Correspondence. 'Design of Network Arches' by Per Tveit, published in The Structural Engineer, July

The paper describes the history, principles of design and construction of the superstructure of the Tasman bridge at Hobart. Reference is made to the probable mode of collapse should a pier be accidentally demolished by a large ship and describes the precautions taken to minimize the extent of damage in such an event. The precasting yards and the methods of fabrication and transport of the various concrete units are described, together with the temporary works for the erection of the river spans. A note is given of the final closure of the old shipping channel and of some experimental work on site. D.H. New, J.R. Lowe and J. Read

The paper discusses briefly the various schemes that were considered for the construction of a 326-ft-high office tower which forms the main element of the building complex at ‘Drapers Gardens and describes in detail the main features of the solution adopted. W.W. Frischmann, G.S. Brown and S.S. Prabhu

This paper describes the design and construction stages of a precast concrete multi-storey factory extension to accommodate nylon-spinning plant and associated ancillary services. The unusually heavy loading conditions on the precast framework and the flexibility required for differing types of plant called for a very careful consideration under extremely tight programme requirements. The paper shows how this task was met by all concerned in the project and illustrates the speed at which non-standard building construction can proceed with objective planning and teamwork. P.B. Edwards and W.J. Prylinski