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CONCRETE TECHNOLOGY22 CPI %u2013 Concrete Plant International | India Edition %u2013 6 | 2025 www.cpi-worldwide.comDiscussionAlthough the clays used in this study were ground to have similar particle size distribution, their SSAs were very different, indicating that the clays have different properties, and the kaolinite content is not the only factor to consider when assessing their suitability for producing LC3 concrete. For example, although HC-Clay has a kaolinite content of about 40%, its SSA is very high (37 m%u00b2/g). This demanded higher amounts of water or dosage of SP, which is not practical for most structural applications where satisfactory workability and setting time is usually required to produce high quality concrete. However, the mix can potentially be used for %u2018dry%u2019 mix applications such as brick and block making with mechanical compaction, such as in precast and factory applications. Roller-compacted concrete could be another application.As evidenced by the compressive strength results, the early age strength gain of the LC3 mixes with 55% and 65% clinker, especially with B-Clay, PH-Clay, and HC-Clay, is similar to or better than that of the reference mixes. These binder systems react strongly during the first few days, overcoming the main problem of most binary mixes with slow early strength gain. Even in the case of the slow strength gain of the LC3(H) mixes, the performance is similar to or better than the reference mix R2.Results also show that the rate of later strength gain does not necessarily depend on clinker content of the mix, as the required minimum amount of clinker for optimum strength performance depends on the amount of calcined kaolinite in the clay.The factors affecting drying shrinkage in concrete are well explained in the literature. In this case, it is important to note that in all these mixes, the amount of water, amount of stone and the total amount of binder were fixed at 160 kg/m%u00b3, 1000 kg/m%u00b3, and 400 kg/m%u00b3, respectively. Therefore, it is only the w/b ratio, type of binder and/or the proportion of binders that controlled drying shrinkage of the specimens.In general, the LC3 mixes, especially with B-Clay and PH-Clay, have lower shrinkage strain, almost 50% lower compared to reference mix R1. Presumably, with higher ISA there is more %u2018bound water%u2019 initially that can be slowly released back into the matrix with time as in the case of lightweight aggregates.Comparing the results of the two cases, 0.4 w/b ratio and 0.55 w/b ratio, the shrinkage strain for the reference mix R1 increases moving from a w/b ratio of 0.4 to a w/b ratio of 0.55. This was expected, since increasing the w/b ratio leads to increasing the amount of evaporable water, and thus an increase in shrinkage strains. Surprisingly, it is different in the case of LC3-55(B) and LC3-55(H) where the shrinkage strain appears to reduce going from a w/b ratio of 0.4 to a w/b ratio of 0.55. The reason for this is not yet clear, but most likely can be related to the high ISA of the clays and therefore how much water was available initially to react in the system, something that need further research. For elastic modulus, results show that the performance of the LC3 mixes is similar to that of the reference mixes. This indicates that the LC3 systems, like other conventional systems, do not affect the elastic modulus of concrete. ConclusionsBased on the results presented in this paper, the following can be concluded with respect to the compressive strength and deformation behaviour of the LC3 concretes that were studied:%u2022 For the LC3 mixes, the demand of SP dosage depends mainly on the specific surface area (SSA) of the respective clay.%u2022 LC3 systems react strongly during the first few days compared to most binary mixes where the main problem is the slow gain of strength at early ages, which usually restricts the effective application of these systems in construction. Thus, especially for precast production, the use of LC3 cement offers practical solutions for the production of concrete with improved sustainability characteristics. %u2022 Apart from kaolinite content, the amount of calcined clay in the system, and the filler effect, the compressive strength performance of the LC3 concretes also appears to depend on the SSA of the clay and the alkali level in the system. %u2022 Different LC3 systems, regardless of the clinker content and type of clay, minimally affect the elastic modulus of concrete, compared to concrete produced with conventional cement types.%u2022 LC3 mixes produce lower drying shrinkage strain than a mix with 100% conventional CEM II/A-L or a mix with 50% of CEM II replaced by GGBS, provided that the Na2Oeq in the system is not high. The durability properties of the concrete systems discussed in this paper will be covered in a follow-up publication in the next issue of CPI. www.cpi-worldwide.comCONCRETE TECHNOLOGY CONCRETE TECHNOLOGY96 CPI %u2013 Concrete Plant International %u2013 2 | 2025 www.cpi-worldwide.com www.cpi-worldwide.com CPI %u2013 Concrete Plant International %u2013 2 | 2025 97Kraft Curing Systems is proud to be a technology leader in concrete curing. As a team dedicated to innovation, they are excited to share their latest advancements, including the Match-Cure System with Predictive Maturity, the E-Cure System, and the CO2 TestCube. Additionally, as Kraft Curing Systems prepares for bauma 2025, they look forward to showcasing their cutting-edge solutions, alongside the expansion of their operations with the new Logistics and Competence Center at the headquarters in Lindern, Ger- many, set to break ground in summer 2025.Expanding for the Future Beyond product innovations, Kraft Curing Systems is making a significant investment in their future with the construction of a new Logistics and Competence Center, set to start in summer 2025. This facility will serve as a central hub for logistics, production, and technical innovation, allowing for expanded capabilities and the development of curing solutions such as the patented and one-of-a-kind Kraft%u00ae Racks. The new Competence Center will also provide hands-on technical training and workshops, reinforcing the dedication to knowledge-sharing and industry education. This expansion will enable Kraft Curing Systems to not only increase their production capacity but also strengthen their ability to sup- port customers worldwide with advanced solutions and ex- pert guidance.Concrete Curing Innovations One of the most exciting recent breakthroughs is the Match- Cure System with Predictive Maturity Control, designed to provide real-time data on concrete strength development. This system allows manufacturers to optimize their production processes, reduce curing times, and improve overall efficiency by predicting the maturity and performance of concrete with unparalleled accuracy. Predictive maturity control enables users to set necessary strength and allotted time, automatically allowing the system to determine the best curing process.Match-Cure with Predictive Maturity Control provides real-time curing monitoring, allowing users to track concrete strength gain as it occurs. It enhances precise production planning by forecasting the exact time for detensioning or demolding, eliminating guesswork, and reducing errors. The system automatically adjusts the curing profile based on the required maturity and strength, ensuring consistent results. By implementing Predictive Maturity, manufacturers can benefit from quick reaction alerts if curing is delayed, allowing them to make immediate adjustments. This system also helps save time and personnel costs by enabling production teams to plan more efficiently, ensuring workers are availa- ble precisely when needed. Additionally, energy savings are Pioneering Innovation in Concrete Curing Kraft Curing Systems GmbH, 49699 Lindern, Germanyachieved by avoiding unnecessary heating and curing durations, significantly lowering operational expenses.Another significant advancement is the E-Cure System. This electric-powered curing system provides consistent and controlled heating, accelerating the curing process while reducing energy costs. With radiant heating units placed under- neath molds, beds, or forms, E-Cure ensures uniform curing without the need for fossil fuels, making it both an effective and sustainable solution for concrete production.In line with the commitment to sustainability, Kraft Curing Systems introduced the CO2 TestCube, a test chamber that eval- uates the sequestration potential of CO2 in concrete prod- ucts. The TestCube also enables users to test with heat and humidity, paving the way for a more sustainable future in the industry. This innovative tool allows manufacturers to assess how CO2 can enhance strength and quality, reduce carbon footprints, and contribute to more environmentally friendly building practices.The Pulse of Innovation on Display at bauma 2025 The Kraft team is looking forward to connecting with custom- ers, partners, and industry professionals at bauma, showcasing a range of solutions. One of the key highlights at booth 12.9 will be the aforementioned Match-Cure with Predictive Maturity, an advanced system that takes quality control to the next level by automatically determining the optimal curing process for the earliest possible detensioning and demolding. Visitors will also be able to see the Retractable Enclosures with Vapor Curing, which provide an economical and weath- erproof solution while integrating vapor curing and air circulation systems to ensure optimal curing conditions.Another highlight is the Containerized ThermalCure%u00ae, a pre-plumbed and pre-wired system that accelerates curing through radiant heat emitted from fin-tube pipes For those looking to experience an optimized curing climate firsthand, the operational Kraft%u00ae Racks Curing Chamber will be available at booth b12.2, allowing visitors to step inside and witness the patented curing system in action. Kraft Curing Systems will also showcase real-world applications of their curing technologies through a series of %u201cCuring Systems in Action%u201d videos, illustrating how their solutions fit into differ- ent concrete production processes at booth b2.150 between halls b1 and b2.Beyond these technological advancements, Kraft Curing Systems will highlight their commitment to sustainability with CO2 curing. Additionally, the renewable energy solutions will be on display, featuring high-efficiency stainless steel heat exchangers that recycle warm air, cut heating costs by up to 75%, and provide enhanced humidity control.A Commitment to Excellence %u201cAt Kraft Curing Systems, we are committed to pushing the boundaries of curing technology while supporting our customers with the best solutions available,%u201d said Michael Kraft. %u201cWith our latest innovations and the expansion of our operations, we are excited to shape the future of concrete curing. As Bauma 2025 approaches and the Logistics and Competence Center nears its groundbreaking, we remain at the forefront of the industry, driving progress and setting new standards in concrete curing technology.%u201d nFURTHER INFORMATIONKraft Curing Systems GmbH M%u00fchlenberg 2, 49699 Lindern, Germany T +49 5957 96120 info@kraftcuring.comwww.kraftcuring.comStand B2.150, Stand B12.2, Stand B12.9Site of the future expansion of the Kraft Curing Headquarters.The predictive maturity control option for the Match-Cure Quality Control System allows producers to decide when the product is ready for demoulding or detensioning.A retractable enclosure with integrated vapor curing in action.A look back at booth 12.2 at the 2022 bauma.2 www.cpi-worldwide.com2025Concrete Plant International Worldwide English EditionBAUMA 2025 %u2013 NEWS +++ BAUMA 2025 %u2013 NEWS +++ BAUMA 2025 %u2013 NEWS +++ BAUMA 2025 %u2013 NEWS CONCRETE TECHNOLOGY Wireless embedded sensor for monitoring internal relative humidity in concrete CONCRETE PRODUCTS New control concepts to increase effi ciency in concrete block and paver production PRECAST CONCRETE ELEMENTS Flexible transformer substation moulds in demand in Europe MIXED AND COMPACTED Concrete barrel instead of barrique barrelRATEC MOULDS TURN BETTER IDEAS INTO SERIES PRODUCTIONWhen it comes to smart 3D mould solutions for precast concrete production %u2013 think of us. BETTER IDEAS %u2013 Made in Germany! >> www.ratec.org Visit us at Hall B1, Stand 348 April 7 %u2013 13, 2025 I Munich2502_cpi_U1-4_en.indd 1 28.02.25 12:05SUBSCRIPTION