In this contribution is presented overview of aggregate from recycled concrete and steel making slag treatment in civil engineering industry. The goal of experiments is utilization of these wastes as the partial or complete replacement of natural aggregates fraction 4-8 and 8-16 mm in concrete. Partial replacement was carried out from 20 to 80 %.
Concrete structures and elements are often exposed to different aggressive environment. It leads to failures, cracking, weathering and deterioration of concrete materials. Under aggressive conditions, the concrete is liable to a corrosive process which is not usually caused by one specific factor but by combination of aggressive media. Sulphur environment is one of the most corrosive factors influencing the concrete durability.
The aim of this article is to present the results of preliminary research of the damping parameters of vibration in the constructions with the addition of zeolite. The first part of the article deals with the characteristics and application of zeolite. It describes mainly the impact of the addition of zeolite on the concrete parameters. The main part of the article presents the research outcomes of the damping parameters of the three models of plate-beam.
In this article concrete mixture composition with the additives of zeolitic tuff and superplasticizer was optimized by the method of mathematical planning of experiment. The research reveals that use of optimal amount of zeolitic tuff results in increasing strength of concrete at later age of hardening and does not influence significantly the water absorption, porosity and freezing temperature of the liquid phase of fresh frozen concrete mixture.
The article describes the effects of surface treatment of concrete protective coatings filled of polimetylfynilsyloksan based on its corrosion resistance. The influence of the coating on the adhesive strength, hydrophobicity and water absorption of concrete. The possibility of using the developed formulations of protective coatings to improve durability of concrete is showed, which is operated under conditions of external aggressive factors.
In the article physical and chemical analysis wasstudied the in fluence of zeolite-containing composite cement on the concrete hardening processes and its composition change sunderheating 1000 °С. The presence of blast furnace granulated slag and zeolite composite in cement increases the strength characteristics under heating to temperatures above 700 °С. This phenomenon occurs due to synthesis of fusible eutectics that fill the interstices, formed during clinker dehydration. As the result, the individual concrete pieces are being tied.
The article is devoted to development of theoretical foundations of improving corrosion resistance of concrete protective coatings based on filled with aluminum and zinc oxides polimetylfenilseloksanu. Methods of mathematical experiment planning with regard to water absorption depending on the concrete and coating adhesion strength optimum component of the original compositions for protective coatings, determined their technological and physical and mechanical properties, the thickness of the coating, application methods and the surface of the concrete conditions of the studied.
Розглянуто результати випробування бетонних кубів та призм на стиск з реєстрацією температури та сигналів тріщиноутворення акустичною емісією при руйнуванні зразків на пресі. Визначено можливість використання тепловізійного методу для технічної діагностики стану бетонних конструкцій.
***The results with registration temperature in the destruction of samples and crack acoustic emission signals of the test compression of concrete cubes and prisms presented on stand. The possibility of using thermal method for technical diagnostics of concrete structures shown.***