This should do the trick:
DECLARE @test-2 TABLE (
D int,
HT int,
Adresse1 char(2),
Adresse2 char(2)
)
INSERT INTO @test-2 VALUES (1,1,'AD','DS')
INSERT INTO @test-2 VALUES (1,2,'BS','HG')
INSERT INTO @test-2 VALUES (1,3,'XD','JH')
SELECT address
FROM @test-2 AS T
UNPIVOT (address FOR addresses IN (Adresse1,Adresse2)) AS U
Hope this helps
Gianluca