77. BOWLUS, F., LUDWIG, H. F., and MELBERG, L., "PuU-out Metliod Cuts Costs in 

 Placing Oregon Outfall Sewer," Western Construction, Mar. 1964. 



Keywords: Oregon, Outfall pipeline 



The construction metliod used to lay a 35-inch-diameter ocean outfall in Oregon is 

 described. The pipeline was welded and coated onshore and pulled out by a large ship 

 anchored offshore. The same ship was also used to excavate a trench through a sandbar for 

 tlie pipe. 



78. BRANDO, P., and SEBASTIANI, G., "Determination of Elastic Curves and Stresses to 



be Expected During Laying Operations," Offshore Technology Conference, Vol. I, Apr. 



1971, pp. I279-I292. 



Keywords: Stresses, Submarine pipeline 



Paper describes a finite element method for determination of sea line elastic curves and 

 stresses on a submarine pipehne during laying operations from a lay barge. The calculation 

 procedure considers both tension apphed at the lay barge and no tension applied. The 

 method can also be used for pipelines laid on sloping bottoms and in tlie presence of side 

 currents. The steps of the calculation procedure are described, and the results of the analysis 

 are presented in terms of dimensionless parameters. Dimensionless graphs witli tension, 

 deformation angle, bending movement, shear, and deflection data illustrate tlie complete 

 elastic curve over a large range of values of the pipe weight, stiffness, and bottom tension. 

 The results of tlie analysis are compared with other theories, and an example is given to 

 illustrate the computation procedure with the dimensionless graphs. 



79. BRATER, E. F., and WALLACE, R., "Wave Forces on Submerged Kpe Lines," 

 Proceedings of the 13th International Conference on Coastal Engineering, Vol. Ill, July 



1972, pp. 1703-1722. 



Keywords: Submerged pipeline. Wave-induced forces 



Paper presents the results of a laboratory investigation of the horizontal wave-induced 

 forces on a submerged pipeline. The total horizontal wave force on the submerged pipe is 

 assumed to be composed of two parts— a drag force due to the orbital velocities, and an 

 inertial force due to the orbital accelerations. Values of the horizontal components of the 

 orbital velocities and accelerations were calculated using the airy theory, and the values of 

 the coefficients of drag and mass were determined from tlie force data of the model 

 pipeline. The tests were run for a pipe suspended at various elevations above the bottom, 

 including very close to the bottom and in a trench. The coefficient of mass appears to have 

 the largest values for a pipe located near the bottom, and lowest values for a pipe located in 

 a trench. The coefficient of drag appears to decrease with an increase in Reynolds number. 



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