Numerical investigation on roof truss with cold-formed steel sections

The needs of environmental conservation and economical development have forced Malay- sia's construction industry to use cold-formed steel roof truss as a replacement for traditional timber roof truss system. Compared to timber, cold-formed steel sections serve as a better choice in sustainable de- sign with several advantages e.g. reduce cutting down of trees, speedy in construction, stronger, lighter and flexible in erection. However stability issues occurred when using thin-walled cold-formed steel member for wide span roof truss. This paper presents the 7.8-metre plane truss and 25-metre truss by us- ing the numerical software to model them and compare with the laboratory result. From comparing the modelling result and the experimental result, it is observed that the deflection difference of the 7.8-metre plane truss are reasonable and the deflection pattern of the modelling is similar to the experimental. For the 25-metre truss, the deflection differences are high (50-70%) showing that the model may not be reli- able. The limitation of the numerical model is discussed and important area for further investigation is recommended.