The Impact of Long-Term Physical Salt Attack and Multicycle Temperature Gradient on the Mechanical Properties of Spun Concrete

Abstract

The article is focused on spun concrete made with different chemical admixtures under long-term exposure to aggressive salt-saturated ground water and a cyclic temperature gradient. Over a long-term experimental investigation, 64 prismatic spun concrete specimens were subjected to multicycle (75–120) processing under combined aggressive ambient conditions. Prismatic specimens were soaked in water or saline and dried at a temperature of 45–50 °C. The long-term multi-cycle effect of the temperature gradient and physical salt attack on the compressive strength, Young’s modulus and durability of concrete was found to be negative. Chemical admixtures, though, improved the structure of spun concrete, thus having a significant positive effect on its physical-mechanical properties and durability.

Nano-Modified Vibrocentrifuged Concrete with Granulated Blast Slag: The Relationship between Mechanical Properties and Micro-Structural Analysis

“…From the point of view of methodology, we have developed previously obtained theoretical concepts and applied dependencies arising from the influence of various prescription, technological, and other factors on the structure and properties of variotropic concretes. Earlier in this study, we established the fundamental possibilities and substantiated the recipe-technological feasibility of obtaining an improved variotropic structure due to the additional technological impact of adding a vibration component to centrifugal forces [44][45][46][47][48].…”

“…For further analysis and comparison of the results obtained with the data obtained earlier in [44][45][46][47][48], three blocks can be conditionally distinguished: methodology, a structural component, and a resulting component. From the point of view of methodology, we have developed previously obtained theoretical concepts and applied dependencies arising from the influence of various prescription, technological, and other factors on the structure and properties of variotropic concretes.…”

“…One of the most effective types of building structure is the hollow structures with an annular section, primarily obtained via centrifugal compaction methods [43]. This method, in turn, as is known from our previous works and the works of other authors, can be improved by transforming it using the vibrocentrifugation method [43][44][45][46][47][48]. This aims to achieve the so-called variotropic structure in such concrete and in such structures.…”

Influence of Concrete Strength Class on the Long-Term Static and Dynamic Elastic Moduli of Concrete

“…The conversion equations from compressive strength to static modulus of elasticity were checked for their accuracy and suitability for being applied to rubberized concrete, although they were not specifically developed and proposed for this purpose. Hence, the equation given by Eurocode 2 [11], Equation (9), and the equation given in ACI 318-14 [28], Equation (10), were investigated. The obtained results are summarized in Table 6.…”

“…They are subjected to repeated freeze-thaw cycles during their lifetime in conjunction with various other environmental factors and chemical attacks. The influence of different admixtures on the long-term durability and strength characteristics were investigated and reported in a previous study [9].…”