Sand Lake Shoppes Family Limited Partnership v. Sand Lake Courtyards, L.C., ET AL, 816 So. 2d 143 (Fla. 5th DCA 2002), says;
"The question is not whether Shoppes has been entirely deprived of ingress and egress, but, rather, whether or not there has been any interference of its right to free passage over the easement to the degree and amount originally contemplated by the parties." Shoppes, supra.
Although obviously a Florida case, easements generally are established by common law, or by statutory construction; then recorded in the official records in the county where the property is located; and that agreement cannot be dissolved or ammended without the stipulation or subsequent agreement of both the dominant and servient easement owners. In other words, no unilateral actions can be taken by either easement owner.
It would be my guess, that Georgia may well have similar case law that controls in your situation. If not, there is overwhelming abundance of the above type case law in Florida for guidance. This is by no means the only one that there is. More to your point, Shoppes directly cites to Diefenderfer v. Forest Park Springs, 599 So. 2d 1309 (Fla. 5th DCA), review denied, 613 So. 2d 4 (Fla. 1992), where Diefenderfer had a 50 foot wide recorded easement of which he had use of just 12 feet, as a result of a wall having been erected by the servient easement owner. Read Diefenderfer, for even more details.
In Florida, the action in court is to;
1. Pettition for and obtain first, a Temporary Injunction : (Enjoining your neighbor from further acts until the court settles the dispute).
2. Pettition for and obtain an Injunction: (Enjoining your neighbor from doing anything further during the course of litigation).
3. Pettition for and obtain a Permanent Injunction: (Enjoining your neighbor from doing anything further in the future).
4. Pettition for and obtain a Mandatory Injunction: (A direct order of the court to remove any obstructions and/or encroachments by a specified time, and prohibiting any similar such acts in the future).
An action in Mandamus, has been found to have no jurisdiction, insofar as Mandamus is a one-time only command and/or remedy.