During the erection of steel hall
some of the purlins were mounted
improperly. 12 meters long truss purlins
have
been assembled inversely causing over 11º deflection of the truss from the
vertical plane. Defect was found after four years of use but ignored after
consultation with designer. Developing roof unseal forced present user to
consider its modernization. Because of expected weight growth of the roofing
layers new load capacity analysis was done by the authors of this paper. For
the
improperly mounted purlins it was shown that the loads exceeded the local
capacity over 3 tomes. For the sake of no user agreement for new mounting of
complete purlins,
strengthening by side straps frictionally fixed to the top
flange of purlin with high tensile bearing-type bolt was proposed.