Study of the effect of additives of cationic latex butonal ns 198 and basalt fiber on the frost resistance of crushed stone and sand mixtures of iron tailings reinforced with cement

Abstract

One of the directions that contributes to increasing the durability of road construction materials in road surface layers of highways is to increase their frost resistance. During freezing of a material made of crushed stone-sand-cement mixtures, saturated with water, its destruction occurs due to the anomaly of water known from physics. Research has established that in order to obtain a cement-containing material with high frost resistance, it must be prepared with the minimum necessary amount of water, compacted to the maximum density, harden under favorable conditions and contain the optimal volume of pores. Today, the influence of various factors on the frost resistance of materials made of gravel-sand mixtures reinforced with cement remains insufficiently studied, compared to such road construction materials as cement and asphalt concrete. In addition, the impact of the genesis of stone material in crushed stone-sand mixtures reinforced with cement on the resistance of the material in the road wear layer to cyclic freezing and thawing remains insufficiently studied. The purpose of this work is to study the effect of Butonal NS 198 cationic latex additives and basalt fiber on the strength and frost resistance indicators of crushed stone-sand mixtures made of ferruginous quartzite reinforced with cement.

According to the results of the research, it was established that the material made of crushed stone-sand mixtures of SSh 40 made of ferruginous quartzite with 4% cement shows a tendency towards a moderate increase in the values of the compressive strength limit and the ultimate splitting strength along the original in case of adding 0.5% basalt fiber to its composition , as an individual modifying additive. In the case of simultaneous addition of 0.5% basalt fiber and different amounts of cationic latex, a similar pattern is observed. This indicates that the compressive strength and splitting strength indicators are not sufficiently sensitive as criteria for evaluating the effectiveness of the investigated fiber and latex additives at the concentrations adopted in the work. The results of the study of the frost resistance of the material made of crushed stone-sand mixtures reinforced with cement without fiber and latex additives show that the value of its compressive strength limit is 3.2 MPa, and after 10 freeze-thaw cycles it decreased to 1.9 MPa, which is 41% and is essential. This indicates insufficient frost resistance of the material from the crushed stone-sand mixture reinforced with 4% cement. In the case of adding basalt fiber and cationic latex to the composition of the material from crushed stone-sand mixtures reinforced with cement, the values of the residual strength coefficients after 10 freeze-thaw cycles increase significantly. This testifies to the positive effect of fiber and latex additives on increasing the resistance of the material structure to cyclic freezing and thawing, that is, on increasing the frost resistance of the complexly modified material.