The document discusses problems and solutions for designing roadway and railway networks in permafrost regions. It first defines permafrost as soil or rock that remains frozen below 0°C for two or more years. It then discusses where permafrost is located, why it thaws, and problems that occur when it thaws, such as damage to infrastructure. Various engineered solutions for roads and railways are presented, including thermosyphons, ventiduct embankments, stone embankments, and dry bridges, which aim to prevent thawing by reducing heat transfer to the ground. The China Railway Line case study demonstrates challenges with building railways across discontinuous and continuous permafrost.

1. Problem And Solutions In Design OfProblem And Solutions In Design Of
Roadway And Railway Network In Permafrost RegionRoadway And Railway Network In Permafrost Region
A Seminar on
By
Ashish Parihar
Roll no. 141701
M.Tech. (Transportation Engineering)

2. Overview
• What is Permafrost?
• Where Permafrost?
• Why does permafrost thaw?
• What happens when permafrost thaws?
• Key Terms and Landforms
• Case Study
• Engineered Solutions
• Summary
• References
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3. What is Permafrost?
 Soil or rock that remains below 0°C throughout the year, or may be for two
or more years.
 Ice is not always present, frequently occurs
 Moisture in the form of either water or ice may or may not be present.
 Permafrost may therefore be unfrozen, partially frozen, or frozen
depending on the state of the ice/water content.
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4. What is Permafrost?
PermafrostPermafrost
Source: http://wiki.fis-ski.com/index.php/Permafrost
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5. Where Permafrost?
 North America
 Scandinavia
 Russia
 China
Some Estimated Depth:
• 440 m in Barrow, Alaska
• 600 m in the Canadian Arctic Islands
• 1493 m in the northern Lena and Yana
River basins in Siberia
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6. Why Does Permafrost Thaws?
Changes occur due to:
oSoil compression,
oChanging drainage of soil,
oClimatic changes,
oTemperature changes
 Solar heating of the surface,
 Temperature of pavement
surface,
Source: http://www.scienceinschool.org/2012/issue22/permafrost
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7. “No ground to stand on”
 Travel Problems
 Increasing road hazards & damage
 Shorter travel season
 Railways shift and bend
 Airport runways crack
 More Geohazards
 Landslides,
 Debris & mud flows
 Subsidence
Source: http://wiki.fis-ski.com/thawingeffects.php
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8. • Permafrost:
• Continuous Permafrost:
• Discontinuous Permafrost:
 Permanently frozen ground
 Temperatures have remained below 0 °C for at least 2 years
 Mean annual air temperatures of below -5 °C all year,
 as low as -50 °C.
 Slightly warmer areas
 Islands of permanently frozen ground separated by small
pockets of unfrozen less cold areas.
 Mean annual temps of between -1 °C and -5 °C
Key Terms And LandformsKey Terms And Landforms
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9. Source: http://www.scienceinschool.org/2012/issue22/permafrost
Key Terms And LandformsKey Terms And Landforms
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10.  Summer temperatures sufficient to melt
 This layer can be very mobile
 It varies in thickness depending on latitude and vegetation cover.
 Any unfrozen material within the permafrost zone.
• Active layer:
• Talik:
Key Terms And LandformsKey Terms And Landforms
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11. Case Study
Source: http://www.chinatibettrain.com/aboutus.htm
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12. China Railway Line
 QINGZANG ( Qinghai - Tibet) Railway nearly 1200 mile
 Stations name :- Xining to Lhasa
 Approximately 1300 miles of the new railway in between Golmud to Lhasa was having
 Continuous
 Discontinuous Permafrost
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13. Engineered Solutions
1) Active method : To destroy
permafrost section completely.
2) Passive method : It Functions to
reduce heat absorption.
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14. •Thermo-Syphon
•Ventiduct Embankments
•Air-Cooled Stone Embankment
•Awning/ Shading Boards
•Expanded Polystyrene Insulation
•Dry Bridges
Engineered Solutions
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15. Thermo-Syphons
 Pressurized Cylindrical tube and
 Filled of low boiling point.
 Dissipation of heat by:
 Evaporation
 Condensation of liquid.
 These are best utilized for high risk sides
 Unstable permafrost.
Source: http://info.tibet.cn/en/news/phn/pnt/t20060605_120583.htm
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16. Thermo-Syphons
Source: https://www.thermalfluidscentral.org/encyclopedia/index.php/Two-Phase_Closed_Thermosyphon
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17. Ventiduct Embankments
 Inclusion of pipes serving as air culverts .
 Can increase heat absorption with in the embankment.
 Requires natural wind current to remove heat from the
embankment.
Source: http://info.tibet.cn/en/news/phn/pnt/t20060605_120583.htm
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18. Air Cooled Stone Embankments
 Poorly graded aggregates are used to create pore spaces.
 Rock layer act as thermal insulating barrier
 Block stone embankments utilize large aggregates
 Roughly 8-12 inches in diameter
 Crushed rock embankments use smaller aggregates
 3-4 inches in diameter.
Source: http://wiki.fis-ski.com/index.php/heat_transfer
17

19. Rock Embankment Configurations
Air Cooled Stone Embankments
Source: http://info.tibet.cn/en/news/embkmnt/pnt/t20060605_120583.htm
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20. Awnings And Shading Boards
 Primary function Is to reduce solar radiations.
 Water infiltration and snow accumulation are minimized.
Source: http://www.scienceinschool.org/2012/issue22/permafrost/awnings_shading.htm
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21. Awning
Awning configurations
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22. Dry Bridges
 Pile lengths of 25 to 30 m,
 Pile diameters of about 1.2m,
 Utilizes a negative friction force
 To ensure engineering stability,
 Ignoring the carrying capacity of pile
 Permafrost thaw problems. Er’a’ga dry bridge on Muli Railway, China
Source: http://wiki.fis-ski.com/index.php/Permafrost
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23. SUMMARY OF ENGINEERED SOLUTIONS
Engineered
Solution
Expected Outcome Potential Drawbacks
Cost ($/100 track
feet)
Thermosyphons
High risk sites, unstable
permafrost, useful for transitional
zones
Damage during transport or
installation, obstruction of fins,
maintenance potential
$27,500-$30,800
Ventiducts
Embankments
Minimize differential settlements,
reduce internal temperature of
embankment
Blockage due to snow or debris,
minimized performance due to
settlements, water ponding,
maintenance potential
$9,800- PVC
$16,500- Concrete
$23,750- Metal
Block Stone
Embankments
Increase convection cooling of
entire embankment, increased full
width embankment stability
Plugging due to snow or fines,
settlements risk $44,800
Crushed Rock
Revetments
Convection cooling of shoulders,
stability of shoulder sections
Warming in centre of embankment
with cooling of shoulders (differential
settlement), plugging due to snow or
fines
$12,000 22

24. SUMMARY OF ENGINEERED SOLUTIONS
Engineered
Solution
Expected Outcome Potential Drawbacks
Cost ($/100 track
feet)
Awning/
Shading Board
Reduce solar radiation,
minimize water infiltration,
improve convection cooling
Damage due to natural or
manmade occurrences,
maintenance potential
No Data
Extruded
Polystyrene
Minimize heat influx into soil,
reduce frost penetration
depth, minimize construction
depth
Water absorption, mechanical
damage, decreasing insulation
performance $2,300
Dry Bridge
Ensure stability during
permafrost degradation,
eliminates settlements and
thaw consolidation
Differential settlements of
columns, damages due to natural
or manmade occurrences $1,040,000
23

25. Summary
 Should be part of the planning of any engineering project in the north.
 It is best to disturb the permafrost.
 Thawing make soils more stable for future construction.
 Costs of continual maintenance vs. initial cost of advanced
engineering solutions
 How rapidly can permafrost thawing be expected to occur?
 Special attention has been paid to ground temperature and ice
content.
24

26. References
 Cheng, G. D. _1984_. “Problems on zonation of high-altitude permafrost.” Acta Geogr. Sin., 39_2_, 185–
193 _in Chinese; Abstract in English_.
 Cheng, G. D. _2003_. “The effect of local factors on spatial distribution of permafrost and its revealing to
Qinghai–Xizang Railroad design.” Sci. China (Ser. D), 33_6_, 602–607.
 Cheng G. D. _2005_. “A roadbed cooling approach for the construction of Qinghai–Tibet Railway.” Cold
Regions Sci. Technol., 42_2_, 169–176.
 Ding, Y. J. _1998_. “Recent degradation of permafrost in China and the response to climate warming.”
Proc., 7th Int. Conf. on Permafrost, Univ. of Laval, Yellowknife, Canada, 225–230.
 Lai, Y. M., Zhang, L. X., and Zhang, S. J. _2003_. “The cooling effect of ripped-stone embankments on
Qinghai–Tibet Railway under climatic warming.” Chin. Sci. Bull., 48_6_, 598–604.
 Research Group of the Qinghai–Xizang Highway. _1983_. “Distribution regularities of high-ice-content
permafrost along Qinghai–Xizang Highway.” Proc., 2nd National Conf. on Permafrost, Gansu Cultural
Press, Lanzhou, China, 43–51.
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27. References
 Tong, C. J., and Wu, Q. B. _1996_. “The effect of climate warming on the Qinghai–Tibet Highway.” Cold
Regions Sci. Technol., 24_1_, 101–106.
 Wang, S. L., Zhao, X. F., Guo, D. X., and Huang, Y. Z. _1996_. “Response of permafrost to climate change
in the Qinghai–Xizang Plateau.” J. Glaciol. Geocryol., 18 _Special Issue_, 157–165 _in Chinese_.
 Wu, Q. B., Liu, Y. Z., and Tong, C. J. _2003_. “Interaction between frozen soil and engineering in cold
regions.” J. Eng. Geol., 8_3_, 281–287.
 Sheng, Y., et al. ~2002b! “Application of thermal-insulation treatment to roadway engineering in
permafrost region.” J. Glaciol. Geocryol., 24~5!, 618–622.
 Slater, A. G., Pitman, A. J., and Desborough, C. E. ~1998!. “Simulation of freeze-thaw cycles in a
circulation model land surface scheme.” J. Geophys. Res., [Atmos.], 103~D10!, 11303–11312.
 Smith, M. W., and Riseborough, D. W. ~1996! “Permafrost monitoring and detection of climate change.”
Permafrost Periglacial Process., 7~4! 301–309.
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