Seafloor attachment bolts

摘要

A fastener assembly for securing structures to the seafloor including a shaft of circular cross-section having a frusto-conically shaped head on a leading end for insertion into a prepared borehole and a mandril section at the other end having annular grooves around its perimeter. An expansible sleeve is disposed around the shaft in interference fit with the borehole so that when the shaft is pulled upward, the head will force the expansible member to expand against the sides of the borehole. The shaft is disposed with the grooved section extending through an aperture in a workpiece and a malleable collar is positioned around the shaft resting on the workpiece. A conventional blind riveting installation tool may be used to pull the shaft upward to engage the expansible sleeve in the borehole and to swage the malleable collar to the grooved shaft against the workpiece.