In its broadest terms, the structure of As I Lay Dying revolves around the preparations for and the actual journey from the Bundren farm to a town forty miles away in order to bury Addie Bundren. During the journey, several difficulties are encountered. So, in one sense, the novel has a linear structure based upon the movement of the funeral procession traversing the forty miles from the Bundren farm to Jefferson. But the novel is also structured in such a way that the author has virtually removed himself from the story. He allows his characters to tell their own story. Accordingly, each of the fifty-nine sections is narrated by some character in the novel. Even though there are several important narrators who are not Bundrens, the largest number of the sections is presented by one or the other of the Bundrens.
By using a different narrator for each section, Faulkner accomplishes many things. First, he allows or forces the reader to participate in the story. Since Faulkner has removed himself from the story, that is, since he doesn't use a straight narrative technique to explain certain aspects, we must enter more directly into the story and determine for ourselves the exact nature of each relationship or the significance of any particular event.
Second, the technique allows us to know the inner thoughts of all the characters. We see into the mind of each character directly and must analyze what we find there. Faulkner, as author, has not told us anything about the characters — he has simply presented them and we must examine their inner thoughts and determine for ourselves what types of characters they are.
Third, we are able to see each event from multiple perspectives. For example, when the coffin is lost in the river, we have several narrations which allow us to see the same event from many different vantage points. Darl gives his narration of the loss of the coffin; from Vardaman, we hear of his mother being a fish swimming in the river; from Cash, we hear that the coffin wasn't on a balance; and from Anse, we hear that this is just one more burden we must endure before he can get his false teeth.
Therefore, with the multiple narration of each event, we see that event from many angles and observe what type of emphasis each character puts on that event; by this technique, we learn more about the character. Thus, in general, the structure of the novel allows us to become a part of the narration by drawing us more intimately into the novel.
But Faulkner has also included some narrators who are not Bundrens. These narrators help to bring a touch of objectivity to the novel. Without the outside narrators, we might become too involved in the unusual Bundren world. Faulkner is therefore careful to include outside narrators so as to remind us that the Bundrens are not typical people. For example, if the story were confined solely to the Bundrens, we might not realize that this dead body stinks so badly and that the Bundrens are violating all sense of decency by carting the body over the countryside. Thus, the outside narrators give us a touch of the real world by which we can measure our reactions to the Bundrens.
Therefore, if a central problem of the novel involved the reasons for Addie's request to be buried and why her family defy fire and water to fulfill it, then the structure of the novel forces the reader to solve these problems by analyzing each character.