Email Address is required Invalid Email Address
In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Learn More
Become an ACI Member
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
Staff Directory
ACI World Headquarters 38800 Country Club Dr. Farmington Hills, MI 48331-3439 USA Phone: 1.248.848.3800 Fax: 1.248.848.3701
ACI Middle East Regional Office Second Floor, Office #207 The Offices 2 Building, One Central Dubai World Trade Center Complex Dubai, UAE Phone: +971.4.516.3208 & 3209
ACI Resource Center Southern California Midwest Mid Atlantic
Feedback via Email Phone: 1.248.848.3800
Home > Tools > Frequently Asked Questions
Q. If time is not available for preliminary tests, how can the desired strengths be ensured? A. Average w/cm strength curves exist, which have been established by many tests in many laboratories for a wide range of materials complying with the specifications of ASTM. ACI 211.1 gives the relationship of w/cm to strength for air-entrained and non-air-entrained concretes. The w/cm is selected based on the required average strength and not the design strength. The average strength exceeds the design strength by a sufficient margin to keep the proportion of low test results within specific allowable limits (ACI 214). It is highly recommended that time be budgeted for trial batching, because that is the only sure way of determining if the desired properties can be achieved with the selected proportions of materials. References: SP-1(02); ACI PRC-211.1-22; ACI 214R-11 Topics in Concrete: Mixture Proportioning; Quality Assurance; Testing of Concrete
Q. If time is not available for preliminary tests, how can the desired strengths be ensured?
A. Average w/cm strength curves exist, which have been established by many tests in many laboratories for a wide range of materials complying with the specifications of ASTM. ACI 211.1 gives the relationship of w/cm to strength for air-entrained and non-air-entrained concretes. The w/cm is selected based on the required average strength and not the design strength. The average strength exceeds the design strength by a sufficient margin to keep the proportion of low test results within specific allowable limits (ACI 214). It is highly recommended that time be budgeted for trial batching, because that is the only sure way of determining if the desired properties can be achieved with the selected proportions of materials.
References: SP-1(02); ACI PRC-211.1-22; ACI 214R-11
Topics in Concrete: Mixture Proportioning; Quality Assurance; Testing of Concrete
Search other resources on the ACI website for answers to technical questions