Mark Evernden
March 4, 2013

Question 13

Posted in: Beams, Prestress

Something for all my Bridge Engineering students.

Pre-stressing a simply supported beam

week13

For the simply supported pre-stressed beam shown above, calculate the maximum allowable  length (in meters) if the maximum tensile stresses due to the unfactored dead weight are limited to 1N/mm2.

Take the density of concrete to be 24kN/m3 and the centroidal  axis is at mid-height of the section.Please ignore any reliving effects or the action of live loads

hint1-prestress

Hopefully you got an  answer of 36.7m, which is less than the transportable limit of 40m. If you got anything  other than 36.7m please read the solution. week13 solution

Posted in: Beams, Prestress

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