February_1971 — Page 30

Computer design service in Hong Kong

by Andrew Jean

Structural Computing Services

SINCE the industrial Revolution man has employed machines to augment his own muscle power. The introduction of electronic computers has meant that he is now able to augment his in- tellectual powers too.

Science, engineering and industry have quickly adopted the added brain- power of the computer and in the con- struction industry

―

not normally

noted for its quick acceptance of new methods - there is a rapidly widening acknowledgement of its usefulness.

In every country, developing and developed, there is a need for shorter design schedules, brought about by rapidly rising labour and material costs. The high cost of capital itself has reinforced this need. And because of time-cost factors, projects which have previously been performed sequentially must now be carried out concurrently as far as is possible.

The words 'redesign and modifica- tion of plans' are dreaded by most architects and engineers. But where once they could mean months of tedi- ous calculation, today with the aid of computers both redesign and optimum design can be achieved with ease and the results may be obtained in a mat- ter of hours.

Aside from the significant savings in design time, computerized design in building offers at least three other advantages:

1. It frees the designer from repeti- tious, routine jobs, allowing him to devote his time to more complex and creative tasks.

2. It allows the designer to incor- porate last minute changes quickly and easily into the program.

3. It results in a finished structure representing the best balance of econo- my and structural safety, eliminating the common temptation to overdesign 'just to be on the safe side'.

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IBM 1130 computer installation

Finally, the use of computers in building design allows the experience of the ablest engineer to be extended to all those working on a project. This communications link is one of the most important assets of computer

use.

In Hong Kong, Structural Comput- ing Services has developed programs for both the analysis and design of reinforced concrete and prestressed concrete structures. These programs are available to all architects and en- gineers in the colony, and in April this year it is planned to make them avail- able to other areas of S.E. Asia.

The programs are specially design- ed to produce final member sizes and quantity of materials of structures for use in cost comparison and for actual

construction.

Programs

1. Rectangular frame

This program will analyse a frame of up to nine bays by 50 storeys for any of the following applied joint loads (forces

(forces or moments), any number of different types of loading applied to any of the columns or beams. The method is based on an iterative solution. It does not include member shortening. Missing members are permitted only on upper floors in cake tier fashion. Output includes all input, total fixed end moments and simple beam shears, distributed moments and shears at the ends of every member, column axial loads and horizontal floor deflection.

2.

Simple beam analysis (optional cantilever) - any loading

Program will determine all analysis information necessary for either a simple beam or a simple beam with To date some 31 programs have cantilever, as a result of loading the been devised. These include:

beam with any combination of dif

Far East BUILDER, February 1971

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ferent kinds of live and dead loads.

Loads may be independently chosen from any of 16 basic types or shapes and will be combined with each. other to produce maximum live and dead load moments and deflection coefficients. Live load is skip loaded to produce maximum design values. Moment values are given at 1/12 points for various load conditions.

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3. Prismatic continuous beam ulti- mate strength

Program will determine complete dead and all possible skipped live load shears and moments for a continuous beam of up to 12 spans with columns above and below. Loadings may be chosen from any of 18 types of dia- grams to be combined. Max. negative moment curve, max. positive noment

Major input data are as follows

Mark Number FLR27BNT 6