Multiple web applications Vs all in one application

We have multiple (internal for company) ASP.NET applications like Enquery Management, HR Management, Reporting etc. hosted on cloud. All the applications share the same database. It is very difficult to maintain all these applications if any database schema level change happen. But from scalability perspective it is good to have seperate application (i.e. SOA).

So, my question is, which approach is good from mentainance and scalability perspective?

All those applications are for internal use so trafic is very low.

Thanks!