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Per §5.6, harmful effects of bleeding listed in the source include all of the following EXCEPT:
A{'text': 'Formation of weak laitance at the surface of each pour', 'label': 'A'}
B{'text': 'Increased permeability if w/c is over 0.7 (continuous bleeding channels)', 'label': 'B'}
C{'text': 'Reduction in bond between aggregate and paste, and between bars and concrete', 'label': 'C'}
D{'text': 'Increase in the long-term compressive strength of hardened concrete', 'label': 'D'}
Answer & Solution
Correct answer: D. {'text': 'Increase in the long-term compressive strength of hardened concrete', 'label': 'D'}
1. §5.6 lists three harmful effects of bleeding: laitance at the surface, increased permeability (water/cement above 0.7 leaves continuous bleeding channels), and reduction of bond between paste and aggregate and between concrete and the reinforcing bars (especially cranked bars).
2. Bleeding does NOT increase long-term compressive strength — quite the opposite, by leaving a porous structure and lowering bond.
_Source: IGNOU ET-522 Block-2 Unit-5 Workability & Fresh Concrete-I, §5.6, p. 15_
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