Abstract.A condition assessment of reinforced concrete building structures can be conducted accurately when the components of the building structure data are available. Otherwise, data must be developed through testing directly in the field. Non-Destructive Test method (NDT) was considered to avoid disruptions to the existing building structures. This study aims to develop a model for interpreting the residual strength of concrete structures in the field. Nine cylinder specimens with a diameter of 150 mm and a height of 300 mm and 27 cube specimens of 200x200x200 mm were prepared. Nine reinforced concrete beam specimens of 100x150x1100 mm were also prepared to represent a component of the reinforced concrete structure. Hammer and UPV apparatuses were applied to the cylinder and cube specimens considered. Results concluded that the value of the pulse velocity is directly proportional to the load and inversely proportional to the residual strength. The concrete structure with a residual strength of more than 60% is considered healthy or a structural in "good" condition. The concrete structure is also healthy when the v measured gives a value of 3.5 and above. This value is acceptable as it lies within the range v given in the reference of 3.5 to 4.5.