parallel trenches with the use of drainage polymer synthetic coatings (DPSP), which cover the embankment of the soil so that a directed drain to the vapor is formed from it shallow shallow trenches, or when the pipeline passes at an angle to the slope of more than 20 °, the drainage system is made on the basis of only one trench of the water reduction with the location down the slope parallel to the main one.

Description

The utility model relates to construction and is used when laying pipelines in thawing permafrost soils and in irrigated areas.

The prior art method of constructing a pipeline in flooded soils. Soft sheets are hung on the pipeline laid at the bottom of the trench, the edges of which are folded in advance in 2-3 layers and fixed in this state by mechanical tacks or surface fusion. Finished reinforcing mats from the bars are released into the trench with the spikes down, orienting the latter towards the closure of the wall and the bottom of the trench, on the folded edges of the soft panels. Partially loading the reinforcing mats from their own weight after the studs come in contact with the edges of the soft panels folded into the crease, they are pressed with the spikes, after which, while continuing to lower the opposite ends of the bars, the reinforcing mats are laid on the soft panels. The trench is filled with backfill soil until a surface roll is formed. The soil for filling the trenches is taken from the dump piled when digging the trench, moving it with a bulldozer. In the case of flooding the trench, the pipeline experiences a buoyancy force that causes some upward displacement of the pipeline. Together with the pipeline, sections of soft panels also rise, covering the pipeline from above. The sections of soft panels located under the reinforcing mats of the beams and fastened to them with the help of spikes are deprived of the ability to move. Therefore, the process of raising the pipeline under the action of the buoyancy of water is accompanied by the tension of the sections of soft panels hanging from the pipeline and the rotation of the reinforcing mats with the spikes turning out of the ground. Since the material of the panels has a relative elongation, there is a loss of the ballasting ability of the panels and it is possible to displace the pipeline from the design marks under the action of the buoyancy force of water (see SU 1809226 A1, 04/15/1993).

The prior art method for laying an underground trunk pipeline in an irrigated area (see SU 1013689 A, 04/23/1983). According to the known method, the trench is torn off with the formation of symmetrical trench broadening at calculated distances from each other, and then the berm (at the location of the broadening) is closed, the walls and the bottom of the trench with continuous flexible carpets placed on the pipeline, the width of which is no more than the broadening length in the direction of the axis of the trench. In conclusion, fill the trench and broadening with ballasting material, including open ground. To increase the reliability of pinching of the edge sections of continuous carpets, broadening is performed with the bottom having slopes away from the bottom of the trench. If it is necessary to place the technological road on the berm of the trench when performing its broadening in the form of extended trench-branches, the trench fragment with its symmetrical broadening and filling are carried out in two stages, at the first of which half the trench broadening is fragmented and filled on the lane of the technological road. In this case, backfilling is carried out after the passage, and before filling in each half of the broadening, the edge section of the rolled-up continuous carpet is placed. This allows you to further mount the pipeline directly on the berm of the trench, and then lower it into the trench.

Thus, as a result of the obtained possibility of crushing the edge sections of continuous carpets with soil, it was possible to fix the pipeline at the bottom of the trench. The disadvantage of this method is the lack of reliability of the soil being pinched by the backfill of the edges of the flexible carpets, especially when the backfill layer is low in height, since the latter is quite loose, unbreakable and its holding ability is ensured only by friction at the boundary of the "flexible carpet-ground" surfaces.

A known method of laying a pipeline, which is used in the construction of pipelines in flooded areas. The method is as follows. In the case of using flexible carpets with enhanced deforming properties, pits are made at the bottom of the broadening, while backfillings are filled with soil, flexible carpets fit to the bottom of the broadening and pits. If there is water in the trench, the bottom of the broadening is performed with a calculated slope towards the pipeline, while the thickenings are located above the water level. When constructing a pipeline in permafrost soils, the end sections of flexible carpets are placed outside the areola of thawing soil, i.e. they are constantly frozen into the ground. As a material for flexible carpets, fabric for ballasting gas pipelines TBG-360 can be used, as well as a container thread “Ponikon”. Thus, the preliminary stretching of flexible carpets makes it possible to more fully use their mechanical properties for ballasting the pipeline and eliminates the instability of loading forces due to the operational drawing of flexible carpets (see SU 1638419 A1, 03.30.1991).

The indicated solution has the abovementioned disadvantages - to increase the ballasting ability, it is necessary to increase the resistance to pulling the edges of flexible carpets out of the ground, which can be achieved by increasing the length of the edges of flexible carpets pinched by the soil, increasing the filling height, using compaction of the filling soil, increasing the drag force when pulling the end sections flexible carpets from soil backfilling trenches.

The closest known solution is the METHOD OF LAYING THE PIPELINE (OPTIONS) AND THE DEVICE FOR ITS IMPLEMENTATION (see RU 2244191, F16L 1/026, 10.01.2005). A trench is torn off with the formation of pairs of trench broadens symmetrical with respect to the pipeline that are located at a calculated distance from each other, and the pipeline is laid at the bottom of the trench. Transverse cross the pipeline and the bottom of the trench with flexible carpets at the locations of the broadening, pinch in the broadening the edge sections of the flexible carpets with backfilling of the trench. As anchoring elements, cylindrical textile containers filled with soil placed in the eyes of flexible carpets parallel to the pipeline are used as anchoring elements. Before the edge sections of the flexible carpets are pinched, each of them is tensioned to fix the tension, and the preliminary provisional stretching of the edge sections is carried out when filling the broadening and trench with soil, ensuring that the flexible carpets fit to the bottom of the broadening and trench, while filling the ground with each pair of broadening and trench leading to the pipeline and symmetrically with respect to it. Increases the reliability of fixing the pipeline at design elevations.

This method is technically complicated and costly. The method uses a closed drainage system and drainage pipes. A mound of soil over the trench and slopes have to be formed from additionally dug soil.

Also the closest solution is the METHOD FOR PIPELINE STRUCTURE IN PERMANENTLY FROZEN SOILS (OPTIONS) (see RU 2244192, F16L 1/026, 01/10/2005).

On sections of the route with a quiet relief, on sections of the route cut by a hydrographic network and with slopes of no more than 30%, a trench is torn in the active layer with a depth that ensures that the upper generatrix of the pipeline is not higher than the level of the day surface. Before laying the pipeline, the bottom, walls and berms of the trench are lined with panels of non-woven synthetic material (HCM). Backfill soil is placed in ballasting polymer-panel devices (PPU) hung on the pipeline or in containers of polymer-container ballasting devices (PCBU). In the sections of the route with slopes, anti-erosion partitions are created in the trench from the NSM panels by the formation of a funnel, the neck of which is located down the watercourse, covers the pipeline and is fixed on it with the estimated value of the gap between the neck and the pipeline. The funnel is formed by overlapping the natural slope of the backfill soil with the free lower edge of the NSM panel with the placement of PPU or PKBU on the lower part of the funnel and with the subsequent filling of the embankment protecting the pipeline. On the sections of the route cut by the hydrographic network at the crossings with opposite slopes of the microrelief, erosion barriers from erosion towels are created in the trench, and the backfill soil is placed in tanks suspended on the pipeline of soil-filled weighting agents (GU) from technical fabrics. In low places at the intersection of oncoming slopes in a trench, a culvert or culvert is constructed. It increases the reliability of pipeline ballasting at a high level of groundwater and with a weak bearing capacity of the upper soil layer, reduces the amount of excavation work associated with the development of trenches in frozen soils, ensures the stability of the pipeline in a horizontal plane, especially at bends of the route, and reduces the volume of the embankment.

This method is also technically complex and costly. The method uses a closed drainage system and drainage pipes. A mound of soil over the trench and slopes have to be formed from additionally dug soil.

The technical result of the claimed utility model is to simplify and accelerate the process of forming a drainage system while ensuring the stability of the pipeline and eliminating the flooding of the main trench.

The utility model is illustrated by drawings, where Fig. 1 shows a diagram of a pipeline construction in frozen and flooded soils on a track without a slope, where 1 is a pipeline trench, 2 is a pipeline, 3 is a water reduction system (shallow trenches), 4 is a plastic drainage synthetic coating, 5 - pegs - fixing the drainage coating to the ground. And Fig. 2 shows a diagram of the construction of a pipeline in frozen and flooded soils on a track with a slope.

The claimed technical result is achieved due to the fact that the drainage system during the construction of the pipeline in frozen and flooded soils, containing the main trench with the pipeline laid and filled in it, parallel drainage drainage systems, characterized in that over the main trench (1) of laying the pipeline (2 ) a mound of soil was made, and on both sides of it (see Figure 1) a water reduction system was made in the form of two small parallel trenches (3) using drainage polymer synthetic coatings (DPSP) (4), they covered the embankment so that a directed drain is formed from it to parallel shallow trenches (3), or when the pipeline passes at an angle to the slope of more than 20 ° (see Figure 2), the drainage system is based on only one trench (3) with the location down the slope parallel to the main (1).

The water reduction trenches (3) are preferably made in the zone of seasonally thawed soil with a depth of 0.4 ÷ 0.7 m, width up to 1 m and at a distance from the pipeline axis 7 ÷ 10 m. Drainage polymer synthetic coatings (4) are laid on the soil surface with slope from the axis of the pipeline towards small trenches 3 ÷ 10 °, and the bottom of these trenches is covered with DPSP, while the design of DPSP allows you to organize a directed drain. The edges of the DPSP coming out of small trenches and DPSP at the bottom of these trenches can be fixed, for example, with pegs (5) made of polymeric materials, in the soil with a step along the pipeline 5 ÷ 6 m. ÷ 1.5 m.

In order to ensure the stability of the pipeline and eliminate the watering of the main trench (pipeline route), including on sloping, irrigated areas, a water reduction system is created by installing two small parallel trenches using drainage polymer synthetic materials (DPS), which cover the embankment of the backfill formed over main trench where the pipeline is laid.

Simplification and acceleration of the process of formation of the drainage system is provided due to the fact that to create a slope from the embankment above the main trench, soil excavated from auxiliary shallow trenches can be used. In addition, the use of drainage pipes is not required, which also reduces the cost of the formation of drainage in comparison with prototypes and the drainage system is formed half-open.

Claims (5)

1. The drainage system during the construction of the pipeline in frozen and flooded soils, containing the main trench with the pipeline laid and filled in, parallel drainage drainage systems, characterized in that an embankment of soil is made over the main trench of laying the pipeline, and a system is made on both sides of it water reduction in the form of two small parallel trenches with the use of drainage polymer synthetic coatings (DPSP), which cover the embankment of the soil so that a directed drain to the allelic shallow trenches, or the passage duct to slope at an angle of more than 20 ° drainage system is made based on only one dewatering trench with the location down the slope parallel to the main. 2. The drainage system according to claim 1, characterized in that the troughs of the water drainage are made in the zone of seasonally thawed soil with a depth of 0.4 ÷ 0.7 m, a width of 1 m and a distance from the axis of the pipeline 7 ÷ 10 m 3. The drainage system according to claims 1 and 2, characterized in that the drainage polymer synthetic coatings (DPS) are laid on the surface of the soil with a slope from the axis of the pipeline towards small trenches of 3 ÷ 10 °, and the bottom of these trenches is covered with DPS, DPSP allows you to organize a directed drain. 4. The drainage system according to claim 3, characterized in that the edges of the DPSP coming out of small trenches and the DPSP at the bottom of these trenches are fixed in the ground with a step along the pipeline of 5–6 m. 5. The drainage system according to claim 2, characterized in that the inlet and outlet of the trenches are equipped with special trays from DPSP with a length of 1 ÷ 1.5 m.