L51477 Theoretical and Experimental Investigation of Mud Forces on Pipe

Presents a mathematical model for predicting mud loading on offshore pipelines through a combination of experimental and theoretical studies. A dimensional analysis followed by three different sizes of drag box tests were conducted; the theory and test results are presented and compared.

Laboratory tests were made in a shear box using a small scale deeply buried vertical pile model to check test procedures and provide a link between the present work and extensive previous data by Marti at Texas A & M University. Maximum drag factors for rigidly held deeply buried horizontal pipes in the shear box .rere then examined and shown to be the same as for the deeply buried vertical pile. Next, normal and axial drag factors for deeply buried horizontal pipes oriented oblique to the flow in the shear box were obtained as a function of cross-flow angle in pressurized soil. Additional tests were made in the shear box to obtain drag factors on both partially recessed and shallow completely buried pipes rigidly held normal to the flow in unpressurized soil.