Research on the technology of constructing a protection with joint use of no-fines concrete and bitumen

To build a bank slope protection of a hydraulic structure, a technology is proposed that involves building a framework of no-fines concrete and pouring it with hot bituminous materials. Implementation of this technology requires conducting a research on bitumen penetration into the protection plate body. The research involved developing models of non-stationary filtration under varied bitumen viscosity. The research involved experimental observation in laboratory environment. Models of movement of a variable viscosity liquid in a porous medium were proposed, and their study in laboratory environment allowed for identifying the depth of penetration, which is an important result to solve engineering objectives

Efficiency of construction waste recycling

Recycling is widely used in practice in various fields of activity. However, the effect of such use does not always cover the costs of the processing. The article considers the problem of recycling waste generated while constructing residential buildings and structures. We present the results of full-scale studies of construction waste generated at construction sites in the city of Samara. We also show the qualitative and quantitative composition of the elements and analyze possible ways of their reuse. In addition, we have calculated economic feasibility of reusing building materials recycled from construction waste

Modified composite material developed on the basis of no-fines asphalt concrete

Being a composite material, asphalt concrete is widely used in hydraulic engineering and road construction. The paper proves one of asphalt concrete modification, which includes first creating a skeleton of no-fines concrete and then its washing-down with bituminous materials by a hot procedure, can be successfully used in hydraulic structures Modified composite material based on no-fines asphalt concrete has a harder skeleton because of links from cement stone and has a technological advantage, as through the proposed technology it allows to reduce the cost of filling porous spaces. This technology allows to conclude that concrete aggregate with size fractions of 120 mm or less and frost resistance of 50 cycles and less can be recommended for fastening of slopes

Efficiency of construction waste recycling

Recycling is widely used in practice in various fields of activity. However, the effect of such use does not always cover the costs of the processing. The article considers the problem of recycling waste generated while constructing residential buildings and structures. We present the results of full-scale studies of construction waste generated at construction sites in the city of Samara. We also show the qualitative and quantitative composition of the elements and analyze possible ways of their reuse. In addition, we have calculated economic feasibility of reusing building materials recycled from construction waste

The possibility of using materials based on secondary gravel in civil construction

By now, the wear and tear of housing stock is more than 50%. Each year the number of old and dilapidated housing is growing, but it is gradually replaced by modern buildings. However, wastes accumulated from dismantling of buildings and constructions, are underutilized and, usually are just stored at landfills, or used for temporary roads construction. The purpose of this research is to define construction wastes characteristics and to explore possibilities for recycling of wastes from construction materials production. The paper also analyzes housing stock condition and basic requirements to building materials used in construction; and demonstrates results building materials based on secondary gravel investigation. While working with materials based on waste requirements the authors conducted laboratory research. Thus, the paper presents the analysis of laboratory tests results that made it possible to draw conclusions about the possible use of building materials based on secondary gravel and about their conformity to specified requirements. The researchers also developed proposals and recommendations to improve the competitiveness of such materials

The possibility of using materials based on secondary gravel in civil construction

By now, the wear and tear of housing stock is more than 50%. Each year the number of old and dilapidated housing is growing, but it is gradually replaced by modern buildings. However, wastes accumulated from dismantling of buildings and constructions, are underutilized and, usually are just stored at landfills, or used for temporary roads construction. The purpose of this research is to define construction wastes characteristics and to explore possibilities for recycling of wastes from construction materials production. The paper also analyzes housing stock condition and basic requirements to building materials used in construction; and demonstrates results building materials based on secondary gravel investigation. While working with materials based on waste requirements the authors conducted laboratory research. Thus, the paper presents the analysis of laboratory tests results that made it possible to draw conclusions about the possible use of building materials based on secondary gravel and about their conformity to specified requirements. The researchers also developed proposals and recommendations to improve the competitiveness of such materials

Modified composite material developed on the basis of no-fines asphalt concrete

Being a composite material, asphalt concrete is widely used in hydraulic engineering and road construction. The paper proves one of asphalt concrete modification, which includes first creating a skeleton of no-fines concrete and then its washing-down with bituminous materials by a hot procedure, can be successfully used in hydraulic structures Modified composite material based on no-fines asphalt concrete has a harder skeleton because of links from cement stone and has a technological advantage, as through the proposed technology it allows to reduce the cost of filling porous spaces. This technology allows to conclude that concrete aggregate with size fractions of 120 mm or less and frost resistance of 50 cycles and less can be recommended for fastening of slopes

Stand-by spillways in phreatic dams

Hydraulic structures operation is always connected with accident risks. The authors analyzed emergency situations which affected dams located on the territory of the USA and Russia. This analysis showed that the most dangerous accident which took place at hydroelectric complexes is an overfall through the crest of the dam accompanied with the formation of washouts and blow-out waves. The most striking example here is the accident at St. Francis dam. According to most researchers, its main cause was the human factor. To reduce economic losses which are due to an accident on the hydro-technical construction and to reduce the risk of human influence, the authors propose to use a stand-by spillway in the body of a phreatic dam. For this purpose, they introduce two constructions. The first construction has a melting insert and a spillway channel fastening made of synthetic materials. The second one has filtering covering of a crest and a downstream slope made of coarse-pored concrete. The researchers perform physical and numerical modeling of the developed structures to compare them. On the basis of laboratory experiments and calculations in the program complex, they obtain discharge coefficient values for various spillways, which can be later used for calculating spillway capacity as well as for its construction

Stand-by spillways in phreatic dams

Hydraulic structures operation is always connected with accident risks. The authors analyzed emergency situations which affected dams located on the territory of the USA and Russia. This analysis showed that the most dangerous accident which took place at hydroelectric complexes is an overfall through the crest of the dam accompanied with the formation of washouts and blow-out waves. The most striking example here is the accident at St. Francis dam. According to most researchers, its main cause was the human factor. To reduce economic losses which are due to an accident on the hydro-technical construction and to reduce the risk of human influence, the authors propose to use a stand-by spillway in the body of a phreatic dam. For this purpose, they introduce two constructions. The first construction has a melting insert and a spillway channel fastening made of synthetic materials. The second one has filtering covering of a crest and a downstream slope made of coarse-pored concrete. The researchers perform physical and numerical modeling of the developed structures to compare them. On the basis of laboratory experiments and calculations in the program complex, they obtain discharge coefficient values for various spillways, which can be later used for calculating spillway capacity as well as for its construction

Algorithm development of structural variables for slope reinforcement of hydrotechnic structures with synthetic materials

The construction of hydrotechnic structures out of watercourse area is usually done with grass seeding above a vegetative soil layer. For stability of slope protection, during and after construction, it is suggested that vegetated soil is reinforced with cubic geosynthetic mats. To choose a geosynthetic material the algorithm is offered, taking into account conditions that provide resistance of vegetated soil layer, and depending on forces that act upon the slope and considering changes of material properties in course of time technological peculiarities of its placement