Importare .r3d

Sargon/ CSE offers the ability to import models prepared in RISA3D©. However, as RISA3D uses "physical elements" which are not standard finite elements, Sargon/ CSE cannot also import and convert the results of the analysis carried out in RISA3D©. Physical elements in RISA3D, if detected, are automatically splint into proper finite elements.

The interface between Sargon, CSE and RISA3D can be implemented by asking Sargon or CSE to read a .R3D model provided in a given folder.

[.SOLUTION_PARAMETERS] "g" used to decide whether X, Y or Z axis is up. In Sargon/CSE Z is always up.

The model read from the R3D file will probably need addition of further information which it has not been possible to directly convert into Sargon/CSE environment. Models created by importing R3D files should be carefully reviewed in order to check that the conversion has worked successfully.

Some specific aspects of the main issues encountered when writing the conversion procedure are discussed in more detail below.

Before opening and reading the model which is to be imported, the conversion routine reads and imports the cross-sections in order to establish a suitable correspondence between the cross-sections in Sargon/CSE and those in RISA3D.

The mapping file between the CSE and RISA3D cross-sections is called "WSR_R3D_SHPCVT.TXT" and can be found in the CSE installation folder. This file should also be edited by the user in order to add new entries, when needed. This file will be used when a RISA3D model is imported into CSE. This file, known as the "mapping file", is usually the same for Sargon and CSE, and is structured as shown below.

The first column lists the names of the sections in the Sargon/CSE environment. The second column lists the corresponding section names in Sap2000. A section is identified by its name. If the name "beta" in Sap 2000 corresponds to the name "alpha" in Sargon/CSE, then the cross-section "alpha" will be mapped to "beta". To find out the properties of the cross-section "alpha", the program must open an archive of cross-sections of type .SMA (an .SMA file); in particular:

•if Sargon is in use, this will be the file "sargon.sma" in the Sargon program folder;

If the first line of the mapping file contains a "$" or "\\" symbol that means it is a comment line.

The first 18 characters of the names are used for matching purposes. For two names to be matched, each of these 18 characters must be identical.

1-The cross-sections in the .SMA file relevant to the program in use (Sargon or CSE) are read.

3-The cross-sections in the RISA3D model are read and then transformed into Sargon/CSE-type sections following the procedure below.

a- If a conversion is found between the name of the cross-section used in RISA3D model, and one entry of the second column of the mapping file, then the Sargon/CSE cross section in the first column of the proper row of the mapping file will be used.

b- If a conversion is not found and the cross section is of the types ("b" shape type in [SHAPES-LIST]): 1 (rolled I or H); 2 (rectangular hollow section, or tube); 3 (pipe); 4 (parallel flange channel); 5 (Tee rolled cross-section); 6 (double L cross section); 7 (angle); 8 (rectangular cross section); 9 (solid round); 200 (cold formed C); 201 (lipped cold formed C); 202 or 203 (Z cold formed); 251 (pipe); 252 (L cold formed); then the user will be prompted with a specific dialog in order to enter the dimensions of the cross section.

c- If a conversion is not found and the cross section does not belong to any of the previously listed cross-section types, then a dummy rectangular cross section is considered. The user may avoid such unwanted behavior by: i) adding the needed cross section to the Sargon/CSE database by using Samba, if this cross section is not available; ii) adding a new row to the mapping file with the Sargon/CSE archive cross-section name in the first column, and the RISA3D cross-section name in the second column. Otherwise, to save time, cross-section assignment may be re-done in the Sargon/CSE environment.

The conversion file is easy to manage and the user can add any lines they require.

It is as well to note that any user can always ensure that a cross-section in RISA3D is converted correctly to a cross-section in Sargon/ CSE, simply checking that the desired cross-section is in the .SMA archive and that the Sargon/CSE-RISA3D mapping between the names of the two sections is available in the mapping file. Once carried out, the work will of course apply every time those sections, special or otherwise, are used in any model in the future.

When installing upgrades, in order to avoid overwriting your mapping files and SMA archives, it is advisable to take a backup copy of both the mapping file and the SMA file.

Wood material is read with dummy values: it may later be modified according to real needs in Sargon/CSE environment. As not all the needed information is printed in R3D file (for instance yield stress and ultimate stress is not written for all materials), material data should be carefully revised once the file has been imported.

•Member point loads (member only), both forces and couples, both local and global reference.

•Distributed loads (temperature, forces or couples) on members, in the global or local reference system, also projected.

Basic load cases are read into Sargon/CSE as they are defined in RISA3D. If a load case has gravity multipliers these will be correctly read and the relevant individual loads will be applied to elements in Sargon/CSE. The following mapping between load types has been set up:

RISA3D (load category "h" in [BASIC_LOAD_CASES])	Sargon/CSE
0	LIVE
1	DEAD
2	LIVE
3	EARTHQUAKE
4	WIND
5	SNOW
6	LIVE
7	LIVE
other	LIVE

As results are not read from RISA3D no combination information is presently converted.

Not all the elements defined in RISA3D can be imported into Sargon/ CSE. The following element data are not imported:

It is assumed that relevant walls are modeled via plate elements, while footings will later be modeled in CSE by using constraint blocks.

MEMBERS are read with end releases and axial offsets. No member design parameter, or member supplemental data is read, as it is not used as such in Sargon/CSE programs.

Within Sargon/CSE, the connection code is used to indicate members which, although statically continuous with the node, must be considered as interrupted from a constructional point of view. Frame elements possessing any kind of end-release are automatically considered interrupted, hence there is no need for any connection code. There is, however, the problem of those elements which, despite having no end-release, must still be considered interrupted for the purposes of finding the equal jnodes and renodes in CSE. As there is no coding for this information in RISA3D, connection codes will have to be applied in Sargon/CSE environment before the jnode search is asked for.

The results of the analysis carried out in RISA3D are currently not available in CSE/Sargon, as:

1.Physical elements in RISA3D cannot be mapped into finite elements in Sargon / CSE. No proper nodal connection between physical elements and secondary elements is available in RISA3D.

2.No output file with known format is available with the internal forces computed by RISA3D. However, such internal forces, may easily be got by pasting tables from EXCEL into CSE, when needed, or by using special tools to define load levels acting to detach slave members from the master, in CSE.