Abstract:
This study presents the design results of a BS 5950 and Eurocode 3 based Csharp computer program developed for the design of notional laterally unrestrained I-section steel beams. The program accommodates varying beam geometry and loadings. The program development process was categorised into four phases. The first phase was the formulation of design procedures for laterally unrestrained I-section steel beams according to the requirement of BS 5950 and Eurocode 3. The second phase was coding the design outline into computer algorithm using Microsoft Csharp programming language. In the third phase, the developed algorithm was implemented as a computer program using Microsoft Visual Studio. The fourth phase involved the testing of the developed program and validation of design results. Several sets of steel beam models were designed using the developed programs according to the requirements of BS 5950 and EC 3 and the design results were validated using established software –Staad Pro. Those beams were varied in span length. The design results obtained using the developed program were similar to the results obtained using standard software StaadPro. Thus as the span of the beam increases, the maximum bending moments also increase. In the same vein, the buckling capacity increases as the span length and the section modulus of the beam increase; hence the longer the beam, the more it is susceptible to lateral torsional buckling. BS 5950 design results gave a difference of 24.9 % for the area of sections obtained compared with the design results using EC 3 design requirements. This shows that beam designed using the requirements of EC 3 is economical. Besides, this research work has established the similarities and differences in the basis and design procedure of Eurocode 3 and BS 5950.
