Application of fibro concrete mixture at construction of bases and coatings automobile roads

Abstract

Fiber concrete – concrete with the inclusion of fibers (fibers) from inorganic or organic materials (steel, glass, polyethylene, etc.). Fiber concrete reinforced with fibers, has a high resistance to shock loads and abrasion, well perceives tensile stresses. An important issue in the preparation of fiber-reinforced concrete is its mobility. One of the difficulties encountered in practice when working with fiber reinforced concrete, reinforced by steel wire, is its lack of workability. To ensure the required workability of the concrete mixture and to achieve a uniform distribution of wire segments in it, it is necessary, in addition to the wire segments and the core, to control their ratio. Tests of fiber reinforced concrete showed that the larger the aggregate size, the lower the flexural strength. The use of granite crushed stone with a size of 20 mm allows to obtain better results than when using crushed stone from gravel or limestone. While in ordinary concrete, the quality of rubble increases the flexural strength, in fibrous concrete, the flexural strength increases the effectiveness of the fibers. The use of fiber-reinforced concrete in the construction of road pavements is determined by technical and economic efficiency, which is caused by the most complete use of the positive properties of fiber-reinforced concrete as compared to conventional cement concrete. Fiber concrete has several advantages compared to conventional cement concrete: a) increased crack resistance, impact toughness, wear, – frost and fire resistance, thermodynamic resistance, etc.; b) the possibility of use without conventional rod or wire steel reinforcement; c) reducing labor costs for reinforcement works, increasing the degree of mechanization and automation of road and airfield pavement construction. In recent years, the use of concrete (cement concrete) foundations and pavements of highways and industrial sites has begun to revive in road construction. The use of various types of cement concrete and fiber concrete (steel fiber concrete, glass fiber concrete, fiber concrete on synthetic fiber) will increase the durability of road and airfield pavements, increasing resistance to shock loads, abrasion and tensile stresses.