A kind of combined hollow building 
plank with reinforcing 
steel bar in it, comprises the prefabricate lamella, the mould 
hull, the hidden rib, the upper 
plank, the mould 
hull fixed on the prefabricate lamella, setting the hidden ribbetween prefabricate lamella and the mould 
hull, and close together to them, overlaying the upper 
plank on the mould hull, and connect with the hidden rib for the integral whole, its characteristic lie in setting reinforcing rib 
vein on the prefabricate lamella. Thus, the strength of the prefabricate lamella is high, the firm degree is big, it's not easy to come forth of craze, in the same time, the strengthening pole subject and spread the force of building plank in the mould hull, improved the 
mechanics function of the building plank consumedly, in addition, the building plank still has the character of structure is simple, the strength is high, the anti- transform, anti- vibrate the function is good, construction convenience etc.