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Welding procedure of clad steel including deposition of carbon steel on nickel base alloy usually gives unaccepted mechanical properties. Cracks were formed along type II boundary in nickel base alloy pass and a martensitic layer was formed in carbon steel pass. In this paper, cracks along type II boundary were prevented by lowering the martensitic start temperature (TMs) of the martensitic layer. Decreasing of TMs was obtained by two methods: Dilution method and Grain refining method. Three levels of TMs (approximately 350, 200, and 50⁰C) are obtained. The results showed that: cracks along type II boundary were prevented at TMs lower than 200⁰C; however type II boundary itself was prevented at TMs lower than 50𠜌. Also post weld heat treatment was necessary to achieve accepted impact properties.

Uniaxial tensile and/or pull-out tests are performed to obtain the stress-strain curve of geogrids. The clamp lining in contact with a specimen in the uniaxial tensile test or the grit of a sandpaper clamp liner in a pull-out test affects the results. In this study, one geogrid made of polyester and another one made of high-density polyethylene (HDPE) are tested in the uniaxial tensile test using various clamps and in pull-out test using sandpapers of different grits. Based on the results obtained, it is recommended to test HDPE in uniaxial tests with serrated steel-lined clamps and in pull-out tests with sandpaper (grit 180) lined clamps. A polyester geogrid shall be tested in uniaxial tests with plastic-lined clamps and in pull-out tests with sandpaper (grit 400) lined clamps.