As per Indian standard code of practice for prestressed concrete $$(IS:1343-1980)$$ the minimum grades of concrete to be used for post-tensioned and pre-tensioned structural elements are respectively

A concrete beam of rectangular cross section of $$200\,\,mm \times 400\,\,mm$$ is pre-stressed with a force $$400$$ $$kN$$ at eccentricity $$100$$ $$mm.$$ the maximum compressive stress in the concrete is

A fillet-welded joint of $$6$$ $$mm$$ size is shown in the figure. The welded surfaces meet at $$60$$ - $$90$$ degree and permissible stress in the fillet weld is $$108$$ $$MPa.$$ The safe load that can be transmitted by the joint is

The permissible stress in axial tension in steel member on the net effective area of the section shall not exceed the following value ($${{f_y}}$$ is the yield stress)