Importing a survey
From LimeSurvey Manual
Importing a survey structure is done by clicking the Create new survey button and selecting the Import tab:

To find out a more detailed explanation on how to do it via LimeSurvey, read the following wiki section on how to use the LimeSurvey import function.
If you do not want to use LimeSurvey to import a survey structure, access the following wiki page on alternatives to the LimeSurvey import function.