Method of calculating the optimal sand content in normal-weight concrete

• Main Author: Leonid Dvorkin
• Format: Article
• Language: English
• Published: Peter the Great St. Petersburg Polytechnic University 2018-11-01
• Series: Инженерно-строительный журнал
• Subjects: concrete mixture; optimal sand content; viscosity; water demand; water separation; the volume of the entrained air; calculation
• Online Access: https://engstroy.spbstu.ru/en/article/2018.83.17/

In the practice of proportioning concrete compositions, the optimum sand content in a mixture of aggregates is usually found empirically. The disadvantage of this approach is the considerable complexity and duration of the required tests. The aim of the work is to develop a calculation methodology for finding the content of sand in the normal-weight concrete, taking into account the optimality criteria given. Based on the well-known theoretical concepts, the design equations are substantiated for finding the content of sand in a mixture of concrete aggregates, which ensures the lowest viscosity of the concrete mixture and prevent water separation. Using the experimental-statistical model, a method is also proposed for finding the sand content in concrete that provides the required volume of entrained air. The proposed calculation methods are confirmed experimentally.