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Equivalent functional unit in recycled aggregate concrete 321

In order to assess how cement quantity influences the EI, four cement quantity
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ranges (CEM; kg/m ) were pre-defined: CEM # 300; 300 , CEM , 350; 350 #
CEM ,400 and CEM $ 400. Through an evaluation of the strength class influ-
ence (Figs. 11.15 11.17), it can be stated that higher amounts of cement lead to
greater GWP. It was also found that, regardless of the amount of cement, the

3.70E+02 CEM<=300
300<CEM<350
GWP [kg CO 2 eq] 3.30E+02 y = –0.5438x + 319.25
3.50E+02
350<=CEM<400
3.10E+02
2.90E+02
R² = 0.9295
2.70E+02 y = –0.1343x + 314.84
R² = 0.2583
2.50E+02
y = –0.4617x + 352.64
0 20 40 60 80 100
R² = 0.9647
CARC [%]
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Figure 11.15 GWP per m according to the amount of CEM for the class C20/25. GWP,
global warming potential.

4.50E+02 CEM<=300
300<CEM<350
GWP [kg CO 2 eq] 3.50E+02 y = –0.3802x + 294.14
4.00E+02
350<=CEM<400
CEM>=400
3.00E+02
R² = 0.4105
y = –0.1293x + 325.22
2.50E+02
R² = 0.3285
y = –0.3294x + 355.58
2.00E+02
R² = 0.5913
0 20 40 60 80 100 y = –0.5749x + 420.37
CARC [%] R² = 0.5499
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Figure 11.16 GWP per m according to the amount of CEM for the class C25/30. GWP,
global warming potential.
CEM<=300
4.15E+02 300<CEM<350
GWP [kg CO 2 eq] 3.65E+02 y = –0.1487x + 284.47
350<=CEM<400
CEM>=400
R² = 0.7968
3.15E+02
y = –0.0922x + 327.03
R² = 0.3179
y = –0.1147x + 345.42
2.65E+02
R² = 0.122
0 20 40 60 80 100 y = –0.3216x + 411.76
CARC [%] R² = 0.4556
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Figure 11.17 GWP per m according to the amount of CEM for the class C30/37. GWP,
global warming potential.