STATIC STRESSES IN THE MAST AND SUBSTRUCTURE IN A SYSTEM OF MAST-SUBSTRUCTURE-BASE-FOUNDATION

The mast and substructure of a drilling rig is studied in a system of mast-substructure-base-foundation system.Calculation of the Static stresses in the mast and substructure has been done with finite element method.The sink of the ground surface was calculated with both Winkler's model and limited compressibility model.Simplified treatment of all types of bases was proposed.Finally,a sample of systematic mast and substructure calculation was done with successive iteration.A special-purpose computer program for systematic analysis of mast and substructure was developed and practical calculation was compared with the results calculated with previous method.Valuable conclusions for design and research were given.