As the supply of traditional SCMs, such as coal fly ash and ground granulated blast furnace slag, becomes limited, newer SCMs may be needed for concrete to meet performance, sustainability, and durability goals. Herein, Engineered or Activated SCMs can be promising materials that are now being introduced in the market. Specifically, work on the conversion of inert feedstocks into value-added SCMs through novel methods has recently become more widespread. In this session, speakers will discuss various processes, including but not limited to thermal, mechanical, and chemical activation, that can be used to engineer SCMs. The material properties of these newer SCMs and their performance in concrete will be discussed.
Learning Objectives:
(1) Understand different activation processes that can be used to convert inert feedstock into SCMs, including scalability;
(2) Understand the kinds of feedstocks that are most suitable for activation;
(3) Understand the material properties of engineered SCMs, such as reactivity and water demand;
(4) Understand how activation processes can lead to sustainable and durable SCMs.
Predicting Reactivity Within Minutes via UR2: Results on 200+ SCMs
Presented By: Nishant Garg
Affiliation: University of Illinois Urbana-Champaign
Description: Nowadays, there is a growing interest in the development of “Engineered SCMs” where relatively inert feedstocks are transformed into high-quality, value-added SCMs. Herein, the standard method to evaluate SCM performance in terms of its reactivity is the 28-day SAI. In order to speed up screening and qualification, in 2016, the 7-day R3 test was introduced. To further accelerate iterative R&D, and enable real-time QC/QA of such engineered SCMs, we introduced the 5-minute Ultra-Rapid Reactivity (UR2) in 2025. In this presentation, I will share the latest results on a dataset of 140+ calcined clays and 60+ fly ashes where the UR2 test can reliably predict both 7-day R3 and 28-day SAI results in a matter of a few minutes. Finally, I will touch upon our next step of validating the UR2 test on 40+ natural pozzolans as well as preliminary results on operator effect and precision of the method.
Carbonate SCM: Wait, What Calcium Carbonate is an SCM?
Presented By: Craig Hargis
Affiliation: Fortera
Description: Vaterite is the least stable anhydrous crystalline form of calcium carbonate, and it is produced through a thermal and aqueous process that will be explained. Performance results from the laboratory scale to large commercial field trials will be shared. Finally, a case will be made for why calcium carbonate is more than a mineral filler and it should be treated as a supplementary cementitious material by the cement and concrete community.
OPUS SCM: Low Carbon Engineered SCM
Presented By: Evelien Martens
Affiliation: Terra CO2 Technology
Description: Terra’s OPUS SCMTM is an economic and sustainable SCM, developed to answer the growing demand for SCM and decrease the reliance on carbon-intensive Portland cement.
OPUS SCM is made from abundant, locally available non-carbonate silicate rock. Construction aggregate, which is already quarried in or near every large metropolitan area, is often suitable as feedstock.
The product, OPUS SCM, has been extensively tested in concrete, both in the lab and in field demonstrations and meets rigorous performance standards. OPUS SCM can offset the use of up to 40% of Portland cement in most common concrete mix designs. It is a drop-in solution which works seamlessly with today’s infrastructure, enabling the construction industry to decarbonize without sacrificing quality or affordability.
Terra has been operating a 1 TPD facility in Golden, CO since 2022 and is currently building the first commercial plant in the Dallas-Fort Worth area, which will be commissioned in 2027.
Activated Pozzolans from a Coproduction Process with Portland Cement and Alumina
Presented By: Will Nguyen
Affiliation: Brimstone Energy
Description: As the construction industry progresses towards concrete with reduced global warming potential, demand for low-carbon supplementary cementitious materials (SCM) remains high. Brimstone is a startup company that uses a novel process to produce activated pozzolans from calcium-rich silicate rocks like basalt while also coproducing portland cement and alumina. Chemical activation of the rocks is achieved through leaching. Laboratory results show the activated pozzolan exhibits a strength activity index (ASTM C311) of over 100% at a testing age of 28 days and a cumulative heat release (ASTM C1897) of over 200 J/g at a testing age of 7 days.
Engineering Granulometry to Enable High-Performance SCMs from Reclaimed Ash
Presented By: Russell Hill
Affiliation: Revantec Solutions
Description: As supplies of traditionally produced fly ash decline, the concrete industry is increasingly dependent on reclaimed and heterogeneous ash sources. This transition shifts SCM production from material selection to material engineering, requiring new approaches to control performance. This work evaluates how engineered granulometry, through wet classification, grinding, and blending can convert variable reclaimed ash into consistent, high-performing SCMs. Processing enables control of particle size distribution, shape (sphericity), surface area, and surface activation, providing levers to optimize the critical balance between reactivity and water demand.
Results from laboratory studies and ongoing university research (UIUC) indicate that blends combining fine, activated fractions with spherical classified materials can enhance reactivity while maintaining workable rheology. Particle packing-based modeling is used to design optimized systems, which are validated in paste and mortar. This approach demonstrates a pathway to scalable, engineered SCMs for low-carbon concrete.
Activated Electric Arc Furnace Slags: Performance and roadblocks
Presented By: Sivakumar Ramanathan
Affiliation: University of Miami
Description: Alternate supplementary cementitious materials (SCMs), mainly industrial waste products, are being considered to replace the conventional SCMs such as fly ash and ground granulated blast furnace slag. Alternate SCMs in their raw form are usually disposed of in landfills and need to be activated to ensure adequate levels of reactivity for use in construction. One such alternate SCM is electric arc furnace slag.
Electric arc furnace (EAF) slag is relatively inert in its raw feedstock form and may contain periclase and free lime. These deleterious phases can cause expansion of concrete. To address these issues, carbon upcycling technologies uses a patented mechanochemical activation process which carbonates the deleterious phases while increasing the reactivity through mechanical and morphological changes. Isothermal reactivity, strength, and water demand results combined with mineral compositional changes will be used to understand how different types of comminution can alter performance while satisfying the limits of energy consumption.
Beyond SCM, Valorization of BOF Slag through Activation
Presented By: T Wattez
Affiliation:
Description: The most known and widely used are coal ash and blast furnace slag, whilst large amounts of other industrial by-products remain untouched. One of the interesting candidates is basic oxygen furnace (BOF) slag, also known as LD-slag or converter slag. It’s pure SCM performance has been demonstrated to be poor, associated with durability concerns due to the variable amount of free lime BOF slag contains.
By considering its chemical and mineralogical features which are essentially a high Ca/Si ratio (>3.0), high total Fe content and the presence of clinker like-phases (C2S and C4AF), we design a dedicated organics-based activation system that unleashes the hydraulic potential of BOF Slag. Based on those findings, several binder compositions were adopted to test mechanical and some initial durability factors on a concrete scale.
Cost-Competitive SCMs, Produced Anywhere Cement Is Made
Presented By: Daniel Kopp
Affiliation: Queens Carbon
Description: Cement production accounts for approximately 7 - 8% of global CO2 emissions, creating urgent demand for supplementary cementitious materials (SCMs) that enable deep clinker reduction without compromising performance or cost. Conventional SCMs are constrained by geography, variable quality, and declining industrial byproduct supply.
Queens Carbon is producing a new class of engineered SCMs derived directly from limestone, sand, and clay – the same abundant raw materials used by the cement industry. By producing SCMs from conventional cement feedstocks, Queens Carbon removes supply limitations and enables scalable localized production wherever cement is manufactured.
This presentation outlines Queens Carbon’s SCM production methodology, presents mortar and concrete performance data at meaningful clinker replacement levels, and evaluates projected production costs relative to clinker and traditional SCMs. Results demonstrate that engineered Q-SCMs achieve substantial clinker reduction while maintaining strength, durability, and constructability.