Proportioning with Ground Limestone and Mineral Filler-Utilzation of Crushed Stone Mineral Filler (Microfines) in Ready Mixed Concrete (recorded presentation)

Utilzation of Crushed Stone Mineral Filler (Microfines) in Ready Mixed Concrete (recorded presentation)

Video Transcription

Video Summary

The presentation focused on the use of number 10 screenings, a waste material from quarries, in concrete mixtures. Commonly combined with manufactured sand, these screenings are often seen as undesirable due to high fines content but present an economic opportunity for concrete producers. The speaker explained the engineering properties of the screenings, including compressive strength, flexural strength, and shrinkage, noting the benefits of combining them with natural sand for a balanced fineness modulus. Batch plant adjustments, such as bin modifications and air cannon installation, were discussed to address flow issues associated with the screenings' higher moisture content and stickiness. The importance of assessing clay content in the screenings was highlighted, especially the presence of problematic smectite clays, using tests like the recent ASTM C1777. The presentation concluded that, with proper proportioning and plant adjustments, number 10 screenings can be effectively utilized in concrete production, saving costs and utilizing waste materials.

Keywords

number 10 screenings

concrete mixtures

engineering properties

batch plant adjustments

clay content

ASTM C1777