Semantic interoperability based on ontologies is nowadays becoming a great challenge. In a cooperation of shared knowledge sources, alignment of ontologies requires to discover mappings between semantically related entities of these different ontologies. This task is based on a similarity measures service: it relies on various mappings methods which are combined and refined to semi-automatically generate mappings between ontologies. We propose a computer-aided system to allow the expert to choice similarity measures on demand. We try to define a relevant proposal relating to the geotechnics domain and its various sub-domains.