# Interoperability Analyses of BIM Platforms for Construction Management
## 3 Results
### BIM Interoperability Through Gantt Charts--Management2 Design  
When working on a project, a planning engineer, a construction manager, or a consultant can share the schedules with designers or project owners. Additionally, this situation was studied, considering Gantt charts produced by CPM software and exported to design software. In particular, sample Gantt charts were produced by software packages like Microsoft Project (in both versions 2013 and 2016), Autodesk Navisworks, and Synchro Pro and imported into Trimble Tekla Structures in order to assess their interoperability and to evaluate the reverse side of the situation described in the previous subsection. As a first test, a simple Gantt chart was produced in Microsoft Project 2013, saved in XML format, and imported by Tekla Structures. The result showed that the XML exchange was performed with a very small error in the third task, named \"Second Floor\". The planned duration for this task was not read correctly, but since the task end dates were correctly transferred, this problem could be fixed with small adjustments (medium interoperability). An important note should be added here: the Gantt chart produced for this case did not contain many details and was not complicated, so the problem was easily detected. For complicated Gantt charts produced in MS Project 2013, other issues might show up throughout the procedure. With the same approach, Microsoft Project 2016 was tested. According to the results, it was shown that an XML file produced and saved in MS Project 2016 can be used without loss of data in Tekla Structures, so, in this case, exchanging files from MS Project 2016 to Tekla Structures could be effectively performed (good interoperability). In practice, exchange from Navisworks to Tekla Structures is also possible between various stakeholders through a workflow Gantt chart. For example, a Gantt chart that is produced in Navisworks can be imported to Tekla Structures with the purpose of reviewing, controlling, or managing assigned tasks. Therefore, a Gantt chart interoperability test from Navisworks to Tekla Structures was also performed. Since the previous tests presented for Gantt chart interoperability from Tekla Structures to Navisworks were satisfactory, the same Gantt chart was used for the reverse-way test, directly exporting it from Navisworks to Tekla Structures via XML format, although this kind of \"round-trip\" procedure is not recommended. After the import operation of the XML file produced in Navisworks into Tekla Structures, the Gantt chart output resulted in being aligned in terms of \"Task Name\" and \"Start Date\" fields (good interoperability) but \"Task Duration\" and \"End Date\" information were wrong (poor interoperability). The reason for this may be due to the lack of \"Task Duration\" in Navisworks, which can lead to incompatibilities between different BIM software packages. However, it was necessary to understand if the error was due to the \"round-trip\" procedure or to the incompatibility between the software packages; therefore, an additional investigation was performed. As done with the previous tests, a simple Gantt chart was prepared and exported as XML from Navisworks to Tekla Structures. The results were comparable with the previous test, leading us to think that the problem in Gantt chart interoperability may be due to an incompatibility between Navisworks and Tekla Structures. Finally, Synchro Pro was assessed exporting an XML Gantt Chart to Tekla Structures. Since the reverse exchange was shown to be correct, a \"round-trip\" case was evaluated. The result was