Seepage always eventuates through the foundation of all dams. The flow of water through the dam body generate seepage forces and endanger the dam stability due to piping. Controlling seepage after construction is quite difficult and an expensive job, hence proper practices should be adopted for seepage remediation in the designing stage. In order to investigate the more effective techniques among downstream (D/S) sand filter with upstream (U/S) clay blanket and cutoff wall, the Baz Ali small dam was analyzed using finite element approach SEEP/W 2D. The seepage behaviour through the dam was intuited by employing 1 m thick clay blankets on the upstream side with extending lengths of 50 m, 100 m, 150 m, 200 m, 250 m and 300 m. Furthermore, 5 m, 7.5 m and 10 m deep cut-off walls having 0.5 m and 1 m thickness were embedded for seepage mitigation. The seepage values obtained from SEEP/W 2D models were compared with each other. The SEEP/W 2D results and cost analysis show that clay blanket is more effective and an economical technique than a cut-off wall for tackling seepage issue. Hence, an upstream blanket of 100 m length is more efficient to diminish the seepage up to 58.65% in contrast to the base case without the remedial system.

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Eddy current thermography (ECT) employs the combination of conventional and advanced nondestructive testing (NDT) technique. This technology is capable to detect defect in subsurface of carbon steel welded sample of dimension 200 × 150 × 20 mm. The optimum joule heating process via eddy current distribution is 300A with the heat diffusion around 50-500 kHz (which is relatively high-frequency electromagnetic wave). Along with the emerging development of eddy current thermography, the infrared camera permits its radiation range to visualize the real-time image of the defect via the application of the thermoimager TIM software. The quantitative information about the defect will be acquired by the camera which is sensitive to the transient signal of heat through material under inspection. The analysis due to the geometrical shape, position, and length of lack of fusion (LOF) defect can be made through maximum amplitude temperature analysis. The investigation performs the temperature linescan graph of temperature amplitude via Matlab. The result obtained from ECT is compared to the error bar analysis in line with radiography technique. The studies demonstrate the effectiveness and reliability of the technique for the quantification analysis of lack of fusion (LOF) defect of welded sample.