Shape optimisation of singly-symmetric cold-formed steel purlins

This paper presents the results of a study aiming at shape optimising singly-symmetric cold-formed steel purlins. The “self-shape” optimisation algorithm previously developed, proven to be robust and converge known solutions is used for this purpose. Eight cases are considered, consisting 1.5 mm 1.9 thick purlins, spanning either 3000 or 8000 drawn with 4, 6 8 elements per half cross-section. aim minimise cross-sectional area subjected following constraints: (i) sections must least match second moment area, inward outward bending capacities commercial purlins as reference profiles, (ii) readily manufacturable using existing roll-forming process, (iii) can connected similarly by offering vertical horizontal flat long enough strategically positioned bolt gusset plates screw roof them, respectively, (iv) have an opening wide run services. restraints provided sheeting considered in when calculating capacities. Results show that converges consistent satisfactory satisfies all constraints, resulting useable When compared optimised result saving up 6.6% steel. cost material quite significant mass-produced product such efficiency relative were further validated FE analysis. analyses confirm superior section. may therefore benefit industry they represent more economical without compromising on usability performance products. However, model shows not expected experimental testing fully validate sections.