Presentation: “Shaped by Concrete” PCA’s Integrated Campaign
Presented by Nicholas Ferrari, Portland Cement Associaation
“Shaped by Concrete” is a new educational campaign to increase awareness of the sustainability, resiliency and durability of cement and concrete. The campaign will feature stories based on four themes, exploring how concrete shapes the world around us to make our communities, cities and country better.
There has never been a more important time to explain how and why concrete became – and continues to be – the material of choice for virtually every type of construction through its positive impacts on society.
As we prepare for the challenge’s future generations face, concrete will be even more critical to building a sustainable world for tomorrow.
Technology Showcase: The Science of Seawater-Mixed Cementitious Materials
Presented by Prannoy Suraneni, University of Miami
The use of seawater and other non-potable waters to replace freshwater in concrete can result in a significant increase in concrete sustainability due to freshwater savings. While seawater cannot be used in conventionally reinforced concrete, usage in unreinforced concrete or concrete reinforced with non-corrosive reinforcement appears to be possible. The effects of seawater on hydration, microstructure, strength, and shrinkage of cementitious materials are discussed. Gaps in knowledge and potential durability issues are also highlighted. The potential applications of seawater-mixed concrete and major barriers towards technology adoption are discussed.
Technology Showcase: Handheld Instant Air Meter – Fresh Total Air and Specific Surface in Situ
Presented by Marc C. Ramsey, Creare Incorporated
Creare has developed a new instrument that provides an instantaneous, in-situ measurement of both void fraction and specific surface in fresh concrete. This simple, robust, handheld wand can be inserted into any un-cured concrete sample and returns an accurate result at the touch of a button, enabling real-time monitoring at the plant or jobsite. I will demonstrate the operation of the instrument and present initial validation data.
Presentation: Recent Developments and Initiatives from ACI Committee 222 on Corrosion of Metals in Concrete
Presented by David Tepke, SKA Consulting Engineers, Inc.
ACI Committee 222, Corrosion of Metals in Concrete, has recently revised the Guide to Protection of Metals in Concrete Against Corrosion. Due to the significant impact to the industry, considerable variation in existing approaches and serious consequences of corrosion, the committee has also recently promoted initiatives associated with refining chloride limit recommendations for new construction and chloride threshold testing. This includes a recent Special Publication on chloride limits, revision of recommendations in the new guide, and sponsorship/oversight of CRC funded research for a collaborative study for the development of a standard critical chloride threshold test method. This presentation will discuss some of the key updates to the Guide Document, as well as recent initiatives associated with chloride limits and thresholds. It will also discuss consequences of corrosion, the reasons why these issues are important, impacts to the industry, progress and future needs.
Presentation: Resiliency and Concrete
Presented by Aditya Bhagath, Thornton Tomasetti
Extreme weather events like flooding, hurricanes, and heatwaves are increasing in intensity and frequency leading to concerted efforts by regulatory authorities to mitigate the impacts of these events on people and the economy. In the face of these challenges, resilient construction practices can help communities recover safely and successfully from a disaster. The presentation seeks to provide insight on the business case for resilience, the advantages and challenges posed by concrete to the designers that specify resilience measures and overlap between sustainability and resilience.
Panel Presentations: What the New Durability Code Will Mean to You
Moderated by Lawrence Sutter, Michigan Technical University, and presented by R. Doug Hooton, University of Toronto; Oscar R. Antommattei, Kiewit Engineering Group Inc.; Cary kopczynski, Cary Kopczynski & Co., Inc.; Brian H. Green, US Army Corps of Engineers
While most ACI 318: Building Code Requirements for Structural Concrete (ACI-318) components are in benign exposures and requirements are perfectly satisfactory, there are components that are in durability exposures that can cause premature degradation. Currently, in ACI-318 exposure classes are identified and limits are placed on properties such as w/cm and strength that are only indirectly related to durability. However, simply specifying such limits on concrete mix design, and cover depth, do not provide a comprehensive design methodology for preventing premature degradation, as has been shown in parking garages and in locations near the sea. Issues such as thermal and drying shrinkage cracking may be more prevalent in high cement content, low w/cm mixtures. In addition, many concrete applications are not governed by the ACI-318 Code.
The goal of ACI 201 is not to interfere with what is currently in the ACI-318 Code, but to provide more comprehensive design requirements or considerations that could be adopted as alternatives, if invoked, in cases where there are durability exposures and that would also cover non-318 concrete applications, especially for infrastructure applications where long service life in severe exposures is expected and demanded by owners.
Presentation: Code Advocacy and Outreach for ACI 562
Presented by Kerry Sutton, American Concrete Institute
In 2019, ACI submitted a code change proposal to the International Code Counsel (ICC) for the purpose of referencing ACI 562-19 Code Requirements for Assessment, Repair, and Rehabilitation of Existing Concrete Structures and Commentary in the 2021 International Existing Building Code (IEBC). The results of this code process and the unique challenges and obstacles to achieving adoption will be discussed. In addition, recommendations for moving forward and the importance of engaging ACI Chapters and local members in code advocacy and outreach efforts will be presented.
Presentation: The DOT Mindset and Embracing Innovation
Presented by Andrew Johnson
State highway agencies have different goals and incentives from the private sector and may seem inscrutable to those who have not worked in government. This goes for the agencies as a whole and individuals who are career professionals within the agency. This presentation will discuss the avenues that commonly exist for approval and implementation of new materials and methods. The presentation will also discuss what items are commonly missing from most submissions to agencies, based on the speaker’s experience as a retired DOT engineer.
Presentation: Recap of the Concrete Construction Productivity Workshop
Presented by G. Terry Harris, GCP Applied Technologies
A diverse set of stakeholders (architects, engineers, general contractors, subcontractors, concrete producers, material suppliers, digital technology suppliers, automation technology suppliers, owners, researchers, and industry associations) participated in a workshop on Tuesday, February 11, 2020 to develop a network to evaluate the productivity of the concrete construction sector and identify solutions to improve productivity. The following questions were explored:
- What are the appropriate metrics for productivity in the concrete construction sector?
- What are the drivers of productivity for stakeholders in the sector?
- What is the potential for proposed solutions to improve productivity?
This presentation is a recap of the major discussions that took place and the progress made towards creating a roadmap for evaluating and improving productivity for the concrete construction sector.
Presentation: New Priorities – Embodied Carbon in Concrete Construction
Presented by Michael E. Cropper, Thornton Tomasetti, Inc.
Assessing and reducing embodied carbon in the built environment has recently become a more widespread design criteria for building owners and the industry as a whole. In large part because LEED and similar rating systems have facilitated significant progress in reducing operational carbon, carbon emissions from initial building construction are expected to match those of operational emissions for projects constructed between 2020 and 2050. This presentation provides an overview of embodied carbon as well as recent industry and regulatory efforts to reduce the global warming impact of the built environment. Through examples and case studies, various design and construction concepts will be presented to illustrate both the challenge and opportunity of using embodied carbon as a design criteria.
Presentation: Atlanta International Airport Case Study – Installation of Mass Concrete Piers
Presented by Justis Brogan; Anthony Gorzelnik; Will Holcomb
The concrete piers used to support the new canopy at Hartsfield-Jackson Atlanta International Airport were classified as mass concrete after the team poured the first pier and measured elevated curing temperatures. The team had to design and implement the active cooling system used to regulate internal temperatures on the fly while achieving the construction schedule to support canopy installation. At the worlds most travelled airport, the planning and logistics coordination that went along with this unforeseen condition was a monumental challenge. The team was able to rise to the challenge by pouring and curing all concrete piers prior to when the canopy steel was scheduled to be set.