Compliance of Cement Concrete Produced Based on Previous Prepared Job-Mix Formula: Case Study

Abstract

The primary focus of construction is on concrete quality control to ensure compliance with manufacturing standards and fulfill its intended purpose. This study investigates the compliance of compressive strength requirements for Portland cement concrete used to manufacture precast New Jersey barriers, based on a previously prepared job-mix formula. The methodology involved selecting 90 cube specimens (150×150×150 mm) and testing them by applying compressive pressure after 28 days of curing. The evaluation methods followed the standards of the British and American Concrete Institute. The study found that the compressive strength of the new concrete mixture complied with the American statistical method, with a 3.4 MPa margin of safety and excellent concrete control. However, according to the British methodology, the initial production period did not meet compressive strength compliance due to only a marginal increase in strength compared to the required value. Nevertheless, the continuous production period satisfied the compliance requirements. The potential to utilize previously prepared job-mix formulas with comparable characteristics depends on the materials meeting the required property standards. There is a cost-benefit advantage due to reduced delays.