Earthquakes constitute a major problem for mankind resulting in loss of lives and structures. Though, Nigeria is not situated where major seismic activities are observed in the world, the country has experienced pockets of tremors comprising magnitudes ranging from 4.3 to 4.5. Smart structural materials suppress the structural vibration in a structure by adjusting the dynamic performance of the structure. One of such materials is the Shape Memory Alloy (SMA). SMA rods are unique for their shape memory effect and superelasticity and have been used as structural reinforcement for earthquake retrofits. This book focused on investigating the appropriate percentage of shape memory alloy and steel reinforcements for the least deflection in the column-capping beam of a 3-span composite bridge subjected to seismic load using finite element method with the aid of SAP2000 software. Five different earthquake scenarios (including Newhall Accelerogram) were used to obtain the best combination of steel and SMA reinforcement in the columns and capping beam for the best resistance to the Earthquake response.