@prefix : <http://sample.org/ont#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@base <http://sample.org/ont#> .

<http://sample.org/ont#> rdf:type owl:Ontology .

:P rdf:type owl:DatatypeProperty ;
   rdfs:domain :A .

:A rdf:type owl:Class .

:B rdf:type owl:Class ;
   owl:equivalentClass [ rdf:type owl:Class ;
                         owl:intersectionOf ( :A
                                              [ rdf:type owl:Restriction ;
                                                owl:onProperty :P ;
                                                owl:hasValue "B"
                                              ]
                                            )
                       ] .

:b rdf:type :A , owl:NamedIndividual ;
   :P "B" .