Home › B.Tech Civil › civilengineering › Concrete Admixtures › Per §4.4, calcium chloride must NOT be used in w…
Per §4.4, calcium chloride must NOT be used in which of the following concretes?
A{'text': 'Plain mass concrete with ordinary Portland cement', 'label': 'A'}
B{'text': 'Rapid Hardening Cement concrete (general use)', 'label': 'B'}
C{'text': 'Prestressed concrete or stray-current exposure zones', 'label': 'C'}
D{'text': 'Reinforced concrete with a low water-cement ratio', 'label': 'D'}
Answer & Solution
Correct answer: C. {'text': 'Prestressed concrete or stray-current exposure zones', 'label': 'C'}
1. §4.4 reads: 'the same should not be used in prestressed concrete because of possible stress corrosion of prestressed steel. It also should not be used where stray electric currents are expected.'
2. CaCl2 is also forbidden with aluminous cement.
_Source: IGNOU ET-522 Block-1 Unit-4 Admixtures, §4.4, p. 47_
Related questions
Per §4.14, steel embedded in fresh / hardened concrete is protected from corrosion mainly Per §4.13, the use of a pozzolanic admixture does NOT typically achieve which of the folloPer §4.13, pozzolana is best characterised (per IS 3812 Part II 1981) as a material that:Per §4.12, Category B superplasticizers are chemically known as:Per §4.12, superplasticizers can typically reduce the water content of a concrete mix by aPer §4.9, the most commonly used gas-forming admixture in concrete is:Per §4.7.4, the dosage of air entrainment for ordinary concrete should generally be kept wPer §4.7.3, the strength loss in concrete per 1 percent of entrained air is generally repo