Modified fiber reinforced concrete for industrial floors

Abstract

The main requirements to gain of strength, impact resistance without increasing brittleness, durability of concrete for industrial floors are increasing. It has been shown that the strength of concrete at the impact loads can be increased by means of regulation of the macro-, micro- and nanostructure parameters of the concrete. The kinetics of hardening, peculiarities of pore structure and impact resistance of concrete reinforced with polypropylene fiber and modified by polycarboxylate ether superplasticizer, micro- and nanofine mineral additives are investigated. Nanomodified concretes are characterized by increased rate of early strength development (fcm2/fcm28=0.55) and strength after 28 days (101.5–104.9 MPa), which meets the requirements for rapid hardening high strength concrete. Impact resistance of modified fiber reinforced concrete is determined according to special procedure, which estimate parameter of maximum weight after which the residual impression depth on the surface from impact does not exceed the permissible value (2 mm). The impact resistance of concrete modified with polycarboxylate superplasticizer is 100 and 150 N after 28 and 360 days respectively. Nanomodified fiber reinforced concrete is characterized impact resistance 200 N after 28 and 360 days.

Badania nad odpornością powłok ochronnych dla betonu na działanie wilgoci atmosferycznej

“…However, surveys of structural elements in industrial buildings [1] and bridges [2] demonstrate that several factors affect the durability of concrete or cause structural damage. One of these factors is a change in the internal humidity or temperature of the pores (carbonation, freeze-thaw cycles, wetdry cycles, the influence of chloride salts, and sulphates), as well as the influence of various forms of loading [3][4][5][6].…”

“…By altering the mineralogical composition of the binding material and the hardening conditions, it is possible to obtain different types of cement stone microstructure. The interfacial surface and the inner surface of neoplasms are collectively considered to be the surface that affects the processes of synthesis of properties and corrosion of the stone [6]. The use of engineering cementitious composites (ECC)a developed class of dispersion-reinforced materials based on Portland cementmakes it possible to increase the load-bearing capacity, stability under various static and dynamic influences, and the durability of building structures due to the controlled cracking process.…”

“…Units of measurement must be introduced to assess durability, defining it as a "measure" of a material's resistance to wear and physical and chemical changes under specific conditions of use. Such an interpretation makes it possible to substantiate methods of durability testing, using resistance to influences characteristic of the operating conditions of a given material or structure as a criterion [6,11].…”