For no tension at any point in a gravity dam the criterion satisfied is:
1
The resultant of all the forces must always pass through the mid point of the base of the dam
2
The resultant of all the forces must always pass through the d/s extremity of the middle third of the base
3
The resultant force for all conditions of loading must pass through the middle third of the base
4
The resultant of all the forces must always pass through the upstream extremity of the middle third of the base