Assume straight line instead of parabola for stress-strain curve of concrete as given below and partial factor of safety as $$1.0.$$

A rectangular under-reinforced concrete section of $$300$$ $$mm$$ width and $$500$$ $$mm$$ effective depth is reinforced with $$3$$ bars of grade $$Fe$$-$$415,$$ each of $$16$$ $$mm$$ diameter. Concrete mix is $$M20.$$

The depth of the neutral axis obtained as per $$IS:$$ $$456$$-$$2000$$ differs from the depth of neutral axis obtained in $$Q.08$$ by

Assume straight line instead of parabola for stress-strain curve of concrete as given below and partial factor of safety as $$1.0.$$

A rectangular under-reinforced concrete section of $$300$$ $$mm$$ width and $$500$$ $$mm$$ effective depth is reinforced with $$3$$ bars of grade $$Fe$$-$$415,$$ each of $$16$$ $$mm$$ diameter. Concrete mix is $$M20.$$

The depth of the neutral axis from the compression fibre is

A continuous beam $$250\,mm \times 450\,mm$$ carries $$6$$ numbers of $$12$$ $$mm$$ diameter longitudinal bars as shown. The factored shear force at the point of inflection is $$200$$ $$kN.$$ Check if the beam is safe in bond. Assume $$M15$$ mix with $${\sigma _{ck}} = 15\,\,N/m{m^2}$$ and mild steel with $${\sigma _y} = 250\,N/m{m^2}.$$ A clear cover of $$25$$ $$mm$$ can be assumed. The design bond stress for mild steel bars in $$M15$$ concrete is specified to be $$1.0\,N/m{m^2}.$$

A simply supported rectangular prestressed concrete beam $$200$$ $$mm$$ wide and $$400$$ $$mm$$ deep has an effective span of $$12$$ $$m.$$ The prestressing cable has a triangular profile with zero eccentricity at ends and $$70$$ $$mm$$ at the midspan as shown in the figure below. The effective prestress is $$800$$ $$kN$$ after all losses. Determine the value of point load, the beam can support at the midspan if the pressure line passes through the upper kern of the section. The weight density of the material of the beam can be taken to be $$25$$ $$kN/{m^3}$$