36
Daratard helps build Hong Kong’s Queen's Road flyover
When a job calls for concrete and the temperature is over 70°, contractors have a major problem-hot weather shortens concrete's setting and placing time and vibra- tion limit and, if placing time is delayed, compressive strength drops.
Mr. Paul Lee, contractor for Hong Kong's new Queen's Road flyover, came up against just this problem. The solution? The recommendation by W. R. Grace (Hong Kong) Limited's technical representatives of the use of Daratarda Grace Specialty Product, specifically designed to extend the vibration limit and delay the setting time of Portland cement.
With the use of Daratard, the contractors were able to meet easily the strict strength requirements specified. Hot weather and concrete don't mix, unless Daratard is in the mix as well. Placement time can then be extended, excessive water is no longer needed, shrinkage and surface cracking are eliminated.
An easily and uniformly mixable liquid, Daratard improves the quality of cured concrete, meets all Federal and ASTM specifications.
Tests by the University of Hong Kong give dramatic proof.
XX 6625
TIME
ADMIXTURE AFTER MIXING
SLUMP (in inches)
28-DAY COMPRESSIVE
(in minutes)
STRENGTH
Nil
Nil
Daratard
Daratard
2382
10
1
5.320 psi
90
0
3,420 psi
10
5,460 psi
90
5,260 psi
(in a 1:11:3 mix)
When the temperature goes up, then, or if more finishing time
is needed, specify Daratard.
For the answer to your construction material problems, consult:
GRACE
CONSTRUCTION MATERIALS
Partners in Construction.
W. R. GRACE (HONG KONG) LIMITED.
303-4 Kayamally Building, Hong Kong. Tel: H-243196. Cable: HKDAREX.
Far East Architect & Builder June, 1967