Penetration of free-falling objects into deep-sea sediments

By

Carlmark, Jon William.

Type

Book

Material

Published material

Publication info

Notes

Thesis advisor: Smith, R.J.

"December 1971."

DTIC Descriptors: Salvage, Falling Bodies, Ocean Bottom, Penetration, Impact, Submarines, Ocean Bottom Topography, Instrumentation, Sedimentation, Free Fall Models, Mathematical Models, Computer Programs, Theses, Theses.

IDE: Impact, Water.

Thesis (M.S. in Ocean.)--Naval Postgraduate School, 1971.

A rational method is presented to predict the penetration of free-falling objects into deep-sea sediments by combining proven empirical theories from the field of soil mechanics with known hydrodynamic phenomena. The impact velocity of the object and the shear strength profile and density of the sediment are assumed to be known. The penetration problem was solved through the use of a computer by equating the work done during penetration to the energy of the object falling through air and impacting onto a modeled deep-sea sediment. The objects were simple geometric shapes ranging in weight from 500 to more than 1,000 pounds. The impact velocities ranged from zero to twenty feet-per-second. The results are compared with full scale tests and recommendations are made to extend the method to a water-sediment interface. The method successfully predicts the penetration of objects into weak, saturated, sediments within the accuracy of the stateof- the-art techniques for measuring the sediment mechanical properties. The impact duration time was observed to be relatively constant and independent of object velocity, shape, and weight implying that it may be a unique property of the dynamic behavior of a sediment type.

Subjects

Oceanography

Call Number

C225

Language

English

Identifiers

DOI: https://doi.org/10.5962/bhl.title.59863
OCLC: 640309132
Wikidata: https://www.wikidata.org/entity/Q51517211