Development of high performance and high strength heavy concrete for radiation shielding structures

Abstract

Heavy concrete currently used for construction contains special materials that are expensive and difficult to work with. This study replaced natural aggregate (stones) in concrete with round steel balls, which are inexpensive and easily obtainable. The diameters of the steel balls were 0.5 and 1 cm, and their density was 7.8 kg/m 3 . Dense packing mixture methods were used to produce heavy concrete with densities of 3500 and 5000 kg/m 3 . The various properties of this concrete were tested according to the standards of the American Society for Testing and Materials (ASTM). The results indicated that the construction slump of the concrete could reach 260-280 mm and its slump flow could reach 610-710 mm. More important, its compressive strength could reach 8848 MPa. These results will significantly alter traditional construction methods that use heavy concrete and enhance innovative ideas for structural design.

Study of the Course of Cement Hydration in the Presence of Waste Metal Particles and Pozzolanic Additives

“…[4][5][6][7][8][9]. Currently, heavy concretes used for construction works contain special costly fillers, such as barite, ilmenite, and Materials 2022, 15, 2925 2 of 20 magnetite [10][11][12]. Usually heavyweight aggregate contains a high content of metallic phases.…”

“…However, the introduction of waste particles as fillers can reduce the material quality of concretes. Thus, replacing some parts of natural aggregates with steel waste particles caused some reduction in strength [11]. It was shown that as the amount of steel waste increased, the workability of the concrete mixture became an important issue which eventually required larger amounts of water to achieve a minimum slump [6][7][8].…”

“…It was shown that as the amount of steel waste increased, the workability of the concrete mixture became an important issue which eventually required larger amounts of water to achieve a minimum slump [6][7][8]. Research showed that the 30-40% replacement of natural fillers by steel shot (density 7.8 kg/m 3 ) with a diameter of 0.5 and 1 cm provided the density of concrete up to 5000 kg/m 3 ; however, the compressive strength of such density samples is by 20% lower than the compressive strength of samples with density 2200 kg/m 3 [11].…”

“…To increase the strength by improving the contact zone between the filler and cement matrix, special additives and admixtures are often used, including nano-sized ones such as nano-silica [51,52], superplasticizers [53], microsilica [7], and metakaolin [54][55][56]. The above-listed pozzolanic additives should be used in heavy concretes to improve the packing density of concrete structures, improve the physical properties of the contact zone between the filler and cement matrix, and decrease the damage of voids and cracks in the concrete [11].…”

Effect of elevated temperature on the mechanical properties and microstructure of heavy-weight magnetite concrete with steel fibers

“…To achieve high densities, some authors have analyzed nonstructural ferrous additions such as iron punchings [18,19] or electric arc furnace slags [12]. These additions considerably improve concrete attenuation coefficients [20].…”