Seismic Influence on Subsea Pipeline Stresses

Subsea Free Span Pipeline Damage Detection Based on Wavelet Transform under Environmental Load

During their service life, marine pipelines continually accumulate damage as a result of the action of various environmental forces. Clearly, the development of robust techniques for early damage detection is very important to avoid the possible occurrence of a disastrous structural failure. Most of vibration-based damage detection methods require the modal properties that are obtained from mea...

Halliburton sets new deepwater record with subsea pipeline testing device

Seismic Stability of Subsea Tunnels Subjected to Seepage

Strength reduction method and ADINA software are adopted to study the stability of submarine tunnel structures subjected to seepage and earthquake under different seawater depths and overlying rock strata thicknesses. First, the excess pore water pressure in the rock mass is eliminated through consolidation calculation. Second, dynamic time-history analysis is performed by inputting the seismic...

Improved FTA Methodology and Application to Subsea Pipeline Reliability Design

An innovative logic tree, Failure Expansion Tree (FET), is proposed in this paper, which improves on traditional Fault Tree Analysis (FTA). It describes a different thinking approach for risk factor identification and reliability risk assessment. By providing a more comprehensive and objective methodology, the rather subjective nature of FTA node discovery is significantly reduced and the resul...

Influence of Stresses on Precipitation

Precipitation, which usually occurs by nucleation, growth and coarsening, may be affected by elastic stresses which influence the thermodynan~ics of the system and thereby the driving force for precipitation. Such stresses may be internal, e.g. coherency stresses, or external, i.e. externally applied stresses. The consequences for nucleation, growth and coarsening are discussed in detail with s...