Displaying items by tag: National Ready Mixed Concrete Association

Betolar has called today for a global performance-based standard to replace existing prescriptive standards. Riku Kytömäki, the head of Betolar, argued at the London-based Concrete Expo that the lack of a performance-based standard is holding back the use of low-carbon materials from replacing cement in concrete production. He said “the current regulations across the markets are restricting the use of circular materials allowed in concrete buildings.” Betolar produces Geoprime, an additive designed for use in cement-free concrete production with ash and ground granulated blast furnace slag (GGBFS). This gives the company a financial reason to want standards to change, as it will potentially allow it to sell more of its product. However, as the company points out, “there is a huge need for new alternatives.” The world needs around 4Bnt/yr of cement but there is only 300Mt/yr of slag available.

Building materials producers and related companies wanting to change rules and standards in response to new trends is a common refrain. For instance, the increased use of alternative fuels by the cement sector has prompted all sorts of regulatory changes. However, rather than simply asking for amendments to the existing ways of doing things, Betolar is advocating for more wholesale change. It isn’t alone. Also this week the ASTM in the US announced that it is writing a specification to include a wider range of secondary cementitious materials (SCM). In addition, many of the interviews Global Cement Magazine has conducted with companies developing and marketing new types of cement and concrete in recent years have said similar things. Examples include the use of graphene, carbon nanotubes or sequestering CO₂ into industrial by-products to create novel secondary cementitious materials (SCM).

Prescriptive versus performance-based approaches to buildings and building materials tie into wider design philosophies about construction. The prescriptive approach provides detailed descriptions of regulations, methods and components, such as cement and concrete standards. With respect to concrete standards, this might mean setting mandatory SCM and cement proportions, determining allowable water content, certain types of aggregate to be used and so on. The performance approach focuses on the end results, although it can be just as codified and standardised as the prescriptive route. For concrete, for example, this means that performance is measured by standard test methods with defined acceptance criteria stated in the contract documents with no restrictions on the parameters of concrete mixture proportions.

For cement and concrete standards the prescriptive approach dominated in Europe and North America in the 20th century. However, this began to change in the US in 2002 when the National Ready Mixed Concrete Association (NRMCA) started working on its roadmap towards its Prescription to Performance (P2P) initiative. The key aim of the scheme was to shift the emphasis from prescribing (or indeed proscribing) the ingredients and their proportions in a concrete mixture to an emphasis on the performance properties of the combined materials. A decade later in the mid-2010s it found during a progress review that about half of the sample of project specifications studied were classified as ‘prescriptive.’ The biggest prescriptive restriction was on the quantity of SCMs set by specification writers. These were often percentages required in certain circumstances, such as freezing and thawing cycles, but imposed on all usage.

The current bout of interest in performance-based standards appears to be driven by the growing demand for cement and concrete products to lower their clinker factor by using higher amounts of SCMs. A far wider range of SCM-based products are being developed and coming to market and then encountering regulatory burden. These new material manufacturers are meeting up with the sustainability lobby, which also has an interest in decarbonising building materials. In 2022, for example, the Belgium-based Environmental Coalition on Standards (ECOS) started pushing for performance-based standards for cement. In a statement it said that, “it is commonly accepted that prescriptive specifications are convenient, but that this convenience is obtained at the expense of (eco-) innovation and decarbonisation.” It added that the switch to performance-based standards would also strengthen the European internal market for construction products as part of the Construction Products Regulation (CPR). It noted the ASTM standards for hydraulic cements (ASTM C-1157), that were developed in the 1990s in the US, and more recent developments in the field in Latin America.

It is worth pointing out that the prescriptive route does have its advantages. Using a prescriptive system is easier for less-experienced practitioners or generalists as it sets a minimum standard, even if it is over-engineered. Responsibility is shared out among the supply chain under a performance-based system for the quality of concrete. Under a prescriptive system, the supplier or contractor can be held responsible for quality control issues. For the performance approach this has to be specifically defined, although systems are in place to help. Making it harder via ‘red tape’ for new products to enter a market may stifle innovation but it also gives these new products far more time to be tested rigorously.

The whole prescriptive-performance standards issue opens up the wider implications of decarbonising construction materials. Where once there was a relatively small number of different types of cement and concrete now there are potentially hundreds, each looking for market share. Whether this situation will be the same in a decade’s time remains to be seen. A few common SCM-based cement and concrete products and formulations may predominate. For now, the future seems wide open and bigger changes, such as the global performance-based standards Betolar is advocating, may be required to support this. Considering the massive variation between countries and states, even within the US and the European Union, let alone the rest of the world, this seems ambitious. But it is not impossible!

US: LafargeHolcim subsidiary LafargeHolcim US has adopted Environmental Product Declarations (EPD) to designate products’ Global Warming Potential (GWP) for easy consumer use, with third-party verification from ASTM International or the National Ready Mixed Concrete Association (NRMCA). Aggregates and construction materials chief executive officer (CEO) Jay Moreau said, “The growth in sustainable construction is driving demand for low-carbon building products that can transparently demonstrate a decrease in our environmental footprint. These new EPDs also push us to continue innovating as we consider the next generation of building materials.”

US: The Portland Cement Association (PCA) and other trade associations from the concrete and steel sector have urged that Larry Kudlow, the director of the National Economic Council, review the use of government funds on projects that use wood as a building material. The American Concrete Pumping Association, American Institute of Steel Construction, American Iron and Steel Institute, California Construction and Industrial Materials Association, Concrete Reinforcing Steel Institute, National Concrete Masonry Association, National Ready Mixed Concrete Association, Oregon Concrete & Aggregate Producers Association, Steel Framing Industry Association, Steel Manufacturers Association and the PCA expressed disappointment that the Department of Agriculture had awarded over US$8.9m for 29 projects designed to expand markets for wood products, particularly mass timber, for building construction.

The industry associations acknowledged the increase in cross laminated timber (CLT) projects in the US but they said they were concerned about the use of CLT on a large scale. They said that the grants unfairly promoted one building material at the expense of another.

UK: The Global Cement and Concrete Association (GCCA) has expanded its membership to 36 companies with its number of affiliates organisations rising to 15. The new members include Corporacion Moctezuma in Mexico, Unión Andina de Cementos (UNACEM) in Peru, JSW Cement in India and West China Cement in China.

The new affiliates include Oficemen (the Spanish Cement Association), the Cement Manufacturers Association of India, the Japan Cement Association, the National Ready Mixed Concrete Association in the US, the European Concrete Platform and the Federacion Iboamericana del Hormigon Premezclado (FIHP) which covers Latin America and the Iberian Peninsula

“The continuing and rapid growth of the association’s membership is very encouraging. With a strong work program now underway it’s important that our authoritative voice represents the growing list of cement and concrete manufacturers committed to our principles of enhancing industry sustainability efforts and driving innovation.” said GCCA chief executive officer (CEO) Benjamin Sporton.

The GCCA was launched in 2018. It aims to represent at least 50% of global cement production capacity.