# Interoperability Analyses of BIM Platforms for Construction Management
## 3 Results
### BIM Interoperability Through IFC Standard  
In this subsection, the assessment of the exchanged IFC model between Trimble Tekla Structures and ACCA Edificius, Autodesk Navisworks, Synchro Pro, ACCA usBIM.viewer+, and Graphisoft Solibri Model Checker is presented. The evaluation was performed by checking all the 16 repetitive elements and corresponding chosen parameters in the importing software. ACCA Edificius correctly imported all the names of the elements, identifying them in the description tab as IfcEntity \"Input Name\" (Dimensions). For example, for Element 1, its description was decoded as IfcSlab \"SLAB\" (300*2100). From this point of view, the information was properly transferred (overall, good interoperability). In terms of representation and geometrical properties, two elements showed defects. In Element 7, there were some missing details in the representation of the object: in fact, although the longitudinal rebars were correctly defined, stirrups in the mid-column were not included in the 3D representation. This problem can be easily spotted by a structural engineer. From the point of view of project management, the missing information might not create significant scheduling or planning errors in the tasks; however, for cost management, the information should be taken into account. In Element 14, the surface treatment was not properly represented in the importing software. Since these cannot be considered critical issues, the information \"Geometric Properties\" was evaluated as medium interoperability for these two elements, and good interoperability for the other ones. The Material Type field exchange was assessed as \"poor interoperability\" for all the elements. The imported material types were coded with numbers (semantic codes) that did not convey a direct understanding of the type of structural material. Of course, it is possible to backtrack the material type corresponding to each semantic code in order to identify the correct material; however, this would be a time-consuming task. From the project management point of view, the most significant interoperability issue was regarding the transfer of the field \"Phase\". The imported model does not provide the \"Phase\" information, which is embedded in the IFC Model. This means that if a project designer or owner uses Tekla Structures to include the time information inside the Tekla IFC model, it is not possible to transfer this information through IFC. If other disciplines choose to follow this approach, there might arise the necessity of using other BIM tools to obtain the phase information. The results of these tests are summarized in Table 1.  
Following the same criteria, the IFC model imported by Autodesk Navisworks was assessed. The results are summarized in Table 2. Generally, all the fields of all the elements were correctly imported (good interoperability), apart from some isolated cases. In Elements 7 and 14, some problems related to the stirrups of the column element and to the surface representation, respectively (medium interoperability), showed up. The phase information was lost for Elements 7, 10, 11, and 14. Consequently, the assessment was aimed at identifying if a 4D model can be transferred from Tekla Structures to Navisworks by use of the IFC standard. Except for the issues described above,  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c} \hline \hline
**Edificius** & & & & & & & & & & & & & & & & & & \\
**Element** & & & & & & & & & & & & & & & & & & \\ \hline Name & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) & \(\surd\) \\ Geometry & \(\surin general, a simple workflow between stakeholders may be accomplished without too much additional work after an IFC file exchange.