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The aim is to present findings of a theoretical analysis for optimal design of a concrete trough for a new lightweight low‐profile rail track system.

A non‐linear numerical optimisation technique is adopted to predict the minimum area of a pre‐tensioned pre‐stressed trough section satisfying the serviceability and ultimate limit states as per British Standard BS 8110 for critical loading and boundary conditions.

An optimum concrete trough section is calculated to carry all possible load combinations expected during the design life of the track. The performance of the rail, elastomeric pad and track base were found to be satisfactory under the same critical loading and boundary conditions.

The theoretical analysis gives a valuable insight into system parameter values that can optimise design performance and cost. However, these optimal design features now need to be tested experimentally.

To investigate the feasibility of using artificial neural networks for conceptual design of bracings systems for tall steel buildings.

Database of 234 design examples has been developed using commercially available detailed design software. These examples represent building up to 20 storeys. Feed forward back‐propagation neural network is trained on these examples. The results obtained from the artificial neural network are evaluated by re‐substitution, hold‐out and ten‐fold cross‐validation techniques.

Results indicate that artificial neural network would give a performance of 97.91 percent (ten‐fold cross‐validation). The performance of this system is benchmarked by developing a binary logistic regression model from the same data. Performance of the two models has been compared using McNemar's test and receiver operation characteristics curves. Artificial neural network shows a better performance. The difference is found to be statically significant.

The developed model is applicable only to steel building up to 20 storeys. The feasibility of using artificial neural networks for conceptual design of bracings systems for tall steel buildings more than 20 storeys has not been investigated.

Implementation of the broad methodology outlined for the use of neural networks can be accomplished by conducting short training courses. This will provide personnel with flexibility in addressing buildings‐specifics bracing conditions and limitations.

In tall building design a lot of progress has been made in the development of software tools for numerical intensive tasks of analysis, design and optimization, however, professional software tools are not available to help the designer to choose an optimum building configuration at the conceptual design stage. The presented research provides a methodology to investigate the feasibility of using artificial neural networks for conceptual design of bracings systems for tall buildings. It is found that this approach for the selection of bracings in tall buildings is a better and cost effective option compared with database generated on the basis of expert opinion. It also correctly classifies and recommends the type of trussed bracing system.