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DESIGN COMPARISONS

FOR CASE STUDIES USING

SAP2000

SAFE NODAL METHOD

AND SAFE INTERNAL METHOD (WOOD -ARMER)

FOR THIN AND THICK PLATES

Jan. 2008

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TABLE OF CONTENTS

I REPORT SCOPE .................................................................................................................... 2

II THICK PLATE EXAMPLE ................................................................................................. 3

II -1- MODEL DESCRIPTION ................................................................................................... 3

II -2- MOMENTS IN X DIRECTION ......................................................................................... 4

II -3- MOMENTS IN Y DIRECTION ....................................................................................... 12

III THIN PLATE EXAMPLE ................................................................................................. 20

III -1- MODEL DESCRIPTION ................................................................................................ 20

III -2- MOMENTS IN X DIRECTION ..................................................................................... 21

III -3- MOMENTS IN Y DIRECTION ..................................................................................... 26

IV CONCLUSION ................................................................................................................... 30

APPENDIX A .............................................................................................................................. 31

APPENDIX B ............................................................................................................................... 32

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I REPORT SCOPE

We have been lately notifying unjustified reinforcement when using SAFE models for raft

foundations supported on soil. This situation was mainly detected in case of irregular geometry

of models, unsymmetrical grids of columns, shear walls near the edge of the raft,

The above CSI Technical Support and we were

advised to use the internal method (Wood-Armer) along with thick plate analysis in case of point

loads (Raf refer to Appendix B).

In what follows, two shell examples (raft foundation and suspended slab) will be the subject of a

study to compare between the analysis made by SAP2000 and the analysis made by SAFE using

both the nodal method and the internal method (Wood-Armer). The results of this study will be

adopted as a base for all horizontal shell designs.

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II THICK PLATE EXAMPLE

II -1- MODEL DESCRIPTION

For this example, a raft foundation on soil, supporting two corewalls near the edge and

rectangular grids of walls and columns, was modeled as a thick plate on SAP2000 and on SAFE

V8.0.8.

Fig. 1: Raft Model Geometry on SAFE