Title: Monitoring Concrete Operations With the CQC Report--Case Study

Author(s): V. Novokshchenov and D. Allum

Publication: Symposium Paper

Volume: 141

Issue:

Appears on pages(s): 241-264

Keywords: batching; bridges (structures); compressive strength; control charts; fresh concretes; microcomputers; models; quality control; standard deviation; statistical analysis; General

DOI: 10.14359/3995

Date: 12/1/1993

Abstract:
Describes the results of inspection of concrete operations and quality control of concrete at the Valley Bridge Project in Bluffs, Illinois, using a computer model, the CQC REPORT. The following variables affecting potential durability and strength of concrete in bridge structures were evaluated: accuracy of measuring of concrete materials, state of control and capability of batching operations, variations in SSD quantities of ingredients per cubic yard of concrete, yield, control over the water-cement ratio, properties of freshly mixed concrete, age of concrete at discharge, compressive strength of concrete cylinders, standards of control over concrete manufacture and concrete testing, amount of rejected concrete, and reason for rejection. Paper is concerned with the 6000 psi (41.4 MPa) concrete mix supplied for bridge spans from one of two batch plants used on the job. Paper also describes the structure of the CQC REPORT and statistical techniques used to analyze test data.