Structures

This project's objective was to organize and conduct a Underwater Welding Seminar with representatives of MMS, PEMEX, IMP, and other interested parties. The seminar considered the different aspects of underwater wet welding of offshore oil and gas platforms typical of those located in the Gulf of Mexico (GOM). The seminar identified technical and non-technical barriers that hinder the use of the technology for fabrication and maintenance of platforms and pipeline in the GOM. The seminar identified future research areas.

To conduct a one day seminar at MMS Herndon to review work relative to Mexico's risk based technology developments, especially on facilities in the Bay of Campeche and to discuss possible areas of future cooperation.

To conduct an in-house workshop for the MMS to review the state of the art of composite applications for the offshore oil and gas industry.

The purpose of this project is to construct a data set that integrates all relevant data on individual component reliability of polyester moorings. This will achieve an accurate rational for collecting future data with the most information value. It will also compare a polyester mooring design with a standard steel design. Since the future of deepwater Gulf of Mexico will undoubtedly consist of floating production, it is vital that the MMS develop a rational of comparison between polyester verse steel mooring systems.

The objective of this project is to develop a guideline on the use of fibre ropes for moorings of floating offshore oil and gas facilities. The design guidelines will provide the necessary overview of the issues and identify the areas of design and specifications that should be included in the mooring design.

This project will continue development of the earthquake Load and Resistance Factor Design (LRFD) guidelines for offshore structures. The focus is on three topics: 1) concrete Gravity Base Structures, 2) seismic hazard characterizations, and 3) verifying of the proposed ISO guidelines. The unique characteristics of concrete gravity based platforms will be addressed, including seismic loading considerations and soil-structure interaction. The results of selected seismic hazard studies will be reviewed to determine the accuracy of the guidelines for specifying the design spectrum.

The workshop is designed to define the state of the art of corrosion protection of marine structures and pipelines, to define the state of the art of testing for corrosion damage, to identify the technical and non-technical barriers which hinders a fuller utilization of advanced methods for mitigating corrosion on marine structures and pipelines, and to identify research and development projects that would advanced corrosion mitigation technologies. Marine structure is defined as offshore structures, harbor structures and ship structures.

This JIP conducted large scale model tests on different configurations of HCR risers. While there were already several riser analysis software programs available to industry that address the computational requirements needed for HCR analysis, there was little model or full scale test data that validates these programs. Phase II included some additional evaluation of the test results and was funded by other entities.

This JIP was formed to investigate the recent increase in early vibration fatigue failures to welded connections in thin-walled piping on offshore installations. The project included data collection, fatigue testing, and formulation of design guidelines. Current design procedures for offshore piping considered static stress levels, and sometimes, low frequency resonance modes. New materials used in piping made these design criteria obsolete. Increasingly, thin walled piping, made of new materials such as duplex* or stainless steels, was being installed offshore.

This is a Joint Industry Project (JIP) to establish a guideline for engineers using non-linear analysis methods in documentation of ultimate limit states for offshore structures. This will be done by establishing procedures suitable for the practicing engineer; showing that non-linear analysis methods will give reliable predictions of ultimate capacity fore offshore structures; establishing requirements of the non-linear analysis software. The guideline will cover all aspects from the requirements of software through modeling if loads and geometry to reporting of details.