Use of the underground in Norway

Transcription

1 Lecture at Nanyang Technical University 13th January 2015 Use of the underground in Norway Professor emeritus Einar Broch NTNU; Norwegian University of Science and Technology Trondheim, Norway 1

2 Geology of Norway Two thirds: Precambrian rocks. Gneiss dominating (granites, gabbros and quartzite). One third: Paleozoic rocks. Gneisses, mica-schists and greenstones + sandstones, shales, limestones. Typical hard rock province. Folding, faulting and high tectonic stresses influence the stability in tunnels and underground caverns 2

3 Use of the underground in Norway, - some key figures Norway has today 200 underground powerhouses and 4000 km of tunnels for the hydropower industry The number of railway tunnels is approximately 800, the longest being 14 km The number of road tunnels is approximately 1200, the longest being 24,5 km. The World s largest cavern for public use, the Gjøvik Olympic Mountain Hall has a span of 61 m and can seat 5500 persons. 3

4 Use of rock caverns in urban areas Storing of food, water, oil, pressurised gas, industrial waste and several other products. Industrial installations like powerhouses, factories, telecommunication centres. Municipal installations like treatment plants for drinking water and sewage, and car parks. 4 Entertainment and recreation like sports halls, swimming pools, art centres, theatres, etc. War protection - Air raid shelters.

5 1. CAVERNS FOR STORING Oil and other liquid hydrocarbons Pressurised gas and air Water Food Grains and vegetables at refrigerator temperatures. Fish, meat, ice cream, etc., at deep freezer temperatures. Industrial waste Others: Coal, sand, archival, art, wine, beer, etc 5

6 6 Oil tanks in the Trondheim harbour

7 7 Underground oil caverns

8 Dimensions for oil caverns Oil caverns in reasonably good rocks normally have a span of m, a height of m and lengths from 200 to 500 m. Two to five parallel caverns is quite common. To prevent leakage of oil and/or gas through the rock mass, a water curtain is established above and around the caverns. 8

9 9 Water curtain is established above and around the caverns.

10 Overview gas storage Project Commis Main Storage Temp. sioned rock vol. m 3 o C Rafnes 1977 Granite Mongstad 1989 Gneiss Mongstad 1999 Gneiss Sture 1999 Gneiss Kårstø 2000 Phyllite Mongstad 2003 Gneiss

11 11 Mongstad propane storage

12 12 Steinan water cavern, Trondheim

13 13 Steinan water cavern, Trondheim

14 14 The Høgåsen underground water tank, Trondheim

15 Factors which may favour an underground solution for drinking water tanks are: High degree of safety, also against war hazards, sabotage and pollution. Constant and low water temperature. Low or no addition in price for a two chamber solution. The excavated rock masses may be used for other purposes. Very low maintenance costs. 15

16 Underground deep freeze storages LOCATION VOLUME ROCKTYPE TEMP. YEAR m3 oc Ekeberg, Oslo Granitic gneiss Brevik Limestone Gjelleråsen, Oslo Syenite Hamar Gneiss Jordalen, Bergen Gneiss Stathelle Limestone Trondheim Greenstone Jordalen, Bergen Gneiss Stathelle Limestone

17 17 Deep freeze cavern for storage of food Width: 15, length: 85, heigth: 8.6 m Temperature: - 26 degrees C

18 18 Deep freeze cavern for storage of food

19 Factors which may favour an underground solution for cold store caverns for food are: In Scandinavia the energy consumption for deep freezer stores is 75% and for refrigerator stores only 25% of similar surface stores. The peak energy requirements, and thus the installations, are even more favourable. The deep freezer storage will need 50% and the refrigerator storage only 20% capacity of similar surface stores 19 Strongly reduced insurance rates are also favouring the subsurface solution for cold stores,

20 20 Storage of industrial waste at Odda

21 2. CAVERNS FOR INDUSTRIAL INSTALLATIONS Powerhouses for hydro, thermal or nuclear power Factories Telecommunication centres 21

22 22 Modern underground hydropower station

23 23 Underground factory

24 3. CAVERNS FOR MUNICIPAL INSTALLATIONS. Water treatment plants Sewage treatment plants Car parks (not discussed in this paper) 24

25 25 Oset water threatment and pumping plant, Oslo

26 26 Oset water threatment and pumping plant, Oslo

27 27 Høvringen underground sewage treatment plant, Trondheim

28 4. CAVERNS FOR ENTERTAINMENT AND RECREATION Theatre and cinema Concert halls Sports halls and gymnasiums Swimming pools Ice hockey rinks Restaurants 28

29 29 Odda Mountain Hall

30 30 Gjøvik underground swimming pool

31 31 Gjøvik Olympic Mountain Hall

32 32 Underground installations in Gjøvik

33 33 The Gjøvik Mountain Hall Width: 61, Length: 91, Height: 25 m

34 34 Holmlia sportshall and swimming pool, Oslo

35 35 Holmlia sportshall and swimming pool, Oslo

36 Norwegian contract practice The Owner carries the risk for the ground conditions The Owner is responsible for the collection of information on ground conditions. All information is disclosed to the tendering contractors for their own interpretation. The Owner provides his interpretation of the situation in terms of estimates on quantities on rock support, The Contractor carries the risk for the appropriate and efficient handling of the works and focus on improving his technical and organisational performance. The contracts include regulations for extension of construction time based on actually performed quantities. 36

37 37 Risk sharing principle

38 Concluding remarks Mountains and hills have often been regarded as as obstacles by city planners The underground will become an increasingly more valuable resource in urban areas This presentation has shown some examples of how the underground is used. Only the fantasy sets a limit to how the underground may be used 38

39 39 The Tunnel to and from Hell