Accession Number : ADA192162

Title :   Pumping-Erosion Subsidence of a Seafloor Plate-Footing.

Descriptive Note : Master's thesis,

Corporate Author : TEXAS A AND M UNIV COLLEGE STATION COLL OF ENGINEERING

Personal Author(s) : Grimmig, Alvin E , Jr

PDF Url : ADA192162

Report Date : Oct 1987

Pagination or Media Count : 163

Abstract : Subsidence of objects that rest on the seafloor is an expected but not well understood phenomenon. Subsidence is the settlement of fixed structures and mobile structures (such as oceanographic packages) that are placed on the seafloor. A major concern involving bottom resting systems, in relatively shallow water (less than 200 meters) is wave induced motions. The system response of the structure in this dynamic environment can create substantial loadings at the structure-seafloor interface. Past works have addressed wave-induced and current scour as the major factors causing structural subsidence, neglecting the effects of pumping - erosion. The research described is directed towards identifying and understanding the phenomenological asewcts of pumping-erosion. The work describes a new hypothesis concerning liquefaction as being the precursor to subsidence in a two cycle pumping-erosion process. Due to the complexity of structure-soil interaction a multivariable linear regression was performed on the data to substantiate experimental observations.

Descriptors :   *OFFSHORE STRUCTURES, *FOUNDATIONS(STRUCTURES), *SOIL EROSION, DYNAMICS, ENVIRONMENTS, EROSION, HYPOTHESES, LINEAR REGRESSION ANALYSIS, LIQUEFACTION, MOBILE, MOTION, MULTIVARIATE ANALYSIS, OCEAN BOTTOM, RESPONSE, SHALLOW WATER, STRUCTURES, WAVES, SINKING, PUMPING

Subject Categories : Soil Mechanics
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE