Seattle, WA SHORING * GROUNDWATER CONTROL * ENVIRONMENTAL

Transcription

1 Seattle, WA SHORING * GROUNDWATER CONTROL * ENVIRONMENTAL

2 Haiku is one of the most important forms of traditional Japanese poetry. Haiku is: a 17-syllable verse form consisting of three metrical units of 5, 7, and 5 syllables.

3 Haiku s are easy But sometimes they don t make sense Refrigerator

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6 $1.8 Billion, five year Mega project 13 miles of 17.5 diameter tunnel, 114 acre facility Shaft Freezing, break-in/break-out freezing, TBM rescue While most of the elements of the Brightwater project are on schedule, I am extremely concerned about the construction delays on the remaining two-mile segment of the outflow tunnel Dow Constantine King County Executive

7 History of Ground Freezing Ground freezing techniques were used by German scientist F. Hermann Poetsch, in It was first used in America by Chapin Mine Company in Iron Mountain, where freezing was performed to a depth of 100 feet. Over the years, the mining industry refined Ground Freezing techniques to successfully complete thousands of shafts all over the world. Some shafts over 2,000 feet deep. In the 1900 s freezing expanded into heavy civil construction helping complete many huge projects including: the Grand Coulee dam, the Chunnel, and Boston s Big Dig. Freezing became know as the method to use when all other methods failed. Why? Because Freezing nearly always worked but the cost was prohibitive.

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10 How Ground Freezing Works

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13 Manifolds and Freeze Pipes Before Freezedown During Freezedown

14 Electric Chiller Units - Size ranges from 20 to 500 tons of chilling capacity. Sized to fit each project. - Brine is chilled as it passes over baffles in specially designed chambers - Primary Refrigerant is R507 - Highly automated and very reliable

15 Instrumentation & Monitoring - Brine and ground temperatures at multiple depths are monitored and recorded daily. - Chillers controlled remotely. - Remotely monitored via internet connection Temperature [ F] CP-32, Surface Temperature Pipe: T-6 (Temp vs Time) T6: 58' bgs T6: 66' bgs 0 1Elapsed 2 Time 3Since Start 4 of 5Freezing 6 ( ) 7 8[week]

16 Frozen Soil Wall Formation

17 How Groundwater Cut-off is achieved Freeze Pipes Frozen Soil Groundwater Impermeable Soil Layer

18 Zone Freeze Technology (Patented)

19 Structural Shoring System 3 Diameter Steel Pipes Frozen Soil Full Excavation Profile View Cutoff Layer

20 Ground Freezing Engineering/Analysis Temp/W Plaxis 2D & 3D All shoring designs are stamped by a licensed engineer

21 Soils Analysis I SAND Bottom Of Excavation 22 BGS GRAVEL CLAY SILT 45 BGS (Bottom of Freeze)

22 Thermal Analysis

23 Design and Analysis

24 The freezing method is remarkably versatile and, with ingenuity, it can be adapted to a great many project conditions. Dr. Kamran M. Nemati, Professor in Construction Management and Civil Engineering at the University of Washington U.S. Environmental Protection Agency (EPA) - Frozen soil barriers are environmentally benign and have significant advantages over conventional containment systems using steel, concrete, slurry walls, or grout curtains and offer extremely low maintenance costs, allowing continued use for extended periods. EPA Site Technology Program, (7th edition, p. 202). Department of Energy (DOE) - Frozen soil can eliminate groundwater flow paths and the potential is great. (Scientific Ecology Group, Inc. for Martin Marietta Energy Systems, Document STD-R-00-01) Freezing to provide groundwater control and excavation support for shaft sinking remains the primary application. In fact, for deep shafts, no better method has yet been established. (The Constructor, Civil Engineering Publication) Ground Freezing is utilized in extremely difficult conditions where no other excavation support is feasible, and where cost is usually not a factor. Kennedy/Jenks Consultants

25 Advantages - Effective in all soil types (sand, gravel, silt, clay and peat or a mix soil condition)

26 * HKIE Civil Division International Conference 2012 icid: innovation and Creativity of infrastructure Developments for Quality Cities High Certainty of Uniformity

27 Advantages

28 Advantages

29 Adaptable

30 Eco- Conscious

31 Freeze Shoring Conventional Shoring Dewatering System Electrical Power Water Treatment Cost Water Disposal Cost Contaminates

32 Freezing For the Tunneling Industry

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34 Frozen Soil 23 ft

35 Freezing For the Tunneling Industry

36 Freezing For the Tunneling Industry

37 Freezing For the Tunneling Industry

38 Freezing For the Tunneling Industry

39 Freezing For the Tunneling Industry

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46 Soil Freezing for Effective Stabilization for TBM Rescues Case Study: Brightwater Regional Waste Water Treatment Plant $1.8 Billion, five year Mega project Located in King & Snohomish Counties, Washington 13 miles of 17.5 diameter tunnel, 114 acre facility Four contracts for Tunneling, Three Joint Venture Contractors

47 While most of the elements of the Brightwater project are on schedule, I am extremely concerned about the construction delays on the remaining two-mile segment of the outflow tunnel Dow Constantine King County Executive

48 The Fix Modify receiving shaft to become a launch shaft Modify and re-launch Elizabeth Stabilize Soil in front of and around the stuck Rainier TBM Completely gut Rainier including cutter face Drive Elizabeth over two miles to Intercept Rainier s tunnel alignment Drive Elizabeth into the empty shell of Rainier

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50 BT3 Junction Obstacles to Overcome Stuck under residential neighborhood 330 deep, 7 Bar pressure Geometry involved with freezing around TBM Electrical power (no 480 volt) Difficult / disturbed soil conditions

51 Project Location

52 BT3 Junction Freezing Freezing Around TBM to Remove Cutter

53 Freeze Pipe Installation

54 In-tunnel Drilling to Install Freeze Pipes

55 Figure 5. Elevation plot of thermal results near BT3 face with 4 freeze pipes activated below TBM

56 Main bearing Removal

57 Cutterhead Dismantling Frozen Soil

58 Fingers Crossed

59 Hole Through

60 Success