Concrete Case Study
Serviceability Limited State includes defection and crack control. Through researching in the relevant article, the difference in serviceability check is pointed out. It is importance to note that there are the differences in environment between countries and some simplifications in calculation are made in those standards so that this can affect the given procedure and simplified method in different countries.
Crack control is simplified in design standard by the spacing between reinforcement.
The defection includes creep and shrinkage defection. The AS 3600 is the most safe by using effective depth rather than the whole depth. It is clearly discussed
CRACK CONTROL
Comparative crack width results
The crack widths predicted by the different codes have been calculated for a range of varying parameters:
Varying tension reinforcement stress (Figure 9)
Varying cover (Figure 10)
Varying bar spacing with constant reinforcement area and stress. (Figure 11)
Varying bar spacing with constant reinforcement area and maximum stress to AS 3600. (Figure 12)
BS 5400 results have been plotted using a Mq / Mg ratio of 0.1 and 1. All results have used long term values where available. Larger versions of these graphs may be found on the Powerpoint presentation associated with this paper. The following observations can be made from the graph results:
The BS 5400 results using the two different load ratios gave substantially different results, with the higher ratio giving increased crack widths. The BS 8110 results were either approximately centrally placed between the two BS 5400 results, or close to the lower values.
The Eurocode 2 results were usually reasonably close to the mean of the other results.
The CEB-FIP-1990 results were consistently the lowest for high steel stresses and high concrete cover values. Results with varying spacing were close to Eurocode 2 results.
The ACI 318 results were consistently the highest, being close to and
Crack control is simplified in design standard by the spacing between reinforcement.
The defection includes creep and shrinkage defection. The AS 3600 is the most safe by using effective depth rather than the whole depth. It is clearly discussed
CRACK CONTROL
Comparative crack width results
The crack widths predicted by the different codes have been calculated for a range of varying parameters:
Varying tension reinforcement stress (Figure 9)
Varying cover (Figure 10)
Varying bar spacing with constant reinforcement area and stress. (Figure 11)
Varying bar spacing with constant reinforcement area and maximum stress to AS 3600. (Figure 12)
BS 5400 results have been plotted using a Mq / Mg ratio of 0.1 and 1. All results have used long term values where available. Larger versions of these graphs may be found on the Powerpoint presentation associated with this paper. The following observations can be made from the graph results:
The BS 5400 results using the two different load ratios gave substantially different results, with the higher ratio giving increased crack widths. The BS 8110 results were either approximately centrally placed between the two BS 5400 results, or close to the lower values.
The Eurocode 2 results were usually reasonably close to the mean of the other results.
The CEB-FIP-1990 results were consistently the lowest for high steel stresses and high concrete cover values. Results with varying spacing were close to Eurocode 2 results.
The ACI 318 results were consistently the highest, being close to and