Negative properties of concrete include the volume changes occurring during their solidification and hardening process.These deformations and cracks lead to reduce the strength and the durability of structures.The most important volume change of concrete is shrinkage resulting from the ongoing physical and chemical processes.The concrete with a high water to cement ratio is especially prone on the drying shrinkage.This article deals with the verification of the properties of cement mortars using selected kinds of plasticizing agents developed for self-levelling cement screeds.Applied agents(MS 3-12, MS 4-12, MS 5-12 and reference Berascreed 101)are based on modified polycarboxylates.The dosage of these agents was determined by the previous research in the amount of 1.5% by weight of the binder.The use of agents had a positive impact on the consistency of the fresh cement mortars and increased values of the initial and the long-term compressive strength.The negative impact of these agents was noted at the shrinkage and bulk densities of fresh and hardened cement mortars.Based on the achieved results can be concluded, that the plasticizing agent MS 4-12 may be considered a suitable substitute for the reference agent.
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机译：混凝土的阴性特性包括在其凝固过程中发生的体积变化和硬化过程。这些变形和裂缝导致结构的强度和耐久性。混凝土的最重要体积变化是由持续的物理和化学过程产生的收缩。混凝土具有高的水与水泥的比例是有关与使用所选种增塑剂的用于自流平水泥开发screeds.Applied剂水泥砂浆的性质的验证干燥shrinkage.This文章处理（MS 3-12特别容易， MS 4-12，MS 5-12和参考Berascreed 101）基于改性的多羧酸盐。这些试剂的剂量通过先前的研究确定的1.5％重量的粘合剂。使用剂的使用具有阳性对新鲜水泥砂浆的一致性和初始和长期抗压强度的增加的影响。这些agen的负面影响在新鲜和硬化水泥砂浆的收缩和散装密度处注意到TS。基于所达到的结果，可以得出结论，塑化剂MS 4-12可被认为是参考剂的合适替代品。
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