The most common damage assessment technique for concrete structures is visual inspection (VI). Condition assessed by
VI is subjective in nature, meaning it depends on the experience, knowledge, expertise, measurement accuracy, mental
attention, and judgment of the inspector carrying out the assessment. In many post-event assessments, cracks data
including width and pattern provide the most indicative information about the health or damage state of the structure.
Residual cracks are sometimes the only available data for VI. However, due to adjacent elastic members, earthquake
displacement spectrum, or re-centering systems, these measurements may lead to erroneous decisions. To overcome this
problem, this paper proposes a novel damage index based upon Fractal Dimension (FD) analysis of residual cracks as a
complementary method for VI. FD can quantify crack patterns and enhance the routine inspection procedure by
establishing a crack pattern recognition system. This algorithm was validated through an experimental study on a large
scale reinforced concrete shear wall (RCSW). The results demonstrate the novel technique as a quite accurate estimator
for damage grades and stiffness loss of the wall.