I added a couple additional tags to your question, so that a broader group of lawyers will see it. Your question goes more to eminent domain and the like than to constuction law.
Generally, no compensation is owed for blocking access if some access is still available. If any land was acquired, you could have been compensated for the land taking, and possibly for damages to the remainder.
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You should consult with a local attorney, and they can tell you if you have grounds for inverse condemnation or another claim due to your loss of business. In addition, a good local attorney may also be able to help you negotiate better access or business exposure than has been provided by the construction company.
It appears that the short answer to the question of whether you have a case here is "No."
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