Abstract: For firm installation at a water bottom, a mooring anchor for securing a basal end of a mooring line underwater includes an anchor assembly to which the mooring line is to be fastened, and installable at a water bottom, and a guide to be secured at the water bottom at a position away from the anchor assembly and including a holder to receive and hold the mooring line in a movable manner. The anchor assembly includes a pile drivable into the water bottom and a tilted support extending obliquely downward toward the guide at the water bottom and to be embedded in the water bottom, such that the tilted support withstands and overcomes a tensile force acting in a horizontal direction.

Abstract: A simplified structure allows inspection of the installation strength of an anchor installed underwater. A method includes applying, to an anchor, a lifting force from above a floating body floating on a water surface to submerge the floating body into water, and setting a volume of submergence by which the floating body is submerged to a value to produce a lifting force corresponding to a predetermined installation strength and determining whether the anchor is immovable. The volume of submergence by which the floating body is submerged to produce the lifting force corresponding to the predetermined installation strength is calculated based on the buoyancy acting on the floating body.

Abstract: For firm installation at a water bottom, a mooring anchor for securing a basal end of a mooring line underwater includes an anchor assembly to which the mooring line is to be fastened, and installable at a water bottom, and a guide to be secured at the water bottom at a position away from the anchor assembly and including a holder to receive and hold the mooring line in a movable manner. The anchor assembly includes a pile drivable into the water bottom and a tilted support extending obliquely downward toward the guide at the water bottom and to be embedded in the water bottom, such that the tilted support withstands and overcomes a tensile force acting in a horizontal direction.