RESEARCH
291
The Department of Civil Engineering completed the development of a simplified method for analysis of wind stresses in tall build- ings, and is undertaking a programme of model testing to examine the theoretical findings. The first stage in the experimental study of the properties of steel portals when encased in concrete and prestressed with high tensile steel wire was concluded and the second stage of the programme was begun. Full scale testing on the behaviour of composite construction using steel beams and concrete slabs was extended from bridge deck structures to the more general cases of grid structures. The testing programme completed during the year on prestressed concrete space frames gave rise to a more detailed programme of testing on plastic hinges in prestressed concrete. The engineering classification and strength studies of local soils from a foundation and stability viewpoint was brought nearer completion. Investigation continued on the bearing capacity of piles in Hong Kong soils but for financial reasons these were terminated during the year. Tests were also carried out on existing multi-storey factories to determine the extent of structural vibrations set-up by reciprocating machinery and the means whereby these could be reduced.
Separate teaching departments for Electrical Engineering and Mechanical Engineering were established during the year, and both carried out active research programmes.
The Department of Mechanical Engineering made an investiga- tion of the boundary layer flow over water turbine blading in an attempt to clarify the scale effect in water turbines. The results of the investigations were published. Studies have also been made of some aspects of the vorticity induced by non uniform flow through cascades. A wind tunnel was constructed and a programme of investigation of the behaviour of water turbine blading at low Reynolds Numbers is progressing. Theoretical research was pursued on the estimation of natural circulation in boilers and the thermodynamics of the regenerative reheat cycle of a power plant.
A series of investigations on the performance of motors under abnormal conditions was undertaken by the Department of Electrical Engineering, but the project will take some years to complete.
The policy of the Department of Architecture is to examine local problems, under staff supervision as part of the projects set