State the term - constant eccentricity
A pre-stressed concrete beam has a width of 300 mm and an overall depth of 450 mm. The permissible stresses in tension and compression due to pre-stressing alone are 5 N/mm2 and 30 N/mm2, respectively. Find the required pre-stressing force in the tendon and the eccentricity of the tendon, if a straight tendon with a constant eccentricity is to be provided in the beam.