
Concept explainers
The different ways in which the Concrete Masonry Units are cured.

Answer to Problem 1RQ
The curing of Concrete Masonry Units can be done by low pressure kiln or by autoclaving.
Explanation of Solution
The curing of Concrete Masonry Units (CMUs) can be cured by low pressure steam kiln or an autoclaving.
In a low-pressure kiln, the units are placed on a set before the steam is introduced. This is done for one to three hours with a temperature of 22 oC to 38 oC. The steam produced is then induced which provides moisture to the units. The temperature is then gradually raised to 66 oC to 82 oC, depending on the composition of the concrete. This is maintained for a minimum duration of time until the required strength is achieved.
Autoclaving uses a high-pressure steam where the units are placed in the auto clave for a duration of two to five hours and then gradually steam is provided under a pressure of 150 psi for about three hours. Upon the attainment of maximum pressure and temperature, the units are soaked for 5 to 10 hours and the pressure is gradually released.
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Chapter 12 Solutions
CONSTRUCTION MATERIALS,METHODS...-PKG
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