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Документ The efficiency of plasticizing surfactants in alkali-activated cement mortars and concretes(EDP Sciences, 2018) Runova, Raisa; Gots, Volodymyr; Rudenko, Igor; Konstantynovskyi, Oleksandr; Lastivka, Oles’Functionality of mortar and concrete mixes is regulated by surfactants, which act as plasticizers. The molecular structure of these admixtures can be changed during hydration of alkali-activated cements (AAC). The objective was to determine the chemical nature of plasticizers effective for property modification of mortars and concretes based on AACs with changing content of granulated blast furnace slag from 0 to 100 %. The admixtures without ester links become more effective than polyesters when content of alkaline component increase. The admixtures effective in high alkaline medium were used in dry mixes for anchoring (consistency of mortar 150 mm by Vicat cone; 1 d tensile strength in bending / compressive strength of mortar 6.6 /30.6 MPа) and in readymixed concretes (consistency class changed from S1 to S3, S4 with consistency safety during 60 min; 3 d compressive strength of modified concrete was not less than the reference one without admixtures).Документ Вплив мінеральних добавок на сульфатостійкість портландцементу(2019) Гоц, В. І.; Ковальчук, О. Ю.; Говдун, Я. О.Розглянуто ефективність підвищення сульфатостійкості цементів при використанні активних мінеральних добавок різного виду. Виявлено, що максимальний ефект підвищення сульфатостійкості спостерігається при використанні комбінації доменного гранульованого шлаку та золи-винесення в складі портландцементних систем, що супроводжується зростанням сульфатостійкості у 2 рази порівняно з контрольним складом. Отримано портландцементні системи з активними мінеральними добавками, сульфатостійкість яких не поступається традиційному сульфатостійкому шлакопортландцементу.Документ Radiation protective properties of fine-grained concretes and their radiation resistance(Харків: ХНУБА, 2020-05) Anopko, Dmitro; Honchar, Olha; Kochevykh, Maryna; Kushnierova, LiliaMany years of world experience in the selection of materials for radiation protection shows that concrete is the main material. It can combine heavy components to protect against gamma radiation and light components to absorb neutron fluxes. This fact, as well as manufacturability, low price and the possibility of using local materials, have determined the widespread use of concrete for protection against radioactive radiation.Документ The efficiency of plasticizing surfactants in alkali-activated cement mortars and concretes(Transbud-2018, 2018) Runova, Raisa; Gots, Volodymyr; Rudenko, Igor; Konstantynovskyi, Oleksandr; Lastivka, Oles’Functionality of mortar and concrete mixes is regulated by surfactants, which act as plasticizers. The molecular structure of these admixtures can be changed during hydration of alkali-activated cements (AAC). The objective was to determine the chemical nature of plasticizers effective for property modification of mortars and concretes based on AACs with changing content of granulated blast furnace slag from 0 to 100 %. The admixtures without ester links become more effective than polyesters when content of alkaline component increase. The admixtures effective in high alkaline medium were used in dry mixes for anchoring (consistency of mortar 150 mm by Vicat cone; 1 d tensile strength in bending / compressive strength of mortar 6.6 /30.6 MPа) and in readymixed concretes (consistency class changed from S1 to S3, S4 with consistency safety during 60 min; 3 d compressive strength of modified concrete was not less than the reference one without admixtures).Документ On Providing an Assessment Monitoring System for Especially Essential Structures(Trans Tech Publications, 2020) Kolokhov, Viktor; Kushnerova, Liliya; Moroz, Lina; Pavlenko, TetianaThe article deals with the assessment problems of especially essential structures. Increased demands on prevention of emergency situations and minimizing the consequences in the event of their occurrence require constant determination of especially essential structures condition. Achieving the goal of reliability and continuity of information is possible by coating the structure surface by a layer of electroconductive concrete, working as a monitoring system sensor. The study of the electrical properties of concrete was performed using the voltmeter – ammeter scheme. After the measurements had been made, the conditional electrical resistance of the electrode pair was calculated. The analysis of the above dependencies found that the change in the electrical resistance of the material from its stress approaches the linear law at lower values of W/C over a larger section of the studied interval. Processing of the obtained data showed that the measurement results were significantly affected by the shape and size of the electrodes used during the experiments.