Describes, with examples, two methods for proportioning and adjusting proportions of structural grade concrete containing lightweight aggregates. The weight (pycnometer) method uses a specific gravity factor determined by a displacement pycnometer test on the aggregates (Method 1). The weight method also employs the specific gravity factor to estimate the weight per yard of the fresh cement. The samp, loose volume method uses the cement content-strength relationship for the design of all lightweight and sand lightweight concretes (Method 2). Examples are given for systematic calculation of batch weights, effective displaced volumes, and adjustments to compensate for changes either in aggregate moisture content, aggregate proportions, cement content, slump or air content.
Includes US and metric units.
Keywords: absorption; adsorption; air content; air entrainment; cement content; coarse aggregate; fine aggregate; fineness modulus; grading; lightweight aggregate; mixture proportioning; moisture; slump test; specific gravity factor.
Table of Contents
Chapter 2--Factors affecting proportioning of lightweight
2.1--Aggregates--Absorption and moisture content
Chapter 3--Estimating first trial mixture proportions
3.2--Method 1--Weight method (specific gravity pycnometer)
3.3--Method 2--Volumetric method (damp, loose volume)
Chapter 4--Adjusting mixture proportions
4.2--Method 1--Weight method (specific gravity pycnometer)
4.3--Method 2--Volumetric method (damp, loose volume)
4.5--Controlling proportions in the field
5.1--Specified and/or recommended references
Appendix A--Determination of specific gravity factors of structural
Appendix B--Determination of structural lightweight coarse aggregate
Appendix C--Metric system adaptation
Printed / Hard Copy Products: The full and complete returned product will be accepted if returned within 60 days of receipt and in salable condition. A 20% service charge applies. Return shipping fees are the customer’s responsibility.
Electronic /Downloaded Products & Online Learning Courses: These items are not eligible for return.
Subscriptions These items are not eligible for return.
Exchanges: Contact ACI’s Customer Services Department for options (+1.248.848.3800 – ACICustomerService@concrete.org).