Effect of nano silica on cement mortars containing micro silica

Abstract

The use of cement and concrete is becoming increasingly widespread all over the world. However, the high energy consumption required for the production of clinker and the greenhouse gas emissions generated during production negatively affect both the economy and the environment. In the studies conducted for many years, researchers have found that the substitution of various pozzolans with cement provides both technical advantages and environmental benefits. The use of pozzolans in cementitious composites provides advantages such as the improvement of the physical and mechanical properties of the material, the conservation of the environment and the economy in terms of the evaluation of industrial wastes. In recent years, studies on the use of nanoparticles in cementitious composites are positively. In this study, it was aimed to investigate the properties of fresh and hardened cement mortars using micro silica as pozzolan and nano silica as nanoparticle. For this purpose, four different cement pastes and mortars mixtures were prepared by substituting 0%, 1%, 2%, 3% nano SiO2 (silica) cement in mortar mixtures containing 5% micro silica. The effects of the nano silica on the micro silica-containing cement paste on the consistency and setting time were investigated. The mortar mixtures produced were subjected to flexural and compressive strength tests on days 7, 28 and 90th. SEM images of mortar mixtures were taken. As a result, it was found that 2% nano silica admixture of 5% micro silica containing cement admixture affects the flexural and compressive strength positively, whereas 2% nano silica admixture increased the flexural strength by 13% and compressive strength by 7%.

Systematic Multiscale Models to Predict the Compressive Strength of Cement Paste as a Function of Microsilica and Nanosilica Contents, Water/Cement Ratio, and Curing Ages

“…In total, 205 experimental data from previous publications [33][34][35][36][37] were gathered. The mortar cubes in those publications were determined according to IS 2250-1981, and their size in four papers [33,34,36,37] was 50 × 50 × 50 mm 3 , and in just one of them [35], the model size of (40 × 40 × 40) mm 3 was used.…”

“…In total, 205 experimental data from previous publications [33][34][35][36][37] were gathered. The mortar cubes in those publications were determined according to IS 2250-1981, and their size in four papers [33,34,36,37] was 50 × 50 × 50 mm 3 , and in just one of them [35], the model size of (40 × 40 × 40) mm 3 was used. The criteria for collecting the data was based on compressive strength test, experimental data, and updated credible journals from 2017 to 2020, with studies including cement mortar adjusted by MS and NS without other admixtures and subjected to the same curing conditions.…”

Öğütülmüş Kolemanit Minerali İkameli Beton Yollardaki Aşınma Kaybının Araştırılması

“…Çalışmada aşınma kaybı ve yaklaşık basınç dayanımı ile kolemanit minerali ikame oranı arasında doğrusal olmayan bir ilişkinin olduğu söylenebilir. Dayanım ve ikame oranı arasında literatürde benzer ilişkinin olduğu görülmektedir (Kutuk-Sert 2016, Bekem Kara 2019. Schmidt çekici yöntemi ile elde edilen yaklaşık basınç dayanımı değerleri Şekil 4'de verilmiştir.…”

Retrofitting and waterproofing of Aged Concrete Using Electromigration of Nanosilica

“…For example, 100 billion euros are spent in new buildings annually in Germany with a similar cost for maintenance of the existing buildings. Nano Silica as a retro tting material has a great advantage, especially when used with active silica (Kara and Durmus 2019). It is a great alternative to develop high strength concrete, or mortar, reducing consumption of cement and increasing lifetime of constructions.…”