Research of Tiredness of Concrete on Limestone Sand

Abstract

Results of experimental researches of durability and deformability of concrete are brought on granite macadam and limestone sand in the conditions of action of the repeatedly repetitive loading. Most building constructions, including crane beams, panels of coverage and overlapping of buildings, coverage of commuter and travelling flags, on that set different oscillation machines, are under the action of the repeatedly repetitive loading. The dynamic loading arises up at landing of airplane and his motion on the uneven surface of coverage. On commuter coverage, except the wheeled loading, powerful gas streams operate during work of aviation ramjets. Destruction of concrete flags can arise up and under the action of the repeatedly repetitive loading, the single action of that creates tension not exceeding possible. For those districts of countries that do not keep reserves of durable lithoidal materials, the use of local tenuous materials and by-products of industry is one of important measures of decline of cost of building of coverages. The use of local materials gives an opportunity of exception of expensive transportations of durable lithoidal materials. To tenuous lithoidal materials it is possible to take: soft limestones and sandstones, brick fight, products of weathering of mountain breeds.

 In connection with lack of quartz sand of southern regions of Ukraine the especial urgency gets use of limestone. Reinforce-concrete constructions made from local materials, in the process of exploitation to the action repeatedly of the repeated loading that requires the estimation of their tireless durability and deformability of such concrete. Works in which influence of cyclic loads on ferro-concrete designs and made on calcareous sand - a little was investigated. The basic normative document which defines the general requirements to concrete and ferro-concrete designs does not contain recommendations on calculation of fatigue strength of the designs made of concrete on calcareous sand.

Research of fatigue strength and deformability of concrete on calcareous sand provides the way to apply ferro-concrete designs which are made of local materials and influenced in service cyclic loads.