Ross Sea Hub Station Engineering Project

Background

The Ross Sea Hub Station Project is situated on Inexpressible Island in the southern region of Terra Nova Bay, Ross Sea, Antarctica. The project encompasses a total construction area of 5,244 square meters, comprising a main station of 3,107 square meters (three above-ground stories with a building height of 16.400 meters, utilizing a steel frame-bracing structural system) and a logistics center of 2,017 square meters (single above-ground story, employing a steel frame-cross bracing structural system).

Project Challenge

• Adverse Environmental Conditions: No external water supply sources are available in the Antarctic outdoor environment; water can only be sourced from Lake Mochou within the station area, with strict requirements for pollution control and water conservation. Seawater temperatures range from 0°C to -4°C with high salinity, imposing stringent demands on concrete corrosion resistance and setting performance. Concurrently, wave scouring risks necessitate comprehensive anti-scour protection measures for foundation works.

  
  

• High Construction Technical Complexity: Conventional cast-in-place form bag concrete placement is infeasible for underwater operations; precast components must be fabricated onshore and subsequently hoisted and sunk into position, with assurance of tight seams and close contact with steel sheet piles and existing structures for multi-layer form bag joints. Rock-embedded steel column construction demands strict control of borehole verticality and diameter (deviation ≤1%), requiring reduced-pressure, slow-advance drilling techniques. Underwater concrete placement must be completed within 30 minutes of borehole completion, imposing exceptionally high requirements for process coordination.

  
  

• Complex Material and Process Adaptation: Specialized concrete formulations must be developed and adapted for the Antarctic low-temperature, high-salinity environment, requiring iterative mix proportion adjustments and optimization of retarder and water-reducer components. The concrete must simultaneously satisfy initial setting time ≥120 minutes, final setting time ≤240 minutes, and strength requirements under both ambient temperature and -4°C low-temperature conditions. Connection of steel structures to existing semi-high box wharves demands precision welding, with steel sheet pile enclosure, rubble filling, and other multi-process operations requiring synchronous coordination; obstructive steel beams must be promptly removed as necessary.

  
  

• Stringent Quality Control Requirements: Form bag concrete placement is prone to excessive pressure-induced bulging and detachment, as well as incomplete filling, necessitating continuous monitoring throughout the process. Indicators including steel casing and rock-embedded pile verticality, concrete strength, and corrosion resistance performance require comprehensive control. Given the absence of adequate on-site testing conditions, water-reducer and retarder components must be pre-separated for flexible on-site adjustment based on actual conditions.

Solution from ARIT

To accommodate the variable on-site testing conditions, ARIT coordinated with the client to separately ship water-reducer components and retarder components, primarily comprising our proprietary products ART-M63, ART-M15, and ART-Retarder A. Based on cement properties and on-site materials and environmental conditions, systematic mix design adjustments were conducted. Through form bag concrete compatibility testing, optimal concrete performance was achieved with satisfactory fluidity meeting placement workability requirements. The setting time requirements were fully satisfied (initial setting time ≥120 minutes, final setting time ≤240 minutes). Under ambient temperature curing conditions, 1-day compressive strength exceeded 30 MPa; under low-temperature conditions of -4°C, strength approached 20 MPa. All performance parameters substantially met client requirements.

Product from ARIT

• ART-M63, ART-M15, and ART-Retarder A

For detailed remixing formula, feel free to contact technicians of ARIT