| Estimation of the concrete
volume displaced by reinforcement
|
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| volume of section occupied by reinforcement | |||||||||
| reinforcement ratio | 155 | kg/cu.m. | |||||||
| . | |||||||||
| = | 0.019872 | cu.m./cu.m. | [taking steel density as 7800 kg/cu.m.] | ||||||
| steel volume = | 2.0% | ||||||||
| eg: T40 bars at 125 ctrs c/w T25 bars at 150 ctrs top mat and T25 bars at 150 ctrs both ways in bottom mat of 1m deep section | T40 | volume = | 10053 | sq.mm./m. | top mat | ||||
| T25 | volume = | 3272 | sq.mm./m. | top mat | |||||
| T25 | volume = | 3272 | sq.mm./m. | bottom mat | |||||
| T25 | volume = | 3272 | sq.mm./m. | top mat | |||||
| total = | 19870 | sq.mm./m. | |||||||
| hence ratio = | 1.99% | ||||||||
| Estimation of concrete losses within the delivery vehicles | ||||||
| grout coat to drum | =6mx6mx1mm max.= | 36 | litres / load | |||
| av. load = | 5.4 | cu.m. | ||||
| left in drum / washout | say | 10 | litres / load | |||
| total = | 46 | litres / load | ||||
| 10% not carried over to next load | ||||||
| total waste / pour = | 5 loads at 10% + 100% | = | 0.069 | cu.m. | ||
| average pour size = | 35.3 | cu.m. | ||||
| waste = | 0.20% | |||||
Estimation of concrete volume used in testing |
|||||
| strength | rheology | ||||
| sampling rate | 1 sample per 20 cu.m. | 1 sample per 6 cu.m.or part thereof | |||
| sample size | 18 | 12 | litres | ||
| volume taken per cu. m. | 0.9 | 2.0 | |||
| average pour size = | 35.3 | ||||
| total = | 2.90 | l/cu.m. | |||
| = | 0.29% | ||||
| per av. pour | 108 | litres = | 0.31% | ||
Last Updated on 17/08/98
By Stephen Deeble, htmk by Alan Bond
Email: alan.bond@aber.ac.uk