Working design of VL 220kV

Contents

TABLE OF CONTENTS

1 Introduction

2 Study of engineering and geological conditions

3 Physical and geographical characteristics

4 Geological structure

5 Freezing ground conditions

6 Physical and mechanical properties of soils

7 Conclusions and recommendations

8 List of normative, printed and archival documents used for report development

Applications

And

Certificate of admission to work on engineering surveys in the Russian Federation issued by NP SRO "AIIS" 23B

Technical Assignment for Performance of Engineering and Geological Surveys .27V

Table of results of measurement of specific electrical resistance of soils along the route VL 220 kV "Gorodskaya-Peledui.." 28D

Temperature table of permafrost soils at a depth of 10.0 m.. 33D

Catalogue of coordinates and heights of mine workings... 34E

Partial values of soil composition, condition and physical and mechanical properties

Calculation Content

P

Content to calculation

F1 foundation calculation.....

F4 foundation calculation.....

F14 foundation calculation.......

Calculation of F15 foundation.......

F17 foundation calculation.....

F19 foundation calculation.....

F20 foundation calculation..

F22 foundation calculation......

Calculation of F23 foundation..

Calculation of piles...

Process loads on foundations.....

Calculates the displacement and rotation angle of the pile at the bottom of the pile.

2 study of engineering and geological conditions

In 1972, the Novosibirsk Institute "Energetproekt" conducted engineering and geological surveys from the city of Mirny to the village of Peledu to develop a project for the construction of VL110 kV. The materials of these surveys have not been preserved.

In 2008, a working project for the construction of VL110 kV VitimPeledu was released with the 110 kV Vitim substation of OJSC by the Irkutsk branch of the Vostibenergosetproekt Institute of the Siberian ENTC, where volume V highlights comprehensive surveys at PS110 kV Peledu, and the entire work complex is reflected in volume VI. The materials of the latest geotechnical surveys have been analyzed and used in the preparation of this report for comparisons.

In 2007, the hydrogeological party of the State Unitary Mining and Geological Enterprise of the Republic of Sakha (Yakutia) Yakutgeologia searched for groundwater for household and drinking purposes in the Lensky ulus. The results of these works are reflected in the report and were used to correct individual sections.

In 2009, a project was drawn up "Prospecting for groundwater for water supply to the village of Peledu" Lensky district in 20092010. "

The individual chapters of this project are partly used in this report.

In addition, in writing the report, regional research materials related to engineering geology, geocryology and geomorphology were involved and used for review and comparisons.

This report is based on the materials of engineering and geological surveys carried out by the engineering geology department of DneprVNIPIenergoprom OJSC and Stroyizyskiya LLC in 2010.

Physical and geographical characteristics

Designed VL220 kV City Peledui is located in the southwestern part of the Republic of Sakha (Yakutia) on the territory of the Lensky ulus and runs from the Gorodskaya PS in Lensk to the Peledui PS, 217 km long.

The city of Lensk, the administrative, industrial and cultural center of Yakutia, covers an area of ​ ​ more than 20 km2. Confined to the middle stream of the river. Lena, located on its left bank and located within the large geomorphological structures of the Central Siberian plateau and the Yakut plain.

Lensk is a large river port through which all the necessary diamond mining industry in Mirnogo is supplied. There is a functioning airport in Lensk. Lensk is connected with Mirny by a constantly operated road, and with Yakutsk by a 1,600 km autosimnik, which operates from December to April.

Geomorphologically, the VL220 kV route is located within the Prilensky structural-denudation plateau and is a hilly row surface with absolute elevations along the wells of 193.84 m (squ.542) - 561.89 m (squ.221) in the Baltic altitude system and a total slope to the northwest.

According to the predominance of relief-forming exogenous factors, two types of relief are distinguished: errosine denudation and errosion accumulative.

The first was formed in the process of neotectonic elevations of territories. Its surface appearance depends on the type of geological structure and lithological composition of rocks.

Here differ: the gryadovouvalisty plateau within development of the deployed deposits of the Cambrian to Entre Rios river of the river LenyPeleduy; a wavy hollow-walled plateau on linear folded Cambrian carbonate-clinged rocks; hollow-hilly plateau on terrigenous sediments of jura.

The second type of relief is errosion-accumulating, confined to the slopes of the river valleys of Lena and Peleduya, as well as the Boruok River, belonging to the basin of the Nyuya River. Watersheds are flat or rounded. The slopes in the upper part are gentle, rarely medium steeply.

Geocryologically, the area is part of the island distribution zone of permafrost rocks. In river valleys, MMP capacity reaches 70 m. On slopes and watersheds, it occupies up to 50% of the territory with MMP capacity - 25.030.0 m.

The power of the zone of seasonal freezing and seasonal pouring varies from ~ 2.5 m to 4.5 m. Of the cryogenic forms, seasonal buoyancy tubers are most common, sometimes thermocarst manifestations are found.

The hydroset of the region is represented by the Lena and Peledu rivers with their numerous tributaries. Tributary valleys are narrow, sometimes compressed by steep slopes with rock outcrops. The upper reaches of the valleys are wide, often with swampy floodplains. The main feed of the watercourse is obtained due to atmospheric precipitation, to a lesser extent due to groundwater.

The beginning of the water supply is mid-October, spring ice drift is mid-May. The thickness of the ice on large rivers reaches 180 cm, the opening of large rivers, as a rule, is violent. During opening, the water rise is 3-6 m and is accompanied by destruction of the banks. The rivers are most full in late May - June. The lakes are small, distributed mainly in the valley of the Peledu River, freeze and open simultaneously with the rivers.

Seismicity of the territory, according to the seismic zoning maps of the Republic of Sakha (Yakutia) - 6 points.

The climate of the region is sharply continental, characterized by cold long winters (October - the first half of April) and relatively short summers (June - August).

The spring season is small (the second half of April is May). Due to increased cyclone circulation in the spring, an unstable type of weather prevails.

Absolute minimum air temperature - minus 61 ° С, maximum - plus 35 ° С is given in operation.

The annual rainfall varies from 358 mm to 575 mm. In summer, northern winds prevail. In winter, the wind speed is 0.93.8 m/s, but in combination with severe frosts, with a relative humidity of 7280%, very harsh conditions are created.

In the summer, the wind speed is greater and can reach hurricane strength - up to 17 m/s.

Snow cover is formed in the first half of October and remains within 220 - 250 days, its height by the end of winter reaches 60 - 90 cm. During this period processes of freezing of soil of an active layer, pucheniye, vypuchivaniye and frosty cracking begin.

Climatic parameters of the main weather elements required for calculations are adopted according to SNiP for the city of Lensk.

Cold period of the year

Air temperature of the coldest days, availability:

0.98 - minus 55 ° С;

0.92 - minus 53 ° С.

Air temperature of the coldest five days, availability:

0.98 - minus 52 ° С;

0.92 - minus 49 ° С.

Absolute minimum temperature -57 ° С

Duration of period with average daily air temperature:

[0 ° C - 208 days at an average temperature of minus 18.8 ° C;

[8 ° С - 259 days at average temperature minus 14.2 ° С;

The average monthly relative humidity of the coldest month is 75%.

The rainfall for November-March is 103 mm.

The prevailing wind direction for December-February is western.

Climatic parameters of the warm season:

- barometric pressure - 980 hPa;

- average maximum air temperature of the warmest month + 24.7 ° С;

- absolute maximum + 36 ° С;

- average monthly relative humidity of the warmest month - 68%;

- rainfall for April - October - 283 mm;

- daily maximum precipitation - 106 mm;

- the prevailing wind direction for June - August - Western.

The average annual air temperature is 6.2 ° C.

According to the zoning according to climatic characteristics, the location area of ​ ​ the designed route VL220 kV belongs to the fourth snowy area with a standard weight value of 2.4 kPa (240kgf/m2), the thickness of the ice wall - to the second area - 5 mm and the wind pressure - to the first area, with a value of 0.23 kPa (23kgf/m2).

Geological structure

Structurally, the survey territory is located within the Siberian platform bordering the Aldan crystal shield.

The tectonic structure of the area of ​ ​ the designed VL220 kV is relatively complex. Here, folded structures are often complicated by ruptured violations of the northeast plan.

All disjunctive disorders are grouped into two tectonic zones: Karamsk and VerkhneAlysardakh.

The first, the largest, gravitates to the Karam River basin and stretches on the right bank of the Peledu River. It is a series of discharges of northeastern extension from 8 to 12 km long.

In the most fragmented areas (the lower reaches of the Kurtah and Karam rivers), salt and hydrogen sulfide springs were recorded.

The Verkhne-Alysardakh zone within the southeastern part of the region is characterized by discharges of northeastern and northwestern extension. At the crossing areas of the discharges, narrow grabens (lower reaches of the Peledu River) are noted, made by deposits of the middle-upper Cambrian.

Paleozoic formations of the Cambrian and Ordovician periods take part in the geological structure of the region and adjacent territories, everywhere covered by Cenozoic sediments represented by the lower, middle and upper Quaternary formations of the elluvial deluvial, alluvial-deluvial and alluvial genesis.

The lithologic-stratigraphic section studied along the route VL220 kV to a depth of 10.0 m is presented in the following form from top to bottom:

- soil-plant layer (e IV) - light-carbonaceous, gray, brownish, frozen, in a thin state of semi-solid and refractory consistency, distributed everywhere with a thickness of 0.1-0.2 m;

- loam with an admixture of organic substances (ed IIIIV) - brown, yellowish, frozen, weakly solid, when thawing semi-solid, has a limited distribution, mainly on sections of the route with the valleys of streams and depressions of the relief, with a capacity of 0.6 m to 0.8 m (squ.3a, 40a, 524a).

- mixture with an admixture of organic substances (ed IIIIV) - brown, frosty, weakly moist, in a thin state less often plastic consistency, is widespread, on many sections of the route lies under the soil layer with a capacity of 0.3 m - 1.3 m (Skv. No. 110, 58, 88) to 8.3 m - 9.8 m (Skv. No. 151, 153, 152);

- loam with an admixture of wood and crushed stone (ed III) - brownish, light gray, often with a reddish tint, melted and frozen, solid and semi-solid in the waist state, has a wide distribution, lies under the soil-plant layer or under sandy sand with an admixture of organic matter from 0.3-0.8 m (section No. 68, 69, 387, 388, 413, 424) up to 7.9-8.8 m (section No. 386-389);

- soup with an admixture of drizzle and crushed stone (ed III) - reddish-brown, brown, brownish-yellow, frozen and melted, weakly moist, mostly solid, rarely plastic, distributed on large sections of the route, lies more often on rocky and semi-rocky soils with a capacity of 0.2 m - 0.4 m (74,9 to 9,9) 0,9, 5,8 m.

- dust sand (ad III) - gray, yellowseed, brown, frosty and melted, weakly mild sometimes contains lenses of medium-sized sand and individual pebble and gravel particles, in some wells it occurs in the form of lenses with a capacity of up to 2.0 m (fr. 361), distributed to a greater extent in the initial sections of the VL route (squ.55-78) and at the penultimate (squ.361-375) with a power of 2 m to 9.8 m (squid. 55 and 57);

- fine sand (ad III) - grayish-yellow, brownish-yellow, gray, frozen and melted, weakly solid of medium density and dense, distributed locally with a capacity of 1.5 m (squ.62) to 3.0-6.0 m (squ.368-369), and the maximum opened capacity of 8.0 m is noted in well No. 366;

- medium-sized sand (ad IIIII) - gray, yellowtoser, frozen in the zone of seasonal freezing, weakly arid, medium density, in a thin state - wet, distributed at the beginning of the VL route (wells No. 3a, 5-8) opened with a capacity of up to 8.5 m and at the end of the route (wells No. 538543) opened with a capacity of up to 7.0 m;

- coarse sand (ad IIIII) - light-grey, yellowish-grey in the zone of seasonal freezing, faint, frozen, mainly dense, wet in a thin state, dense, found on the segment of the first 16 km with a capacity of wells No. 8 and 9 from 2.0 to 4.5 m and on wells No. 37 and 38 from 0.5 m to 3.3 m in the valley of the stream;

- medium-sized sand (ad II) - gray, yellow-haired, quartz field-stepped in composition, weakly frozen in the seasonal freezing zone, frozen, dense, low-moisture, dense in a thin state, widely distributed on the first 13.5 km with a capacity of 2.8 m to 7.0 m;

- gravelly sand (ad II) - light-grey, brownish, yellowtoser, in the zone of seasonal freezing, frozen, weak-alder, dense, low-moisture, dense in the thalom state, met 5 km of the route by well No. 12 with an opened capacity of 1.5 m and then traced to well No. 29 with a maximum opened capacity of 2.5 m (squ.22). On one of the sections of the route it was opened by wells No. 372 and 376 with a capacity of 1.0 m, in the valley of the Peledu River it was met by wells 442 and 443 with a capacity of 2.0 m and 1.7 m, respectively;

- pebble soils with sandy aggregate (a I) - light gray, gray in the zone of seasonal freezing, frozen, weakly moist, low-porous, dense, distributed locally, met by wells No. 373 - 374 with a capacity of 5.0 - 2.0 m and wells No. 441 - 443 in the valley of the Peledu River, opened with a capacity of 2.8 - 8.8 m;

- soapstones (Є23vl+il) - not dismembered verkhnelensky and ilchinsky it is twisted, brown, henna-red, is more rare gray, in a zone of seasonal freezing jointed, low-strong, in a thawed state and in the conditions of permafrost thickness of average durability, are widespread on route pieces between wells: No. No. 3154, No. No. 78-88, No. No. 100105, No. No. 127-141, No. No. 191208, No. No. 303-327, at most opened power of 9.5 m;

- aleurolites (Є23vl+il) - brown, reddish-brown, sometimes greenish, low-strength in the zone of seasonal freezing, in melt and permafrost conditions of medium strength, enjoy limited distribution, are met on the section of the route from well No. 1 to well No. 5 with a maximum opened capacity of 8.0 m;

- sandstones (Є23vl+il) - light-gray, brown, sometimes reddish-brown, in the zone of seasonal freezing, fractured, low-strength, in melt and permafrost conditions of medium strength, are widespread, opened on sections of the route between wells: No. 6671, No. 86-190, No. 209302, No. 319-352, No. 374379, No. 443-453 at maximum open power - 9.8 m;

- limestones (Є23vl+il) - gray, light-gray, rarely greenish-gray in the zone of seasonal freezing, weak, fractured, medium strength, strong in melt and permafrost conditions, distributed mainly at the end of the route in sections, from well No. 383 to well No. 443, from well No. 454 to well No. 538 at a maximum revealed capacity of 9.2 m.

Permafrost soils are common on three sections of the designed route VL220 kV - from station 208 to station 332, from station 348 to station 569 and from station 679 to station 1054.

The detailed nature of the distribution of lithologostratigraphic differences in soils, their capacities, taking into account the boundaries of normative seasonal freezing - pouring and areas of development of permafrost rocks, is illustrated by engineering and geological sections of the longitudinal profile of the first line.

For the period of wells drilling, underground water to a depth of 10.0 m is not met.

Freezing ground conditions

The designed route VL 220 kV is located in the zone of intermittent, island distribution of permafrost rocks with a capacity of up to 70 m.

Well drilling established that in the section of the southern part of the route, starting from well 264 to well 543 (Peledui substation), permafrost soils are absent.

In the northern part of the designed VL, permafrost rocks are met by wells 5182 and south with a slight break by wells 86140. In the section between wells 141168 permafrost rocks are absent. Further, MMPs with a gap between wells 226240 are distributed in the section of wells 169260. The last island of permafrost rocks is met by wells 262 and 263.

Frozen soils, as a rule, have a massive cryogenic texture, rarely in loam there is a layered texture, the total ice content of frozen soils both in the zone of seasonal freezing and in permafrost thickness varies from 0.20 d units to 0.32 d units.

The temperature of permafrost soils (rocks) at the depth of annual heat rotations (10.0 m) is minus 1.3 ° С - minus 1.7 ° С.

Conclusions and recommendations

The route of the designed VL220 kV "Gorodskaya - Peledui" is located on the territory of the Lensky ulus and runs from the PS "Gorodskaya" in Lensk to the PS "Peledui."

Geostructurally, the survey area is located within the Siberian platform bordering the Aldan crystal shield, geocryologically - in the zone of mainly intermittent and island distribution of permafrost rocks.

Geomorphologically, the VL220 kV route is located within the Prilensky structural-denudation plateau and is a hilly row surface with absolute elevations along the wells of 193.84 m (squ.542) - 561.89 m (squ.221) in the Baltic altitude system.

Paleozoic formations of the Cambrian and Ordovian periods take part in the geological structure of the region and adjacent territories, everywhere covered by Cenozoic sediments represented by the lower, middle and upper Quaternary formations of the elluvial deluvial, alluvial-deluvial and alluvial genesis.

The detailed geological structure taking into account the boundaries of the normative seasonal freezing along the first line is illustrated by an engineering-geological section of the longitudinal profile.

The opened thickness to a depth of 10.0 m is divided into 44 engineering and geological elements.

Groundwater, for the period of research, to the studied depth has not been opened.

Uncemented quaternary deposits along the route are represented by EGE 2, EGE-4 loams, EGE 3, EGE-5 loams, sands from dusty to gravelly EGE 6 and EGE 11, mainly weakly molded, from hard to plastic in consistency. The power of these soils in the zone of seasonal freezing and seasonal pouring is relatively small - no more than 4.5 m.

The low capacity of quaternary sediments allows the use of bedrock (rock soils) as a base, especially in areas with intermittent and insular MMP distribution.

If there are rock soils in the foundation base and the permafrost does not develop in a continuous way, it is advisable to apply principle II (SNiP 2.02.0488).

On some sections of the route, MMPs of relatively high power are common. Here, taking into account the increased seismicity (6 points), the use of permafrost soils on principle I.

Engineering and geological conditions, mainly favorable for laying a high-voltage power line, are the widespread use of rock soils, mainly medium strength and other weakly compressed soils located deeper than the seasonal freezing zone.

The design and construction of foundations of shallow foundations (columnar types of mushroom-shaped footings) is possible on melted and frozen rock soils IGE13a - 16a and IGE13b - 16b, as well as on soils IGE4a -12a and IGE4b - 12b.

At the same time, it should be borne in mind that the soils IGE2 and IGE3 belong to the medium, and IGE4 and IGE5 belong to the low.

The construction of foundations of supports is possible on piles "posts," the bearing layer of which can be frozen and melted rocks of medium strength and strong.

Taking into account the fact that EGE-2, EGE-4 loams, as well as EGE-3 and EGE-5 sandy soils, should be used for backfilling.

The normative depth of seasonal freezing is reflected on engineering and geological sections, sheets 120 and varies from 2.5 m to 4.5 m.

Analysis of the engineering-geological section allows you to select foundations of supports of the type of footings, mainly 3.0 m high, in individual areas 5.0 m high, partially filled with non-sandy sandy soils.

Construction of supports No. 5872, 79-86, 209211, 217-222, 240249 and 286288 is better performed on piles resting on frozen and rock soils.

Calculation of foundation bases according to stability and strength on the effect of frost heaving forces shall be performed according to clauses 4.40 - 4.45, and the calculated specific tangent of the heaving force for IGE2 and IGE3 shall be taken equal to 70 kPa, and for IGE4 and IGE5 - 50 kPa.

Serial numbers of soil classification according to development difficulties shall be accepted in accordance with SNiP - Collection 1. Earthworks