A prestressed concrete rectangular beam of size $$300\,\,mm \times 900\,\,mm$$ is prestressed with an intial prestressing force of $$700$$ $$kN$$ at an eccentricity of $$350$$ $$mm$$ at midspan. Stress at top due to prestress alone, in $$N/m{m^2}$$ is

Factor of safety adopted by IS: 800-1984 while arriving at the permissible stress in axial compression is

Maximum size of a fillet weld for a plate of square edge is

A compound steel column consisting of $$2$$ $$ISHB$$ $$400$$ placed at $$320$$ $$mm$$ centers, carries a total axial load of $$2500$$ $$kN.$$ Minimum slenderness ratio of the compound column is $$30.$$ Width of the flange of one $$ISHB$$ section is $$250$$ $$mm$$ and its minimum radius of gyration is $$51.6$$ $$mm$$. Design a suitable single flat lacing. $$20$$ $$mm$$ diameter single rivet is used to connect the lacings to the column. Rivet capacity need not be calculated. The following table may be used.