Guide for Proportioning Concrete Mixtures with Ground Limestone and Other Mineral Fillers

Description

This guide provides recommendations for proportioning normalweight concrete with ground limestone and dust-of-fracture mineral fillers. It is intended to supplement ACI 211.1. Proportioning methods for ground limestone and for dust-of-fracture mineral filler are discussed separately.Mineral filler is defined as a finely divided mineral product at least 65 percent of which passes the No. 200 (75 μm) sieve.

Ground limestone is a purposefully manufactured fine product composed primarily of calcium carbonate and with particles sized within narrow ranges. Ground limestone has been used successfully in concrete in Europe for decades, either added to the concrete mixture separately from the cement or interground with clinker to form portland-lime-stone cement.Dust-of-fracture mineral filler is rock dust created during production, processing, or handling of quarried stone.

Such materials are not purposefully manufactured and can vary in mineral composition and other physical characteristics, depending on the parent stone from which they are derived, the crushing process, and the washing or air separation process.This guide does not address precipitated calcium carbonate or material finer than the No. 200 (75 μm) sieve in natural sand. Although ground limestone typically falls within the definition of mineral filler, it is dealt with separately in this guide from other mineral fillers. It is manufactured under controlled conditions to be a consistent product. Dust-of-fracture mineral filler consisting primarily of calcium carbonate is not considered ground limestone

The selection of constituent materials when propor-tioning concrete with ground limestone or dust-of-fracture mineral filler is very similar to the typical selection process described in ACI 211.1. Mixture constituents such as coarse and fine aggregate (ACI 221R), cementitious materials (ACI 225R; ACI 232.2R; ACI 233R; ACI 234R), admixtures (ACI 212.3R), and water that are commonly used for propor-tioning concrete are usually suitable when proportioning with ground limestone and dust-of-fracture mineral filler.

The most significant adjustments to proportions will be in amount of water used, the type and dosage of admixtures, and minor changes to coarse and fine aggregate ratios.American Concrete Institute – Copyrighted © Material – www.concrete.org2 PROPORTIONING CONCRETE MIXTURES WITH GROUND LIMESTONE AND OTHER MINERAL FILLERS (ACI 211.7R-15)