In the design of beams for the limit state of collapse in flexure as per $$IS:$$ $$456$$ - $$2000,$$ let the maximum strain in concrete be limited to $$0.0025$$ (in place of $$0.0035$$). For this situation, consider a rectangular beam section with breadth as $$250$$ $$mm,$$ effective depth as $$350$$ $$mm,$$ area of tension steel as $$1500\,\,m{m^2},$$ and characteristic strengths of concrete and steel as $$30$$ $$MPa$$ and $$250$$ $$MPa$$ respectively.

At the limiting state of collapse in flexure, the force acting on the compression zone of the section is

Consider the following statements:

$$1.\,\,\,\,\,\,$$ The width-to-thickness ratio limitations on the plate elements under
$$\,\,\,\,\,\,\,\,\,\,\,$$ compression in steel members are imposed by $$IS:$$ $$800$$ - $$1984$$ in order to avoid
$$\,\,\,\,\,\,\,\,\,\,\,$$ fabrication difficulties.
$$2.\,\,\,\,\,\,$$ In a doubly reinforced concrete beam, the strain in compressive reinforcement is
$$\,\,\,\,\,\,\,\,\,\,\,$$ higher than the strain in the adjoining concrete.
$$3.\,\,\,\,\,\,$$ If a cantilever $${\rm I}$$-section supports slab construction all along its length with
$$\,\,\,\,\,\,\,\,\,\,\,$$ sufficient friction between them, the permissible bending stress in compression
$$\,\,\,\,\,\,\,\,\,\,\,$$ will be the same as that in tension.

The TRUE statements are

In the design of beams for the limit state of collapse in flexure as per $$IS:$$ $$456$$ - $$2000,$$ let the maximum strain in concrete be limited to $$0.0025$$ (in place of $$0.0035$$). For this situation, consider a rectangular beam section with breadth as $$250$$ $$mm,$$ effective depth as $$350$$ $$mm,$$ area of tension steel as $$1500\,\,m{m^2},$$ and characteristic strengths of concrete and steel as $$30$$ $$MPa$$ and $$250$$ $$MPa$$ respectively.

The depth of neutral axis for the balanced failure is

Maximum strains in an extreme fibre in concrete and in the tension reinforcement (Fe-$$415$$ grade and $${E_s} = 200\,\,kN/m{m^2}$$) in a balanced section at limit state of flexure are respectively