The paper considers a new BNTU development that is concrete complexes having modular-block design. The modular-block approach presupposes to divide the whole technological chain for production of concrete and mortar mixes into separate sections (modules), each of which performs specific functions and can be used separately and independently of others. Then it is necessary to select such set of modules that ensure production of concrete and mortars. The paper presents designs of main modules in the technological chain for preparation of concrete mixes: a concrete mixing module, a storage and supply module of inert materials, a storage and supply module of cement and a number of additional auxiliary modules (a concrete supply module, a module for preparation of chemical additives, an operator module and a module for preparation and supply of air).

Two main modifications of ready mix concrete stations developed on the basis of modular-block principle using basic modules are given in the paper. The first modification is a stationary concrete-mortar complex characterized by high productivity, large reserves of aggregates and cement, ability to be operated in winter due to heat insulation and water heating system and inert materials. The second modification is a transportable option that permits to transport the station from place to place due to reduction of time required for its installation and removal and execute production of concrete mixtures in the vicinity of the object construction. This options provides the possibility to reduce expenses on concrete transportation to the place of its deposit and decrease the probability of deterioration of consumer properties of the concrete mix that in its turn entails reduction in final cost of the object construction and improves quality of the construction.

Activation technologies of road construction materials considered in a single package represent an up-to-date progressively developing scientific and research direction in the transport material science. The essence of the activation technology for materials lies in an intensive increase of physical and chemical activity of their components in the interphase boundaries that is realized in various technological conversions. It has been established that being chemically passive under normal conditions all the materials, irrespective of their nature and aggregate state, can be chemically active under specific conditions. Such approach makes it possible to use low-active cheap silica raw material and technogenic production wastes for creation of strong composite materials on their basis.

Development of the activation technologies for solidand liquid –phase components of road construction composite materials is gradually transformed in a special branch of material science that is coprology. The branch is presupposed to develop a theory and solve applied problems directed on efficient usage of technogenic production wastes as cheap raw material source for obtaining a wide range of construction materials for general and special application. Further investigation is to execute a technical modernization and develop technological equipment for activation of solid, liquid and gaseous components of road construction composite materials. In this respect all technological solutions should serve for general purpose that is to ensure optimum structures of the obtained materials that provides their longevity with minimum resource expenses and maximum level of environmental protection.

One of the main ways to improve physical and mechanical properties of cement concrete is an introduction of ash obtained due to burning of fossil fuels into concrete mix. The concrete mixes with ash are characterized by high cohesion, less water gain and disintegration. At the same time the concrete has high strength, density, water resistance, resistance to sulfate corrosion. The aim of this paper is to explore the possibility to use peat ash and slag of peat enterprises of the Republic of Belarus in the concrete for improvement of its physical and mechanical properties and characteristics of peat ash, slag, micro-silica, cement, superplasticizing agent. Compositions and technology for preparation of concrete mixes have been developed and concrete samples have been have been fabricated and tested in the paper. It has been shown that the concrete containing ash, slag obtained due to burning of peat in the industrial installations of the Usiazhsky and Lidsky Peat Briquette Plants and also MK-85-grade micro-silica NSPKSAUsF-1-grade superplasticizing agent have concrete tensile strength within 78–134 MPa under axial compression and 53 MPa – for the control composition. This index is 1.5–2.5 times more than for the sample containing no additives.

The usage of peat ash, slag together with MK-85-grade micro-silica and NSPKSAUsF-1-grade superplasticizing agent for fabrication of concrete and reinforced bridge and tunnel structures will provide the following advantages: reduction of cross-sectional area of structures while maintaining their bearing capacity due to higher value of tensile strength in case of axial compression; higher density, waterand gas tightness due to low water cement ratio; high resistance to aggressive environment due to lower content of capillary pores that ensures bridge structure longevity; achievement of environmental and social impacts.

Real assessment of wear in technical devices, construction structures, minings, their elements and connections is of great importance for provision of operational security and efficiency. Natural properties of the overwhelming majority of materials follow to probabilistic (stochastic) laws due to various reasons (external influence, processing technologies and others). An assessment of physical wear rate of buildings and structures and their elements is carried out in the former republics of the USSR mainly in accordance with external physical signs (deflections, cracks, layer separations, etc.) but wear percentage is often calculated on the basis of replacement cost in comparison with the initial one even without taking into account inflation which did not officially exist in the USSR. In this case destruction or failure of structure or their elements are considered as 100 % wear.

The paper proposes a new methodology for assessment of physical wear rate in accordance with probability ratio of nofailure operation (reliability), minimum ratio is assigned to admissible limit value in conformity with technical requirements for the technical devices, construction structures, minings in question, their elements and connections. In this context minimum permissible wear probability (reliability) is taken as 100 % wear rate and its initial index is considered as 0 % wear rate. That is why wear intensity in time depends on type of value probability distribution while determining the rate of physical property. The proposed methodology is intended for probabilistic wear assessment in case of relatively simple changes in strength properties of materials (for example, within the elastic limit).

The paper presents results of investigations on influence of domestic complex chemical additive containing structured carbon nanomaterial and characterized by a combination effect (curing acceleration and plasticizing) on cement and cement stone properties. The purpose of the investigations, on the one hand, has been to confirm efficacy of УКД-1additive from the perspective for increasing the rate of gain, strength growth of cement concrete and additive influence on setting time with the purpose to preserve molding properties of concrete mixes in time, and on the other hand, that is to assess “mechanism” of the УКД-1 additive action in the cement concrete. The research results have revealed regularities in changes due to the additive of water requirements and time period of the cement setting. The reqularities are considered as a pre-requisite for relevant changes in molding properties of the concrete mixes. The paper also experimentally substantiates the possibility to decrease temperature of cement concrete heating with the УДК-1 additive. It has been done with the purpose to save energy resources under production conditions. In addition to this the paper proves the efficiency of the additive which is expressed in strength increase of cement stone up to 20–40 % in the rated age (28 days) that is considered as a basis for strength growth of cement concrete. The paper confirms a hypothesis on physical nature of this phenomenon because the X-ray phase analysis method has shown that there are no changes in morphology of portland cement hydration products under the action of the additive agent containing a structured carbon nanomaterial. Results of theoretical and experimental investigations on УКД-1 additive efficiency have been proved by industrial approbation while fabricating precast concrete products and construction of monolithic structures under plant industrial conditions (Minsk, SS “Stroyprogress” JSC MAPID) and on building sites (Mogilev, JSC Stroytrest No 12).

Floor-by-floor survey of installed elements of an elevator shaft using coordinate method and tacheometer is also inhibited by the necessity to determine device installation points for floors of every mounting horizon that leads to additional measurements due to conditions of the completed building framework and presence of a great number of situational disturbances and then it entails significant time expenditure and diminution of accuracy in the obtained results. Technical capabilities of the modern electronic tacheometer substantially simplify an accomplishment of the mission because the device can be applied not only in function of vertical projection but it can be used for preand post-construction survey of the elevator shaft with the help of advanced radiation method. While using the given method the electronic tacheometer equipped with diagonal ocular is installed over a bearing sign in the elevator pit and control points of the elevator shaft are determined with the help of specially developed portable beam deflector in the form of disc with radius r, which is fixed to a handle rod and orientated perpendicularly to a laser beam. An innovation diagram for preand post-construction survey of elevator shaft has been developed while applying this type of deflector. The diagram is characterized by high efficiency due to the fact that one tacheometer installation makes it possible to execute highly accurate, complete plane and high-level surveying of the whole elevator shaft including doorways, door sills and jambs.

The paper proposes a new method for pre and post construction survey of the elevator shaft using the electronic tacheometer while applying specially developed beam deflector that ensures a geometric fixing of one or simultaneously two surveying points to spatial coordinate system where the preand post-construction survey is carried out. The method is characterized by high geometric accuracy and technological efficiency.

Modern tendencies for assessment of high-rise building deformation state presuppose creation of automated and regular monitoring while using highly-accurate space positioning systems (GPS-systems), a robotic electronic tacheometer, highlyaccurate inclinators (Leica Nivel210/Nivel220-model) with measuring accuracy of tilt angle up to 0.09 s, Geomos software complex (Leica Geosystems). Automated system for deformation monitoring requires significant time and material expenditures, special training of specialists so simpler methods and criteria for assessment of building deformation state are also considered as rather actual for this purpose.

There are more than ten conventional methods for determining building tilt. All these methods are based on angular measurements from the fixed base while using highly-accurate theodolites. The methods are rather labor-consuming and they do not provide operational efficiency and accuracy in measurements. Introduction of electronic tacheometers with large radius of refractorless measurements of distances has made it possible to calculate coordinates on the building surface with high accuracy and at various sections (heights) that results in possibility to obtain 3D model of the building surface. Leica TCRA1201 tacheometer has been set at the good visibility point of a tower construction, device orientation and plane coordinates of the temporary point have been determined with the purpose to assess a tilt value of an exhaust stack having 150 meter height. Then 3D coordinates of six points on the building surface have been measured for every stack section. After that these points have been projected on the horizontal plane. LISCAD PLUS software complex has been used for processing and interpretation of geodetic data.

The proposed method permits to obtain data for determination value and direction of a tower construction tilt, immediately carry out in-situ measurements and obtain final results in the automatic mode of LISCAD PLUS software complex using only one point of the tacheometer setting. The method does not require any preliminary laying and subsequent preservation of fundamental geodetic points (bases) and it can be applied for any configuration of tower constructions.

The paper presents constructional and technological features for manufacturing driven piles with variable strength of pile shaft. Economical efficiency of their production has been shown in the paper. The paper provides a pile cap design that ensures perception of hammer impacts with the help of lateral edges of the pile cap. Driven reinforced concrete piles which are manufactured from three shaft sections having various strength have been proposed in the paper. Material strength (concrete grade and diameter of bars) and length of shaft sections are given on a case by case basis in accordance with nature and rate of stresses in piles during their driving process. Manufacturing of polystrong piles provides an opportunity to select them for a particular construction site with due account of their preservation during driving process.

A pile cap has been developed that as opposed to existing analogous designs makes it possible to transmit impact efforts from a hammer to the pile through lateral surface of its head part. The pile cap provides the possibility to increase an area for perception of hammer impact efforts by the pile and in doing so it is possible significantly to reduce a damage risk and destruction of pile concrete during its driving. Application of polystrong piles and their driving with the help of new pile cap are considered as a basis for defect-free and resource-saving technology for pile foundations in the construction.

The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.

In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa). The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.

The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality change on purification phases with various filtration rate have been determined in the paper.

Эффективное использование водохозяйственного комплекса является необходимостью многих стран мира, особенно развивающихся, как Вьетнам. Во Вьетнаме одной из отраслей с высокой потребностью в воде и большим изменением ее расхода в течение года является орошение сельскохозяйственных культур, в основном риса. Потребность в воде на нужды орошения зависит не только от культур, климата, но и от выпадающих осадков. Но такими осадками невозможно управлять. Однако выпадающие осадки, в свою очередь, формируют речной сток, а стоком рек управлять можно с помощью его регулирования (создания водохранилищ). Поэтому важно знать, каким образом величина речного стока связана с потребностями в воде на орошение.

Рассмотрены связи между режимом орошения и режимом речного стока, что особенно актуально для бассейнов рек предгорных районов Вьетнама, где в течение года собирают два-три урожая, а сток рек в различные вегетационные периоды может существенно (до 10 и более раз) отличаться. Эта связь формируется на основе отношений между потребностями в воде орошения и количеством осадков, между количеством осадков и речным стоком в бассейне. Отношение между потребностью в воде орошения (полив нормы) и речным стоком (слой стока) в бассейне является одним из результатов расчетов, необходимых для оптимизации параметров и режимов работы водохозяйственного комплекса в бассейнах малых рек предгорных районов Вьетнама.

In recent time piled foundations are extensively applied due to an increase of storeys in buildings constructed in Minsk and load increment on the soil. Preference is given to this approach even in the case when relatively firm soil occurs in the top part of the foundation bed. In this case maximum usage of the foundation bed bearing capacity and reduction of foundation cost are considered as top-priority tasks for designers. One of the ways to increase the bearing capacity of piled foundations is the necessity to take into account resistance of foundation bed soil located under raft bottom. The raft as well as a shallow foundation is capable to transfer a significant part of building load into the soil. Such approach makes it possible to reduce a number of piles in the foundation or shorten their length. Then it results in shortening of the construction period and significant reduction in zero cycle. However up to the present moment reliable calculation methods that permit to take into account soil resistance in the raft base. An analysis of previous investigations on the matter executed by various researchers and a number of field investigations have been carried out with the purpose to develop the proposed methods.

The paper presents results of field investigations on foundations consisting of short stamped tapered piles which are joined together with the help of the raft fragment. Strength and deformation characteristics of the bases are increasing while making such foundations in the fill-up soil. In this case the filled-up ground layer becomes a bearing layer both for piles and rafts as well. Improvement of high-plastic clay-bearing soil properties is ensured by ramming dry concrete mix under pile foot. The paper describes an experience on application of the piled-raft foundation in complicated engineering and geological conditions while constructing the Orthodox Church in Minsk.

The paper considers main advantages and disadvantages of mobile mortar concrete plants in comparison with stationary concrete mixing units. The main idea of the mobility is to provide quick movement. In its turn, this approach imposes some restrictions on dimensions and weights of concrete mixing equipment. However in the context of the concrete mixing equipment and construction site as whole the mobility concept is considered in the form of three components: minimum expenses on site preparation for assembly of a mortar concrete plant, transportability, reduction in installation and startand-adjustment periods. In this regard processing chain for production of concrete and mortar mixes is divided in separate complete operations. Then it is necessary to develop modules which are performing the required operations. Every module is developed in accordance with the size of a shipping container in order to make transportation convenient. Detachable connections are stipulated in the place of module linkages, electrical wiring, pipelines for supply water and chemical admixtures, pneumatics. Henceforth, these connections make it possible to reduce time for on-site assembly and disassembly of the equipment.

The paper presents a mobile mortar concrete unit of block-module arrangement which has been developed within the framework of the State Scientific Research Programme at the BNTU. The unit has been manufactured using production capacities of JSC “Viprotekh” and it has been successfully introduced in production process. One of the promising directions is to use the mobile mortar concrete plants which are located and which are operating directly on construction sites. Their economic efficiency becomes higher with an increase of distance to the nearest stationary mortar concrete unit and scope of concreting works. Mobile mortar concrete plants are mainly intended for construction organizations which are realizing construction projects away from urban infrastructure and transportation networks: bridges, dams, highways, transport junctions. While ensuring the same production output of concrete these plants are located in close proximity to the construction site and the required mortars can be supplied directly to the site with the help of special concrete pumps.

The paper proposes a technology for obtaining bricks on the basis of lime-silica mixtures where chemical interactions are practically completely realized in dispersive state at the stage of preparation of binding contact maturing and raw mixture as a whole. The role of forming operation (moulding) is changed in principle because in this case conversion of dispersive system into a rock-like solid occurs and due to this the solid obtains complete water-resistance in contact with water immediately after forming operation. Theoretical basis for the developed technology is capability of silicate dispersive substances (hydrated calcium silicate) to transit in non-stable state, to form a rock-like water-resistant solid in the moment of mechanical load application during forming process. Specific feature of the proposed method is an exclusion of additional operations for autoclaving of products from the process of obtaining a silicate brick.

Synthetic hydrated calcium silicate in contrast to natural ones are more uniform in composition and structure, they contain less impurities and they are characterized by dispersive composition and due to the mentioned advantages they find wider practical application. Contact-condensation binders permit to manipulate product properties on their basis and ensure maximum correspondence to the requirements of the concrete application. Raw material sources for obtaining synthetic hydrated calcium silicates are practically un-limited because calcium-silicon containing substances are found as in various technogenic wastes so in natural compounds as well. So the problem for obtaining hydrated calcium silicates having contact-condensation ability for structure formation becomes more and more actual one. This transition is considered as dependent principally on arrangement rate of substance particles which determined the level of its instability.