The author analyses some problems in pool design, such as the determine of groundwater level, the setting of shrinkage joint, practice of later casting zone and the fitting of design and construction.

Porous concrete will shrink, so it is necessary to deal with its shrinkage character firstly when studying the problems of joint location and reflection crack of porous concrete base.

In order to prevent the cracks that would be likely caused by restricted conditions of the wet-joint, the wet-joint demands using expansive concrete to compensate the shrinkage and creep.