Study of using micro‐nano bubble to improve workability and durability of self‐compact concrete

Abstract

Developing self‐compacting concrete (SCC) with higher workability and durability properties by replacing mixing water with nano‐bubble without a decrease in mechanical strength is the purpose of this study. For this aim, different SCC mixtures were designed by using tap water and micro‐nano bubble and replacing silica fume, fly ash, slag, zeolite, and the mixture of fly ash and silica fume with cement. The workability, mechanical, and durability properties of the SCC mixture were tested according to ASTM and BS standards. In addition to air content test, for evaluation of the workability of SCCs, Slump flow in 10 and 60 min (for filling ability), V‐funnel, L Box, and J‐ring (for passing ability) were tested. For mechanical properties (compressive and tensile strength) and for durability of concretes (water penetration test and electrical resistivity) were tested. The workability test results indicate that using a micro‐nano bubble instead of tap water in different SCC mixture designs did not make a significant difference. But in hardened concretes, using the micro‐nano bubble increase the compressive and tensile strength of different concrete mixture designs except for SCC including fly ash and silica fume. Depth of water penetration and 30 min water adsorption for different concrete mix designs decreased compared to using tap water except for the sample contain zeolite, which increased slightly. Also, the permeability of concrete was tested by electrical resistivity. The results indicate that using the micro‐nano bubble decrease electrical resistivity and they were in the very low range (37–254 Ω‐m). The scanning electron microscope image confirmed in increasing mechanical and durability properties for a sample where used the micro‐nano bubble without pozzolans.

Study of shear‐thickening and shear‐thinning behavior in rheology of self‐compacting concrete with micro‐nano bubble

“…Arefi et al, 2 Khoshroo et al, 34 Asadollahfardi et al, 3 Mohsenzadeh et al, 56 Sheikh Hassani et al 51 used micronano bubbles to produce concrete, and Yahyaei et al 55 used micro-nano bubbles to produce SCC.…”

“…The authors also studied the workability, mechanical, and durability properties of selfcompacting concrete (SCC) using a micro-nano bubble instead of tap water previously. 55 None of these studies perused the rheology of SCC, that's made with micronano bubbles.…”

“…A few numbers of research have been carried out using nanobubbles in normal concrete in which the workability, mechanical properties, and durability have been investigated ( 2,3,27,34,36,42,44 ; Sheikh Hassani et al, 58 ). The authors also studied the workability, mechanical, and durability properties of self‐compacting concrete (SCC) using a micro‐nano bubble instead of tap water previously 55 . None of these studies perused the rheology of SCC, that's made with micro‐nano bubbles.…”

Properties and durability of self‐compacting concrete incorporated with nanosilica, fly ash, and limestone powder

“…36 Accordingly, the inclusion of binary and ternary mixtures of NS and microsilica has a positive effect on the durability and performance of SCC because of the role played by nanomaterials to thicken the cement paste and fill the nano-sized pores. 37,38 Using NS or combining NS and microsilica in the mixtures studied produces concretes with high compactness, consequently improving durability properties. These features lead to less susceptibility to carbonation and freeze-thaw cycles, as well as lower capillary absorption that may prevent the penetration of aggressive agents, leading to increased life span of concrete.…”

“…Therefore, the chemical effect of acids and salts (sulfates and alkalis) on concrete varies based on the microstructure of the concrete matrix 36 . Accordingly, the inclusion of binary and ternary mixtures of NS and microsilica has a positive effect on the durability and performance of SCC because of the role played by nanomaterials to thicken the cement paste and fill the nano‐sized pores 37,38 . Using NS or combining NS and microsilica in the mixtures studied produces concretes with high compactness, consequently improving durability properties.…”