Concrete paving slabs for road construction are made from mixtures consisting of hydraulic binder, fine and coarse aggregates and water. The prepared mixture of a given humidity is subjected to vibration molding under the following technological conditions: process duration 5–10 seconds, vibration frequency 30–50 Hz and pressure 70–80 kg/cm2. Hardening of freshly molded samples is carried out in a heat and humidity treatment chamber. It has been established that it is possible to replace natural coarse aggregate with fractionated scrap concrete. The compressive strength of concrete with aggregate based on recycled crushed stone is 300 - 400 kg/cm2, water absorption 4.8 - 6.2%, frost resistance F2 200 - 300. The proposed technology allows solving both economic and environmental issues for regions with large amounts of concrete scrap at temporary industrial waste storage sites.

Keywords: concrete mixture, vibroforming, modifiers, filler, waste, concrete scrap, strength

Porous concrete is a new type of concrete with high permeability of water flows. It is advisable to use this type of concrete in road construction for the device filtration zones. This will allow to remove water from the carriageway, especially in places where there is no storm sewer. Infiltration of water flows through concrete pavement coatings contributes to their rapid removal from the surface, reducing slipperiness and water planning. The use of macroporous concrete will minimize flooding of car parks and roads. The results of the study confirm that permeable concrete surfaces function stably over time and are not silted with sand and soil.

Keywords: porous concrete, permeable surface, filtration, storm sewage, water

Up to now, the problem of recognizing printed characters of different fonts with high speed and reliability is not solved. The team of authors carried out research of images of printed characters of different fonts for the purpose of revealing the signs necessary and sufficient for recognition of signs by a computer. These features were a certain combination of directions, formed by elements of the contours of signs. According to the developed program for the computer, the image of each printed character stored in the computer's memory device was scaled up, uncharacteristic signs of signs, certain defects were eliminated and the contour of the sign was highlighted. The contour was represented in the form of a sequence of definite directions formed by its elements. All printed characters of the Russian alphabet of different fonts were recognized by a certain technique, despite the different types of printed fonts, for certain possible defects.

Keywords: printed sign, direction, standard view, recognition, outline, font, tag, serif, reading device, information

Investigations were conducted to assess the corrosion resistance of stabilized sandy loam soil with ground granulated slags in organic media: mineral oil, gasoline and diesel fuel. A model is proposed for an accelerated study of the corrosion resistance of concretes and other building materials under the conditions of the dynamic effect of the medium under investigation on the test material. The obtained results of X-ray phase analysis of samples and electron microscopic studies suggest that as a result of hydration of minerals of ground slag and ground, low-base CSH (B) hydrosilicates are formed, the sizes of new formations and inclusions on ETF slag are less than on CMP slag.

Keywords: ground granulated slags, low-basic formations, corrosion resistance, slag-alkali binder, oil, porosity, dynamic model