Business Process Management (BPM) is a topic with growing relevance for businesses as well as public organisations. Until today, the analysis part of a BPM cycle is mostly done manually. Process modelling methods are not designed to allow for automated analysis. Our aim is to show that meaningful weakness patterns that support semi-automatic analysis of business process diagrams (BPD) can be defined when a semantically enhanced modelling method is used. We derive exemplary weakness patterns by analysing literature and interviews from a business process redesign project. These are applied to a set of process models, in which occurrences of these weaknesses are being searched automatically. A comparison of achieved and expected results indicates that our approach helps to identify weaknesses within the processes and therefore supports business process analysis endeavours.