The precast PC planks employed as embedded forms have come into practical use to improve the construction works of concrete slab. This method has many advantages such as being able to construct the slab in safety without scaffolding, shortning the construction period, etc., The authors fabricated composite beams as well as slabs with the precast PC planks and carried out static and cyclic loading tests. The composite slab was much superior in mechanical characteristics to RC slab and behaved as PC members. Consequently, it is concluded that this composite slab should be designed as PC member rather than RC one.
As a result of the test construction in situ, it has been made clear that this method is more practical and economical.