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CONCRETE TECHNOLOGYCPI %u2013 Concrete Plant International %u2013 6 | 2025 www.cpi-worldwide.comAs 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 HCClay, 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. CONCRETE PLANTINTERNATIONALTRADE JOURNALS FOR THE CONCRETE INDUSTRYAsk me a question.Hello, i%u00b4m CPi Chat!What is recycled concrete?Recycled concrete aggregates (RCA) are concrete waste that can be classified as fine recycled concrete aggregates (fRCA) and coarse recycled concrete aggregates (cRCA). RCA is typically free of masonry or brick components of construction and demolition waste (C&DW), as these materials have porous microstructures that significantly affect the properties of RCA [1]. RCA can be simplified as a two-phase composite material...This link will take you directly to the article:%u2022 [1] The use of recycled aggregates to produce concrete productsHello, i%u00b4mthe AI chatbot from CPI worldwide for the precast concrete industryI%u2018m an intelligent search engine and expert in all CPI contents. You can ask me questions and talk to me. I%u2018ll use our knowledge database to give you specific answers to this and all other CPI articles. www.cpi-worldwide.comTest the CPI Chat and visit our website: