MECHANISM FOR CREATING A CEMENT COMPOSITE WITH ENHANCED HYDROPHYSICAL AND RADIATION PROTECTION PROPERTIES

In modern conditions, the  environmental component of building  protective materials is guaranteed by the creation of composites capable of protecting underground and above-ground parts of buildings and  structures in flooded areas from the filtration of radiation-contaminated water, industrial wastewater, radon, etc. Therefore, the problem of developing modern, including radiation-protective materials for the construction industry is urgent. Concrete is a good  moderator and absorber of fast  neutrons and intensively absorbs gamma radiation. Concrete consists of  cement, sand and gravel. Cement consists mainly of oxides of various elements (Ca, Si, Al, Fe) and contains light elements. Portland cements, slag Portland cements and alumina  cements are used as binders for the preparation of particularly heavy  protective concrete. In special  concretes, the most effective binder  can be a substance that, as a result of hardening, adds a large amount of water (to increase the hydrogen content of the concrete). Such a substance is calcium  hydrosulfoaluminate. Recent studies have shown that very effective radiation protection materials are materials in the form of polydisperse systems containing ultrafine particles (UFP) less than 1 micron in size. However, the difficulty is to distribute the ultrafine particles evenly throughout the material volume, which dramatically reduces its protective functions.The work resulted in the development of a cement composite with enhanced hydrophysical and radiation protection properties, which were achieved by, firstly, modifying the cement binder  with chemical additives that facilitated the synthesis of crystalline hydrates with a high water content. Secondly, polydisperse systems in the form of ferruginous quartzite were added to the composition, where micron-sized iron particles were embedded in quartzite, which contributed to the uniform distribution of micron-sized iron particles in the volume of the composite. Physicochemical studies of cement stone hydration products were carried out by X-ray diffraction, differential thermal and electron microscopic analyses. The developed composition of fine-grained concrete has high  performance and hydrophysical  properties, provides protective properties against radiation due to components containing heavy and light atoms, which may allow the use of this material to protect building  structures, buildings and structures.