We tested three types of bar in tensile test and direct shear test, so we have six bars of steel to test. In testing also including of error that come from any way such as long term of using of testing machine and error that come from tester such as wrong reading of value and miss of installing the sample.
From the value after we tested all of steel in two methods. We get that in tensile test yield strength of DB16 is the grestest follow by DB28, DB9 respectively. Elongation of all three steel bar is around 4%.
In the second method, direct shear method, T value of the double of all is about double to the single vale in kpc unit.