What are some literary devices used in Fences?

One of the literary devices in Fences is the symbolic use of fences. Troy wants to build a fence around his property, and the fence is both literal and figurative. The fence is intended to keep death at bay, and it also symbolizes the way in which Troy keeps people, including his sons, at an emotional distance from himself.
Another literary device is that death is personified in this play. Troy says that he has actually seen death when he had pneumonia, and death marched right up to him with his sickle. Troy claims that he threw death's sickle and wrestled with death for three days until they were both weak. Death then put on a white robe, like a Klansman, and marched off, promising to be back later. Therefore, death acquires the attributes of a person in this play. Troy also says, "Death ain’t nothing but a fastball on the outside corner." In this metaphor, death is likened to a kind of pitch that Troy, as a skilled baseball player, thinks he can defeat.

August Wilson makes notable use of metaphor in Fences. The most notable metaphor comes from the play's title itself. The action of the play revolves around a fence that Troy and his son Corey are building around Troy's yard. The fence represents both the metaphorical fences that Troy builds around himself to keep people from getting too close to him and the metaphorical fences that he faced in society preventing him, as a black man, from finding success as a baseball player. The meaning of the fence metaphor is most clear when Bono explains, "Some people build fences to keep people out and other people build fences to keep people in."
Troy frequently calls upon baseball imagery in the play, which takes on symbolic meaning. For instance, he describes death as a "fastball on the outside corner," and when explaining his extramarital affair, he says he wanted to "steal a second." Paired with the more explicit baseball imagery, the fence Troy is building itself parallels the traditional fence around a baseball field.
The play ends with the final and very important symbol of Raynell's garden. In the last scene of the play, Troy's daughter Raynell and wife, Rose, regard a garden that Raynell planted the night before, after Troy's funeral. Rose tells Raynell to give it time and the garden will grow. This symbol represents renewal, growth, and positive change for the family in their next chapter after Troy's death.