Bottom Stability Analysis

Pipeline On Bottom Stability Analysis

Pipeline on bottom stability is an interaction of pipe, water and soil. The important factor that taken into account is the water flow whereby determining the magnitude and time variation of hydrodynamic drag and lift forces.

The second factor is soil. There have 3 friction will happened which are static, sliding and cohesive friction. So, it’s very important to understand the soil condition at the pipeline route area so that accuracy of analysis achieved.

These are some input provided for on bottom stability analysis :
1. Pipeline Data

Outside diameter 
Wall thickness
Density of Pipe
Corrosion Coating Thickness
Corrosion Coating Density
Concrete Coating Thickness
Concrete Coating Density
Field Joint Material Density
Concrete Coating Cutback
Corrosion Coating Cutback
Pipe Joint Length

2. Wave and Current Data 

Significant Wave Height (Hs)
Spectral Peak Period (Tp)
Wave Angle
Wave Spectrum Type
Water Depth 
Current Velocity
Current References Height from Bottom
Peakedness Parameter

3. Physical Parameter

Density of Content
Density of Seawater
Marine Growth Thickness
Soil Type
Mean Grain Size – DNV RP E305
Roughness – DNV RP E305
Undrained Shear Strength (Su) – DNV RP E305
Lift Coefficient – –DNV RP E305
Drag Coefficient – DNV RP E305
Inertial Coefficient – DNV RP E305

source:

http://ogapipeline.blogspot.com/2009/07/part-9-pipeline-on-bottom-stability.html