Sivand Dam
Introduction : Sivand river is originated from Kwh-Safid in south of Eghlid . It's general trend is south eastward till reaching to Ghader abad galley .After this galley it passes from the vicinity of Ghader abad and enters to morghab plain- and after passing from Kurd shul village enters to Tange Bolaghi and connects to Kur river at pole-khan .Sivand dam is constructed on this river at Tange-bolaghi with the following objectives .
1. Irrigation improvement of cultivated lands at both sides of this river from sivand dam to pole-khan.
2. Irrigation development of 1700 hectares in Saadat abad plain and 9000 hectares in Tavabe arsanjan plain.
3. Flood control to prevent inundation of cultivated loads in Korbal plain.
History : Water development plan of Bakhtegan basin started by Justin –cortini consulting engineers in the from of reconnaissance study in 1968.
This plan has been continued by Sakoo consulting engineers in 1986 in the from of Ghasrodasht irrigation and drainage and it's first phase has been approved by technical office of ministry of Energy.
After phase one approval diversion tunnel excavation and phase two study was started simultaneously and diversion tunnel operations was completed in 1993 by Sabir company.
Main dam body and it's appurtenant structures was started in 1993 by Pars-garma construction and industrial company . till now it's progress is more than 95 percent .
Geographical location : sivand dam is located in Tange-bolaghi about 80km north of Shiraz and 14km North-west of Saadat shahr in 53 05 longitude and 30 09 latitude.
Meteorological & Hydrological specifications
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Main Dam Body Specifications
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Dam type Rockfill with GC core |
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Dam crest elevation 1830 m asl |
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Dam foundation elevation 1773 m asl |
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Dam height from foundation 57 m |
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Dam crest length 600 m |
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Dam crest width 10 m |
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Upstream slope 1V : 2.5H |
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Down stream slope 1V : 2H |
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Core elope 2V : 1H |
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Core crest width 6 m |
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Main dam body fill volume 3120000 m3 |
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Core volume 1017000 m3 |
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Filter and drain volume 260660 m3 |
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Total fill volume 5100000 m3 |
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Dam width with upstream cofferdam at river bottom 320 m |
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Rackfill volume 2053000 m3 |
.For certainty of water tighting at the conjunction of grout curtain and core a partial plastic concrete cut-off was constructed with the following specifications :
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Depth of cut-off 5 m |
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Area of cut-off 2040 m2 |
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Tickness of cut-off 1.2 m |
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Volume of plastic concrete 2450 m3 |
Grout Curtain
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Length of grouting galleries Totally 2225m in the Right , left aboutments, Central parts |
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Shape of grouting galleries Horse shoe shape |
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Diameter of grouting galleries 3.8 and 3.1 m |
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Length of grout curtain in the dam axis 1600m(400m in alluvial foundation , 750m in the right abutment limestone 450m in the left abutment Limestone) |
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Depth of grout curtain 160m in alluvial foundation From river bottom 80m in the limestone abutments |
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Depth of grout curtain in the abutments 130m from the dam crest |
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Length of drilling for grouting 110000m (47000m in the alluvial foundation,63000m in the abutments |
Diversion and bottom outlet tunnel
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Length 260m |
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Excavation diameter 8.25 m |
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Completed diameter 7 m |
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Excavation area 53.43 m2 |
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Excavation volume 15500 m3 |
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Lining shotcrete , reinforced concrete |
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Shotcrete thickness 12.5 cm |
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Reinforced concrete thickness 50 cm |
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Forming operations 4000 m2 |
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Reinforcement operations 200 ton |
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Steel frames in and out of the tunnel 25 ton |
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Discharge capacity 466 m3/s |
Spillway Specifications
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Crest elevation 1821.5 m asl |
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Crest length 246 m |
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Chute width 40 m |
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Discharge capacity 6000 m3/s |
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Rock excavation 2500000 m (used in the |
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upstream cofferdam |
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and main dam) |
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Volume at concrete 150000 m3 (agree gats |
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from khersi borrow |
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area 20km upstream |
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north at the dam) |
Upstream Cofferdam Specifications
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Crest width 10 m |
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Upstream slope 1V : 2.5H |
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Downstrem slope 1V : 2H |
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Crest elevation 1806 m asl |
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Fundation elevation 1778 m asl |
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Height from foundation 33 m |
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Distance to dam axis 105 m |
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Core fill volume 400000m3 (transported |
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from borrow area 5.5km |
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upstream at the dam body) |
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Rockfill volume 1000000m3 (from spillway Excavation ) |
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Filter and drain volume 91000 m3 ( from khersi borrow area ) |
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Fill volume 1374000 m3 |
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Core slopes 2V : 1H |
