Title: ASTM Accelerated Strength Tests for Quality Control of Concrete
Author(s): V. Ramakrishnan and J. Dietz
Publication: Symposium Paper
Appears on pages(s): 95-116
Keywords: accelerated tests; compressive strength; concretes; expan-sive
cement concretes; quality control; research; statistical analysis.
The accelerated curing methods recommended by the American Society for Testing and Materials were adopted for estimating the potential strength of con-crete used in the western South Dakota. Cylinders were made and tested from 21 different batches of concrete used in the construction of buildings, bridges, and pavements. These concretes were supplied by two local ready-mix concrete producers, one using the central-mixer technique and the other using the transit mixer operation. Ranges of variables included in this investigation were, types of cements (Type I, Type II, and Type K), types of molds (steel, plastic and cardboard), water-cement ratios (by weight) 0.41 to 0.72, aggregate-cement ratios (by weight) 2.5 to 4.1, maximum size of coarse aggregate 1 inch, and the 28-Day Compressive Strengths 3400 to 6800 psi (23500 to 46900 kPa). An equation and correlation curves are presented for the locally used materials and mixes relating the strength of Type I, Type II and Type K cement concretes obtained in the accelerated curing methods and the 28-day strength obtained with standard curing conditions. Analyzing the results from this investigation and the results from other investigators from various parts of the world, an equation applicable universally with reasonable ac-curacy is presented for estimating the potential strength of concrete using the boiling water method.