Macro/micro-pore structure characteristics and the chloride penetration of self-compacting concrete incorporating different types of filler and mineral admixture

Abstract

The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.uk 1 Macro/Micro-pore structure characteristics and the chloride penetration of self- might be, primarily, responsible in determining the chloride ions' migration velocity especially when coarse and unreactive filler is used. At nano scale, it is also suggested that the critical pore diameter in the cement matrix is more significant than is the average pore diameter in controlling the chloride resistance in SCC.

RETRACTED: Comparative study on effects of Class F fly ash, nano silica and silica fume on properties of high performance self compacting concrete

“…As observed in water absorption results, this performance may be attributed to the more packed microstructure and pore structure of the concrete by addition of fly ash. At the nano scale, the results demonstrated that the chloride penetration velocities were more closely related to the change in the CPDs in the cement matrix than to the APDs, including the capillary pores, in both the ITZ and the cement matrix as detected by the MIP [41].…”

“…Furthermore, the charges passed of FA concrete were higher than that of SF concrete [44]. Another study demonstrates that the use of lime stone (LP) at relatively high replacement of cement increased the chloride penetration velocity of LP-SCC as compared with both the use of cement only (without any replacement) and the incorporating of mineral admixture such as FA and FA + SF at the same replacement percentage [41]. Results of water absorption and catalyzed chloride ion penetration tests show that nanosilica has a great influence on the reduction of water absorption and chloride ion penetration into fiber-reinforced concrete [49].…”

“…Addition of fly ash up to 15% reduced the T v-f values from 9 s to 6 s, and 4 s to 2.5 s for cement content of 400 and 500 kg/m 3 respectively. Findings by other authors show that addition of lime stone and fly ash increase the slump flow of SCC and their combination lead to optimized consistency in terms of slump flow time and diameter [41]. Diamantonis et al found that limestone is the best fine material that can be used as a fine additive, among fly ash, silica fume, and nano silica in their study.…”

“…Some researchers explain that nano-SiO 2 can absorb the Ca(OH) 2 crystals, and reduce the size and amount of the Ca(OH) 2 crystals, thus making the interfacial transition zone (ITZ) of aggregates and binding paste matrix denser [56]. Others found that the modification in the chemistry of the ITZ due to the use of different fillers and mineral admixture as a high partial replacement leads to different ITZ porosities which was more noticeable in the case of using the FA + SF replacement [41]. Yu et al concluded that the simultaneous addition of nanosilica and hybrid fibers into UHPFRC can effectively restrict and minimize the cracks leading to significant enhancement of mechanical properties of the designed UHPFRC with waste bottom ash (WBA) [48].…”

“…It was also maintained that the chloride migration coefficient is proportional to both the thickness and the porosity of the ITZ. High ITZ thickness can increased the capillary pore's percolation in the ITZ and thus ITZ thickness was more responsible than ITZ porosity alone in determining the chloride ingress [41].…”