Showing papers on "Submarine pipeline published in 1968"

The southern Monterey Bay littoral cell: A preliminary sediment budget study

Abstract: A sediment budget was developed for southern Monterey Bay, California. This budget is based heavily upon sediment information obtained from field and laboratory studies. These studies included a detailed quasi-synoptic areal sampling to determine distribution of textural patterns, and a time-series study of beach and surf-zone sand samples obtained from local sand-mining companies. Results from these studies were combined with data on river discharge, the wind and wave regimes, and shoreline changes during the past century to develop quantitative estimates of sediment gains and losses to the cell. It was determined that the major sources of sediment are the discharge from the Salinas River which empties into the northeast corner of the cell, and erosion of Quaternary seacliffs which form the inner bay shore. Major sinks are the Monterey Submarine Canyon, active coastal dune fields, the mining companies, and the offshore area. The recent history of the sediment regime in the southern bay is reviewed, and a forecast of future nearshore changes is made. Recommendations for further work needed to refine the budget computations are presented.

Polygenetic Origin of Monterey Submarine Canyon

Abstract: Monterey Submarine Canyon, one of the world's largest and deepest, heads immediately offshore in Monterey Bay on the central California coast. Starke (1956) reported the presence of a deep buried canyon inland from, and aligned with, the head of the submarine canyon. Cumulative well records, gravity surveys, and field investigations strongly suggest that the buried ancestral canyon was eroded by fluvial processes, and that the present submarine canyon originated, at least in part, by the fluming out of the ancestral canyon by dominantly submarine processes. Other submarine canyons off unstable coasts may also be polygenetic in origin. The presence of the ancestral canyon provides additional information on the deformational history of this part of the central California coast.

Pipe Soil Interaction For A Buried Offshore Pipeline

Abstract: A research program to develop design criteria for the elimination of offshore pipeline movements showed that pipeline interaction with the supporting soil is affected by such parameters as the size and weight of the line, the character of the soil, the method of installation of the line, the kinds of fluids pumped through the line, the temperature variation of the line, the possible vibration of the line, the currents in the water at the ocean floor, the initial tension in the line, the possible upward flow of water in the vicinity of the line, the geometry of the line, the geology of the area, the depositional environment (including possible submarine flowslides), and the possible scour or sedimentation at the ocean floor.

Rational design of submarine pipelines

Abstract: This paper discusses the problem of establishment of criteria for analyzing environmental data, and the stability conditions of a pipeline when it is suspended from the surface, resting on the bottom, spanned above the bottom, or embedded in the bottom. Once these criteria are established and the appropriate environmental climate is known, the pipeline can be designed and its economics examined. The paper describes methods for obtaining information on soils and currents, the interpretation and analysis of this data, establishment of the foundation for the pipeline, other environmental factors, and the use of this data applied to the pipeline design. The author categorizes the environmental factors to be determined on the basis of evaluation during construction, and evaluation during the useful life of the pipeline. Factors to be considered during the design evaluation phases are summarized in conclusion.

The effects of waves and currents on submerged pipelines

Abstract: This paper discusses some extreme environmental factors acting on submarine pipelines. A brief discussion of the theoretical considerations for such factors as scour and hydrodyanmic forces or forces experienced during the laying operation on both buried and unburied pipelines is presented. Also, a review of the literature concerned with theory, laboratory studies, and field experience with regard to the submarine pipeline problem is provided. Certain aspects of design, including route selection, laying methods, pipeline burial, and pipe risers, are examined. Translations of foreign literature, abstracts, and an annotated bibliography of selected sources pertaining to theoretical and experimental studies and steps being taken to minimize failures and installation costs are compiled for readily available reference. This literature survey includes a comprehensive list of recommendations for further research as prepared in a report by the Committee on Research, Pipeline Division of the American Society of Civil Engineers.

Beach Rehabilitation by Hopper Dredge

Abstract: The field experiment conducted by the U. S. Army Corps of Engineers to determine the feasibility of rehabilitating ocean beaches by employing hopper dredges to unload and pump ashore sand directly from their hoppers, through a submerged pipeline, while moored offshore in the ocean environment is described. The plant and equipment used and the operational experience and results obtained are illustrated and described. Possible future application of the operational technique developed is indicated.