When configuring SQL analysis server type did you select? Multidimensional, Tabular or PowerPivot.
The default is Tabular, but during installing of SQL analysis, you should have selected Multidimensional, which is OLAP.
https://docs.microsoft.com/en-us/project/configure-sql-server-and-analysis-services-in-project-server-2013 documentation indicates this as well.
Michael Wharton, Project MVP, MBA, PMP and a Great Guy <br/> Website http://www.WhartonComputer.com <br/> Blog http://MyProjectExpert.com contains my field notes and SQL queries