Abstract: A grouting and pile forming device includes a compartment box and a double-spiral-tube structure. The double-spiral-tube structure includes an outer spiral tube and an inner spiral tube, which are nested and fixed together. A top part of the outer spiral tube and a top part of the inner spiral tube are hermetically connected. An inner space of the inner spiral tube forms a grouting cavity. A space between the outer spiral tube and the inner spiral tube forms a drainage and delivery cavity. A plurality of drainage and delivery holes are provided in a tube body of the outer spiral tube. A construction method for strengthening soft soil through the grouting and pile forming device includes the following steps: 1) operation preparation; 2) downward spiral penetration; 3) drainage consolidation; 4) chemical consolidation; 5) upward spiral lifting; and 6) repeated operation until all soil to be strengthened is treated.

Abstract: An unloading type sinking rescue device of a subsea mining vehicle and a use method thereof are provided. The unloading type sinking rescue device includes an assembly support, an unloading system, an ejection system and a control system. The assembly support is box-shaped, fixed to a subsea mining vehicle, and provided with a plurality of enclosed cavities. The unloading system includes a counterweight, a counterweight cable, a counterweight fixing bracket and a counterweight recovery cavity. The ejection system includes an anchor, an ejection cavity, an anchor cable, an anchor recovery shaft, a pulley, a spring and a boosting device. The control system controls the operation of the unloading system and the ejection system. The use method includes: (1) unloading; (2) ejection; (3) recovery of a part of counterweights; (4) recovery of the anchor; and (5) recovery of remaining counterweights.

Abstract: An unloading type sinking rescue device of a subsea mining vehicle and a use method thereof are provided. The unloading type sinking rescue device includes an assembly support, an unloading system, an ejection system and a control system. The assembly support is box-shaped, fixed to a subsea mining vehicle, and provided with a plurality of enclosed cavities. The unloading system includes a counterweight, a counterweight cable, a counterweight fixing bracket and a counterweight recovery cavity. The ejection system includes an anchor, an ejection cavity, an anchor cable, an anchor recovery shaft, a pulley, a spring and a boosting device. The control system controls the operation of the unloading system and the ejection system. The use method includes: (1) unloading; (2) ejection; (3) recovery of a part of counterweights; (4) recovery of the anchor; and (5) recovery of remaining counterweights.

Abstract: A grouting and pile forming device includes a compartment box and a double-spiral-tube structure. The double-spiral-tube structure includes an outer spiral tube and an inner spiral tube, which are nested and fixed together. A top part of the outer spiral tube and a top part of the inner spiral tube are hermetically connected. An inner space of the inner spiral tube forms a grouting cavity. A space between the outer spiral tube and the inner spiral tube forms a drainage and delivery cavity. A plurality of drainage and delivery holes are provided in a tube body of the outer spiral tube. A construction method for strengthening soft soil through the grouting and pile forming device includes the following steps: 1) operation preparation; 2) downward spiral penetration; 3) drainage consolidation; 4) chemical consolidation; 5) upward spiral lifting; and 6) repeated operation until all soil to be strengthened is treated.