GROUND FREEZING FOR CIVIL APPLICATIONS

SoilFreeze has designed cost effective solutions to a broad range of subsurface problems for general contractors and their clients.

• I-405/SR-522 Stormwater Detention Vault—Woodinville, Washington
• Madison Park Condominium Basement—Seattle, Washington
• Terminal 5 Pipe Repair—Seattle, Washington
• Boring Machine Recovery—Renton, Washington
• Boring Machine Receiving Pit and Storm Line Tie-in—Renton, Washington
• Remedial Excavation at Shuffleton Substation—Renton, Washington
• Microtunnel Receiving Shaft, Tolt Pipeline #2 at Bear Creek Crossing—Redmond, Washington
• Arapahoe Coal Handling Facility—Englewood, Colorado
• Canterbury Castle Underpinning—Portland, Oregon
• Soos Creek Sewer Lift Station #38—Maple Valley, Washington
• Dockside Handling Building D5 Service Unit Training Pit—US Navy Subase, Bangor, Washington
• Microtunnel Receiving Shaft, Tolt Pipeline #2 at W. Snoqualimie River—Redmond, Washington
• Tunnel Through Railroad Embankment—The Dalles, Oregon
• Olympic Pipe Line Company East Creek Reroute—Bellevue, Washington
• Shoring and Groundwater Cutoff at Shear #2 & #3, Nucor Steel —Norfolk, Nebraska
• Four Microtunnel Shafts, LA Harbor Sewer Relocation—San Pedro, California
• Mallard Bay Sewer Lift Station—Sammamish, Washington
• Lake Sammamish Sewer Interceptor—Sammamish, Washington
• Gravity Wall for Container Wharf —Pasadena, Texas
• Sewer Manhole Replacement—Los Angeles, California
  

In each of these projects, SoilFreeze was called upon to provide shoring and groundwater cutoff to facilitate excavation, construction and other activities on sites with a high water table.

Promotion of ground freezing applications in the civil engineering arena will feature the soil stabilizing capability of the technology and its cost-effectiveness in achieving a desired result. The strength of frozen ground is usually higher than that of concrete. This capacity to bear stress plus the ability to block water flow makes frozen ground very effective for shoring in wet loose soils.

Historically, ground freezing for civil (non-environmental) application has been used primarily on large complex projects where groundwater and caving soils create an unstable situation and ground freezing represents the only possible solution. An example is the Washington D.C. subway. Ground freezing was used to stabilize excavation walls in caving soils and to prevent groundwater seepage into the deep excavations near existing structures. The technology has been applied in Europe and North America for more than a century resulting in hundreds of documented cases where temporary ground freezing has been employed on a variety of construction and mining projects.

The present ground freezing technology used worldwide by most ground freezing companies is based on quick freezing using circulating brine or, in some cases, liquid nitrogen. These methods are fast but very expensive and utilize large equipment with high electrical requirements. In late 1996, RKK completed development of a methodology that allows the use of smaller pipes, smaller refrigeration equipment. The design can be modified to freeze quickly, if needed, or slower at less cost if time permits. The cost savings over conventional freezing systems currently being used in civil applications is significant.

The Company plans to expand ground freezing from the previous conventional large scale applications into the following civil markets specifically targeting small and intermediate size projects:

Ground Freezing For Shoring And Groundwater Cutoff

• Shallow Excavations—Natural groundwater cutoff at shallow depth
• Shallow Excavations—No natural groundwater cutoff at shallow depth—Small Site
• Shallow Excavations—No natural groundwater cutoff at shallow depth—Large Site
• Deep Excavations—Natural groundwater cutoff near bottom of excavation
• Tunneling
• Groundwater Cutoff Wall

Other Civil Applications

• Recovery of Underground Boring Machines
• Access Shafts For Boring Machines
• Underpinning Existing Structures
• Stabilization Of Soft Ground
• Landslide Stabilization
• Liquefaction/Contamination Mitigation