The goal of this study is to assess cast iron pipes (CIPs) and present a residual
tensile strength prediction model using pit characteristics and fracture toughness. The
results is the followings. First, average pit depths of collected CIPs were in the
range from 0.63 to 6.49 mm, loss of tensile strength compared with net metallic tensile
strength were from -7.06 to 67.91 percent. Second, fracture toughness for NS-CR-1, NS-
CR-2, and NS(2)-CR-1 were in the range from 62.85 to 89.39 kgf/m㎡√mm,and average of
those samples was 73.69 kgf/m㎡√mm on CIPs. Third, the models developed in this study
by using pit characteristics and fracture toughness showed a little good correlation
for measured residual tensile strength, and the results will be expected to help for
water utilities to manage CIPs in the aspect of rehabilitation and assessment of
structural safety on CIPs
