Constructive system comprising at least four modular elongated prefabricated floor elements, each floor element defining a longitudinal axis parallel to its long side and a transversal axis parallel to its short side, and being arranged coplanar in a 2×2 matrix configuration such that each floor element is adjacent to another element by one of its long sides and adjacent to another of the elements by one of its short sides, the ends of the short sides of the floor elements resting on linear supporting elements, the floor elements comprising in the vertical face of each of the long sides a longitudinal groove having the direction of the longitudinal axis such that a cavity is formed between each pair of adjacent floor elements, the cavities being filled with a grouting, the system including at least one duct extending continuously along the two cavities and a post-tensioned tendon within the duct.
