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Recent content by RAYC1

  1. RAYC1

    Tension Member and Inactive Member used in same analysis

    This limitation was fixed in late 2009. The problem was that the same flag was used to denote that a member was inactive due to the INACTIVE command or inactive because a tension member went slack. So inactive members could become active inadvertently. Also after each tension/compression case...
  2. RAYC1

    Master-Slave Connection

    If solid elements are defining the slab, then: 3) Master & Slave directions must not connect to solid elements. Use plates instead. Use SLAVE FY, if vertical is the only direction controlled; then fix FY & MX & MZ at the master. Use thicker and/or stiffer plates within the pile zones.
  3. RAYC1

    Zero Stiffness Warning

    The SET PRINT 1 command's only purpose is to omit the message at the users request. It is not an error. It is rather more a note or FYI. Zero rows and zero columns (at a joint) in the global stiffness matrix can occur when trusses or releases or tension/compression-only are used by some or all...
  4. RAYC1

    Zero Stiffness Warning

    Add a SET PRINT 1 command before the Joint Coords by using the editor.
  5. RAYC1

    Advanced Analysis Engine

    A Buckling factor calculation procedure is included with the STAAD basic solver. This simple procedure calculates the Buckling Factor for any number of primary load cases. The analysis command is: PERFORM BUCKLING ANALYSIS MAXSTEPS 15 If you can, upgrade to the current Build 03 for StaadPro...
  6. RAYC1

    Master - Slave question

    All members and plates that are embedded in a rigid master/slave will have zero forces and moments; so they will naturally pass the code checking. Floor diaphragms modeled as SLAVE ZX will have embedded plates with zero inplane forces/stresses but will have bending moments and transverse...
  7. RAYC1

    Is it possible to assign Postprocessing values to Modeling mode?

    In the Post Processing mode, click on Results then Update Properties. Then File Save.
  8. RAYC1

    Different values for max Mx / My

    You are looking at the plate element center moment resultants table. The plate element centers are farther from the slab center and slab edge in the 4x4 model than in the 20x20 model. If you look at the corner stresses table, then the moments are 6.30 t-m/m in the 20x20 model and 4.49 in the...
  9. RAYC1

    Total Shear Force on a plate element in STAAD.Pro

    V=SQRT[ (SQX x Plate thickness x Plate width1)^2 + (SQY x Plate thickness x Plate width2)^2 ] would be the maximum principal shear force. In general, it would be at an angle to the plate edges. There is also the inplane shear to consider in some cases.
  10. RAYC1

    Buckling Analysis (Stardyne Engine)

    Joint or member loadings are all OK. For the inclined members, distributed loads can be in local or global directions. For better accuracy, the vertical and inclined members should be subdivided into 3 or more members each. Staad.Pro 2007 has 2 new buckling methods. The method that comes with...
  11. RAYC1

    Stress contours by center stress or nodes stress?

    The nodes stress is more reliable if you also uncheck index based on center stress. This will average the node stress from the plates that touch that node. You may want to limit the display to the plates in one plane rather than include wall and floor plates into one average. The node stress...
  12. RAYC1

    CODES FOR STAAD W SECTION

    You need a CHECK CODE ALL after the last PERFORM ANALYSIS to see the effect of the member selection after the analysis. You may want a STEEL TAKE OFF before the selection to compare with the after value. You may also want a second PRINT ANALYSIS RESULTS based on the selection. LOAD 2 LOADTYPE...
  13. RAYC1

    Corner stress vs Center stress, which one shall be used ?

    The center stress is the most reliable but you cannot ignore the corner stresses. In many cases the maximum stresses will be at the edges of a floor/wall/region. For the corner stresses you should average all of the corner stresses at a node because they will not be equal in each plate. In...
  14. RAYC1

    Simle plate problem

    You are looking at the element center stresses. The element corner stresses would be a better location for comparison. The STAAD element center stress resultant, in this case, is -.529 kN-m/m. The STAAD element stress resultant at the center of the edge is 1.147 kN-m/m. These results are...
  15. RAYC1

    Solver Performance

    Does the model have master/slave? This data can cause some slow down. I can give better comments if you email the STD file of the large models that are slow (ray@ca.reiusa.com).

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