Geotechnical

The objective was to assess the feasibility and costs associated with pipeline construction in deeper and more exposed areas of the Beaufort Sea, Alaska as contained in Lease Sale 87. This study addressed the prime concerns for construction of pipelines in the Arctic: (1) establish feasible techniques for pipeline construction in Outer Continental Shelf (OCS) Lease Sale 87, (2) identify new concepts for deep water ice covered conditions, and (3) develop cost data to be used for oil and gas development plans.

This was a Joint Industry Project (JIP) with the U.S. Army Corps of Engineers, Waterways Experimental Station (WES) and Texas A&M University; to study parameter trends and phenomenological aspects of the moving soil sediment/pipe interaction problem. Research consisted of characterizing the viscous drag of soft soils on embedded pipelines. Equations were developed for soft soil. The soil pipeline interaction was validated with model experiments at Texas A&M University.

A state-of-the-art study was conducted, including a review of current design procedures and recent research data. Limit state criteria and the uncertainty in the determination of the relevant structural response parameters were assessed based on current available information. Problem areas were identified with an assessment of the ability of current technology to deal with these problems. Areas where additional information is needed to increase our capability to determine the reliability of gravel mat foundations were also identified.

The objective was to analyze seafloor earthquake motion data for seismic active areas of southern California and the Arctic. The program focused on the use of the seafloor Earthquake Measurement System (SEMS) to collect and store seafloor seismic events. Offshore ground motions may differ from onshore motion in several aspects:

(1) Attenuation factors may be different in saturated soft and/or gassy seafloor soils;

(2) wave reflection within the water column may alter site-specific wave column;

(3) the wave reflection pattern may differ due to soil profiles; and

This was a Joint Industry Project (JIP) that was sponsored by 18 oil companies with MMS. The project addressed the environmental criteria required to study alternative drilling, production, and transportation systems appropriate for permanent development of three Bering Sea Basins: St. George, North Aleutian, and Navarin. The project will provide an identification of major engineering problems, constraints, and information needed to allow development of three stated basins. Project No.

This was a joint industry-wide cooperative research project; it was composed of 15 different organizations. The general purpose of the project was to evaluate the safety against foundation failure for jack-up platforms. The research is being conducted to gain a better insight into the soil-structure stability phenomenon and how it related to the overall response of the structure. Current design procedures will be analyzed to define critical parameters and proposed measures to reduce risk and improve reliability.

This is a Joint Industry Project (JIP). A program of static and slow cyclic lateral load tests on piles in sand were conducted on two existing instrumented steel pipe piles installed in a uniform saturated silty sand at Seal Beach, California. Pile moments and head deflections will be obtained for different load conditions and pile head restraints. Emphasis will be placed on the acquisition of high quality data and on their subsequent analysis and interpretation.

To study designs of tension-leg platforms (TLP); to understand how platform foundations interact with the soil to influence the stability and reliability of the platform; to identify research topics and to initiate work on topics identified as being critical.

This was a joint Industry Project (JIP) to study the response of clay soils to the deflection of a pile with large, lateral cyclic loading and erosion of stiff clay due to repeated lateral loading. Studies involve an evaluation of the continuum mechanics and the finite element methods, and the P-Y method, in solving the problem of determining soil response for offshore structures. In-situ data and undisturbed samples for laboratory testing will be obtained from sites where major pile experiments were conducted.

To develop an improved correlation between measured soil properties and maximum load transfer in single piles and to improve the understanding of load transfer mechanisms in single piles and pile groups in cohesionless soils. This is a companion study to Project No. 45. The purpose of this study is to consider the geotechnical problems associated with the foundation supports for tension-leg platforms.