The Portal Frame Based On Space Overall Reliability Analysis Of Ultimate Bearing

Current frame specification of portal type is the type of portal rigid frame structure simplified to the direction of the vertical and horizontal bearing load bearing two plane rigid frame system respectively and structure design, internal force calculation ignored the gantry frame integral structure as a space force system, the common frame through the longitudinal constraint and deformation coordination between components. So that a more reasonable design method is based on the global analysis as a whole on the basis of the ultimate bearing, and the type of portal frame structure overall reliability as the goal of the ultimate bearing state. This paper based on the ANSYS parameterized (APDL) command flow operation, the steel structure based on the space integral of the ultimate bearing reliability is analyzed.1. According to related specification and data by finite element software ANSYS is established considering the double nonlinear gantry frame space finite element analysis model. Ultimate bearing capacity of tracking analysis, find out the main failure modes and ultimate bearing capacity. Analysis shows that the type of door rigid frame structure system possible failure mode is overall ultimate bearing column symmetry instability, beam and column as a whole beam deflection and vertical migration. Mainly is the deformation of beam and column is too big lead to loss of portal rigid frame structure system overall bearing capacity.2. Overall failure mode based on the type of portal rigid frame structure system, set up the structure of the bearing capacity limit state functions and the related influence factors sensitivity analysis. Analysis shows that affects gantry frame space as a whole the main factors of ultimate bearing reliability is a frame under horizontal load and vertical load, span rigid frame, material yield strength as well as the section size of beam and column. 3. Solving the gantry frame structural system reliability analysis based on space overall limit load, comparing with component based on solving its ultimate bearing and reliability based on ultimate bearing plane whole. Analysis shows that the gantry frame for the reliability of solving underestimated the safety of structural system reliability level.