DANCE

Choreographer Twyla Tharp will join American Ballet Theatre as artistic associate beginning Aug. 22 (the opening of the 1988-’89 rehearsal period). Tharp, 46, has previously been associated with ABT in creating the ballets “Push Come to Shove,” “The Little Ballet,” “Sinatra Suite” and “Bach Partita.” Tharp will choreograph a new work for ABT next season and will set several previously created pieces on the company over the next two years. Several dancers from her own company (seen in Los Angeles last April) will also be joining American Ballet Theatre shortly. Originally an avant-garde post-modern artist, Tharp is the first choreographer of her generation to create works for all three major American ballet companies: ABT, New York City Ballet and the Joffrey Ballet.