Abstract: The dynamic displacement ductility and ultimate load-carrying capability of three partially-prestressed concrete (PPC) beams which were unbonded, were experimentally obtained by applying impact load to their middle with dropping hammers, and the typical measurement wave curves were given. Influences of a dropping hammers gravitational potential energy on the dynamic properties of the PPC beam were analyzed. Based on the analog simulation theory, the impact-load-carrying capability of the real unbonded PPC beam with span 12 m was gained. Results show that the unbonded PPC beams anti-impact properties are good, the fragile destruction will not happen, and the unbonded PPC beams can be used in wide-span underground structures.