Impact of point load arising from installation and laying on local buckling of large diameter submarine pipeline

The large diameter pipelines, compared to conventional diameter pipelines, are more likely to cause local buckling instability in case of point load subjected during its installation of submarine pipelines. In the local buckling check on submarine pipelines, the correction method, though, has been given in DNVGL-ST-F101-2017 for point load, the protection of concrete counterweight layer on the pipeline has been ignored, the method is therefore considered to be incompatible with the actual structure of large diameter pipelines, and the calculation results are conservative. With finite element analysis method, the local buckling, which is resulted from point load in the installation process of large diameter submarine pipelines, was systematically studied with actual engineering pipeline structure taken into consideration during analysis. Engineering examples were provided to compare the calculation results from finite element method with those from the DNV standard, allowing supplement to the DNV standard in terms of analysis method. This is of good popularization value for local buckling design of large diameter submarine pipelines.