Increased problems associated with the production of gas from water depths greater than 200 feet prompted the investigation the adequacy of existing engineering data for prediction of the forces acting on unburied pipelines in these deeper water depths. Over 100 specific cases of pipeline or platform damage or movement due to hurricanes were analyzed to determine the principal reason for the damage. Limited overwater meteorological analysis existed; therefore, hurricane surface wind fields (as a function of time and distance) had to be developed from raw data such as obtained from aircraft reconnaissance,...
Increased problems associated with the production of gas from water depths greater than 200 feet prompted the investigation the adequacy of existing engineering data for prediction of the forces acting on unburied pipelines in these deeper water depths. Over 100 specific cases of pipeline or platform damage or movement due to hurricanes were analyzed to determine the principal reason for the damage. Limited overwater meteorological analysis existed; therefore, hurricane surface wind fields (as a function of time and distance) had to be developed from raw data such as obtained from aircraft reconnaissance, ship reports of wind, wave and swell, and land stations. Detailed analyses were made for these storms and correlations between these storms and the actual pipeline damage pattern they produced were accomplished. Pipeline risk criteria are dependent on the frequency of occurrence and the size, intensity, path and speed of advance of major storms. The significance of each of the storm variables is presented. Large, slowly moving storms cause considerably more pipeline damage than smaller more intense storms that move more quickly. This analysis has also made possible estimates of the lift and drag forces acting on pipelines on the sea floor. Bottom particle velocities and accelerations associated with these forces can be estimated from these data. Eight appendixes and a set of pertinent tables and functions are included to simplify the engineer's analysis work. Appendixes consist of (A) initial pipe settlement, (B) gravitational loading, (C) Airy wave theory, (D) Stoke's wave theory, (E) pipeline stability, (F) vortex shedding, (G) pipe span loading and (H) constructional loading.