View of the Temple from the Racecourse.
11' 0", the floor of the latter being raised above that of the hall. Lino- leum carpets with a yellow square design cover the entire floor, on which only bare feet are allowed to tread, all shoes being removed at the door. Velvet curtains can be drawn across the front of the vimana to separate it from the hall. The vimana contains a stone altar decorated in gold and silver. which contains the marble statue of Lakhshmi Narain, specially brought from India.
A covered way runs the whole length of the back of the building, from which access may be had to the priest's room, a store, the kit- chen and lavatories.
Architect: Mr. Fung Tsun General Contractors: Wing Hing
Construction Co.
Steel Windows: Enterprise Met-
al Window Company Sanitary Fittings: Sun Loong &
Company
THE FIRE RESISTANCE OF PRE-STRESSED CONCRETE
(Reproduced by Permission from the Fire Protection Association Journal)
The behaviour of pre-stressed con- cover to the cable as a precaution crete during and after fires is being studied at the Fire Research Station. Elstree, with particular reference to post-tensioned beams. One series of tests has been completed. Further investigations are being made to ob- tain confirmation on certain points.
against spalling if the thickness is den. There is a progressive sagging, (6) Failure is unlikely to be sud- increased beyond about three inches. which in beams of large span would For a fire resistance of four hours or more an insulating encasement is
be most noticeable. The formation probably required.
and visible extension of cracks with a marked increase in deflection are (2) Normal in situ plastering with signs that collapse is imminent, gypsum or cement lime sand may The type of beam selected for these give up to half an hour resistance ad-
(7) Beams which have been expos- tests was a pre-cast element of ditional to the two hours attained ed to a fire of shorter duration than rectangular or I-section which was with pre-stressed concrete having that which would cause failure, fully pre-stressed before a narrow 2 1 2 inches cover to the cable if representing, say, less than half of concrete strip representing a floor there is an adequate key with the their fire-resistance, are likely to re- slab was cast on top and keyed to the concrete. Protection incorporating tain a high percentage of their ori- beam. Concrete of the same com- vermiculite when applied one inch ginal strength on cooling, but with a position was used throughout and the thick should increase the fire resis- marked residual deflection and loss size of wire and initial stress in the tance by about two hours.
of pre-stress. wire were the same in all specimens. The aim of the tests was to observe within certain limits the effect on fire resistance of load, restraint, concrete cover to the cable, and size of beam, together with the improvement given by protective encasements.
(3) Beams may fail a little earlier In general the greater the load if longitudinal expansion is prevented the earlier is the failure but it was than if they are free to expand. The found that with certain types of effectiveness of the restraint is a de- beam, failure might occur earlier termining factor, but the results so when they are very lightly loaded far do not permit a quantitative than when fully loaded. statement to be made.
presentative
full scale span, since beams are used in spans larger than
the capacity of the testing equipment
Although the following conclusions
The tests were carried out with are tentative, being based on a small
(4) There is little difference in 1 2, 3 8 and 1/4 scale beams of a re- number of tests, there are reasonable performance between a beam of rect- grounds for believing them valid. angular section and an I-beam having the same load-carrying capa- (1) Time to collapse is determined city and the same concrete cover to largely by the rate of rise of tempera- the cable. ture of the cable. A fire-resistance of two hours can be obtained with a (5) Explosive spalling, which was concrete cover to the cable of about observed in very small units made operation of the Building Division of 2 1 2 inches. Longer periods are like- with gravel aggregate, does not seem the National Bureau of Standards in ly if the cover is increased, but it likely to occur in beams having no the United States has been obtained may be desirable to include a light part less than about two inches total in order to carry out tests on 4 5 scale reinforcement, say steel mesh, in the thickness.
beams.
at the Fire Research Station. Before the results of the reduced scale tests are scaled for full size beams, the co-
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