The American Concrete Institute's Spring Convention was held from March 29 - April 2 in Toronto. The NRMCA Engineering Department summarized committee activity involving department staff.
122: Energy Efficiency of Concrete and Masonry Systems – Kerry Sutton spoke about the challenges of getting ACI 122 adopted at the state and local levels. She provided a report outlining the efforts of ACI and NRMCA in Washington and Connecticut. The committee discussed the successes of ACI 562 and ACI 440 that could be considered as strategies and also discussed how parts of the 122 Guide can be included as references to main document. The committee is working to add more details specific to ICF, Tilt-Up and Precast concrete sandwich panels. It's also looking into comparative analyses between 90.1 and 122 on thermal bridging using Energy Plus in an effort to prove the efficacy of 122.1. ESCSI may have already completed a study that will be reviewed and shared with the committee. Darryl Dixon maintains representation in ACI 122.
201: Durability – The committee continues to work on incremental changes to its Guide to Durable Concrete. Significant revisions to the chapter on freezing and thawing are close to completion. The chapter on corrosion will reflect recent updates to the guide developed by ACI Committee 222. A chapter on chemical attack will be moved forward for review and ballot. Because not much is published for some types of chemical attack, generic guidance will be provided on these aspects. The committee intends to complete the revision of at least 4 chapters in the next two years. The committee also discussed developing information regarding specific durability concerns related to the use of portland limestone cement. Glenn Schaefer is an Associate member of ACI 201 and is active on the subcommittee on chemical attack.
211: Mixture Proportioning – The committee continues to work on several draft documents and is considering if some of the older documents need to be maintained. The committee has surveyed the industry to evaluate whether the water content values in the table of the proportioning guide are typical of what is used in the industry. The survey suggests that the table values are generally higher and may be related to the use of water-reducing admixtures. The committee is also evaluating the tables on coarse aggregate content and the w/cm to strength relationships suggested for trial batches. There was a suggestion to remove values for 2 and 3 in. aggregate as these are seldom used. Glenn Schaefer has requested membership in ACI 211.
212: Chemical Admixtures – The document has been updated and will proceed through the ACI review process. It will include a discussion of some newer admixtures in the revised guide. Glenn Schaefer maintains representation in ACI 212.
214: Evaluation of Results of Tests – The committee balloted changes to additional chapters of the Guide to Evaluation of Strength Test Results of Concrete and will be working on revisions to these chapters. Glenn Schaefer has requested membership in ACI 211.
216: Fire Resistance and Fire Protection of Structures – Revisions to ACI 216.1, Code Requirements for Determining Fire Resistance of Concrete and Masonry Construction Assemblies, have been finalized and will be forwarded to the ACI review process. A Rational Design Guide document is also being developed in parallel. A new task group has been formed on Fire-Induced Spalling to develop potential mitigation provisions for future editions of ACI 216.1. The committee is working on a Tech Note regarding the equivalence of concrete with portland limestone cement to portland cement for fire resistance characteristics. Additional revisions to ACI 219.1 based on revisions to ASTM 119 Table X3.1 published in June 2024 may be incorporated during the Public Comment phase. Shamim Rashid-Sumar maintains representation on ACI 216.
228: Non-Destructive Testing – The committee is working on a considerable revision to its guide document and intends a similar structure with similar levels of detail in all chapters. The discussion is generally very technical and some methods included are not used currently. The current effort is revisions to chapters on Impact Echo and Surface Wave. The committee received a presentation on a new commercial embedded sensor that is designed to be self-calibrating for concrete strength monitoring and not based on maturity. Glenn Schaefer maintains representation in ACI 228.
301: Specifications for Structural Concrete – The committee continues to make revisions to several sections of the specification. Several revisions for consistency ACI 318-25 were approved. Topics in progress include submittal requirements for sustainability, addressing the use of fibers, changes to curing requirements in ACI 318, location of sampling for acceptance tests, lightweight concrete, many provisions in the section on handling placing and constructing, architectural concrete and process of evaluation of shrinkage-compensating concrete. ACI 301 will finalize its revisions for the ACI review process by Fall with the intent to publish the document in 2026. Colin Lobo maintains representation on ACI 301.
318: Building Code for Structural Concrete – ACI 318-25 has been published. A new ACI Committee 318 has been established for the new cycle chaired by JoAnne Browning. This committee will have only six subcommittees with responsibility for specific sections of the Code. The committee will work to publish the next version of ACI 318 in 2031 with a possible supplement in 2028. ACI 318 Subcommittee A is responsible for chapters on concrete materials and construction documents. Sub A reviewed all comments from the review process in the previous cycle to determine Code Change proposals and has identified several items to consider as new business.
Colin Lobo maintains representation on Committee 318, and Subcommittees A (concrete materials) and C (serviceability, loads, analysis and all appendices, including App C on sustainability).
321: Durability Code – The committee continues to develop mandatory language and commentary for a Durability Code. There has been significant progress on most of the chapters. Chapters on Maintenance, Construction and Quality are being developed for the committee ballot. Other chapters have been balloted and comments are being addressed. Glenn Schaefer maintains representation in ACI 321.
323: Low Carbon Concrete Code – ACI CODE-323-25 Low-Carbon Concrete - Code Requirements and Commentary has been published. A new Committee 323 has been established with subcommittees to address specific content. The new ACI 323 Committee is actively shaping the next iteration of the Low-Carbon Concrete Code, introducing sections to advance sustainable concrete construction. The updated Benchmarking and Reduction Section will incorporate Global Warming Potential (GWP) calculations and strategies for carbon reduction. A new Systems section will focus on tailored chapters addressing specific structure types, such as buildings, bridges and infrastructure. The Resilience Section will highlight concrete’s durability and extended life cycle, showcasing its advantages over alternative materials.
Additionally, the Whole Life Cycle Analysis section will evaluate sustainability throughout a project’s lifespan, including maintenance and end-of-life phases, across various applications. The expanded benchmarking guidance will equip local jurisdictions with best practices and statistical tools for establishing carbon reduction benchmarks, complemented by a potential International Benchmarking Appendix to promote global adoption. These efforts collectively aim to provide robust, flexible approaches to lowering concrete’s carbon footprint across diverse projects and regions. Tiffany Reed-Villarreal maintains representation in ACI 323.
327: Roller-Compacted Concrete Pavements – The main committee celebrated and discussed the completion of ACI PRC-327-24 – Roller-Compacted Concrete Pavements - Guide. The document was a major revision of the previous version and was published in December 2024. The subcommittee working on the development of ACI SPEC-327.Y – Construction of Roller-Compacted Concrete Pavements – Specification completed a first draft of the document that will be sent for review of the main committee. Greg Halsted maintains representation as Chair of ACI 327.
329: Performance Criteria for Ready Mixed Concrete – The committee is working on a Guide to Writing a Performance Specification. The guide will use MasterSpec 033000 format for cast-in-place concrete and include recommended language and guidance to the specifier. A ballot to cover Section 1 (General) of the specification was discussed and will be finalized. Three of the five chapters have been completed. Performance requirements and acceptance criteria for different concrete performance properties were discussed for inclusion in Section 2 (Products) of the specification. The committee intends to develop content and ballot Sections 2 and 3. Colin Lobo maintains representation on ACI 329 as secretary.
330: Parking Lots – The committee has started revising 330.2R Guide for the Design and Construction of Concrete Site Paving for Industrial and Trucking Facilities. A task group has been assigned to review and revise each chapter. Proposed revisions to two chapters have been completed; responses to ballots were considered and will be resolved in subsequent online meetings. Amanda Hult maintains representation in ACI 330.
332: Residential Concrete – The committee continues to work on revisions to ACI 332, Code Requirements for Residential Concrete, and resolve negatives from its most recent ballot. The committee is proposing to include performance-based alternatives to w/cm in this Code. The committee received presentations in mini-sessions in support of some of these revisions. The current proposed revisions include the incorporation of NRMCA 100-23 provisions into ACI 332. In addition, the committee discussed updates from ITG12 on 3D Printed (Additive Concrete) Houses and wire reinforcement in residential concrete work. Julian Mills-Beale maintains membership on ACI 332.
522: Pervious Concrete – The 522 Committee was informed that ASTM C1688 on measuring fresh density was reapproved and the method for measuring infiltration in the field, ASTM C1701 is being balloted. The Committee 522 documents - guide and specification - are current and no major updates were needed. The committee discussed the transition of the Pervious Contractor Certification from NRMCA to ACI. A formal approval of this transition from ACI Certification Committee was expected.
The committee scheduled a mini-session to discuss proposed changes to the certification program at the Fall 2025 convention. The committee discussed the participation of ready mixed concrete producers on the committee. It also discussed disseminating information on pervious concrete to designers and engineers and will evaluate opportunities for presentation at different state events. Amanda Hult maintains representation in ACI 522.
551: Tilt-Up Concrete Construction – The committee worked on the comments returned from ACI review process on the Construction Guide and Engineer documents. A representative from PCI summarized its new document on insulated wall panels and efforts to get that and ACI 319 document included in the 2027 ICC Codes. The committee will propose a mini session regarding the use of portland limestone cement in tilt-up construction for the next ACI convention. Darryl Dixon maintains representation in ACI 551.
560: ICF Buildings – The committee continues to work on revising ACI-PRC 560-22 Insulating Concrete Form Design and Construction after discussions on the negative public comments received. NRMCA provided an update on the ACI Foundation research project Investigating ICF construction meeting the requirements of NFPA 285. Shamim Rashid-Sumar maintains representation on ACI 560.
Concrete Innovation Council – The Concrete Innovation Council of the ACI Foundation focused on planning for the CIC Concrete Innovation Forum scheduled for August 12 - 14 in Denver. CIC maintains a portal for inquiries from innovative technology developers and has received several requests for consideration of new technology. CIC discussed the new research funding request process being implemented by the ACI Foundation. Glenn Schaefer is a board member of CIC.
Concrete Research Council (CRC) – The Research Council of the ACI Foundation selects research programs for funding by the Foundation and administers two awards. CRC discussed changes in the process of selecting research topics and funding. In the past, research proposals were solicited, selected and funded at around $50,000. About eight proposals were funded annually. In the new process, ideas on industry challenges will be collected and a steering group between CIC and CRC will prioritize topics and the councils will help define the scope of these projects.
RFPs will be requested for these topics and funding will not be limited to $50k per project. The solicitation of ideas will be open on the ACI Foundation website between July and August and the intent is to finalize funding decisions by January. Information on the process is available on the ACI Foundation website. Colin Lobo maintains representation on ACI CRC.
Other:
ACI Foundation's Concrete Innovation Session – The session was a roundtable/panel discussion with representatives from concrete contractors, material suppliers and the engineering community. The theme was to understand and discuss various aspects of reducing embodied carbon in concrete. The focus was on collaboration between different industry segments and various perspectives on how to best make sure we can move forward with innovation in the built environment. Tiffany Reed-Villarreal, NRMCA director of sustainability codes and standards, served as a panelist, offering insights from her experience in sustainability standards and codes development and underscored NRMCA members’ leadership in advancing low-carbon concrete solutions, emphasizing their practical efforts and fostering connections across industry segments. Glenn Schaefer was one of the session moderators. (Seen here are, from left to right, Michael Cropper, Thornton Tomasetti; Mike Schneider, Baker; Larry Rowland, Heidelberg; Ms. Reed-Villarreal and Joel Ahearne-Ray, Turner. Photo courtesy of ACI.)
ACI 332 (Residential) mini session – Colin Lobo, NRMCA executive vice president, engineering, gave a presentation on Performance-Based Specifications, Test Methods, and Criteria which gave an overview of how performance-based specifications support achieving intended performance and sustainability initiatives. The focus was on using electrical methods such as ASTM C1202 and C1876 as alternatives to requiring a maximum w/cm ratio. ACI 332 is considering these alternatives in their revisions to the ACI residential code. The presentation was useful in convincing some voters of the benefits of performance-based alternatives.
Honoring R. Doug Hooton – Four sessions covered a full day of presentations from a wide range of researchers and industry members, celebrating the contributions of Hooton (professor emeritus at the University of Toronto) on slag cement, use of supplementary cementitious materials, the durability of concrete, performance-based specifications and the evolution of ASTM standards to address current industry needs.
National Ready Mixed Concrete Association