Subsurface micro-tunneling operations in dense urban environments require continuous ground stabilization to prevent structural settling. While high-pressure jet grouting is frequently deployed to consolidate loose sandy strata, engineers increasingly rely on artificial ground freezing for water-saturated soils. In this process, closed-loop refrigeration pipes circulate chilled brine at sub-zero temperatures, freezing pore water into an impermeable ice-soil matrix. Although the refrigeration units consume immense electrical power and require round-the-clock thermal monitoring, the frozen perimeter provides temporary compressive strength and absolute water cutoff. Ultimately, ground freezing provides a reliable, impermeable barrier that enables safe underground excavation where conventional chemical grouting methods fail.
Which of the following best expresses the main idea of the passage?
- AHigh-pressure jet grouting is deployed to consolidate loose sandy strata during micro-tunneling.
- Artificial ground freezing serves as an effective temporary stabilization method for tunneling through water-saturated ground.Cevap
- CClosed-loop refrigeration pipes circulate sub-zero brine to freeze pore water into an ice-soil matrix.
- DGround stabilization methods eliminate all geotechnical hazards and settlement risks in urban excavation.