Enhancing Properties of Clay Mortars Using Nano-Additives

Abstract

Earthen materials have been used in construction for centuries. Nowadays, a certain appeal towards natural materials rose again due to the various benefits they hold. Besides being inexpensive and approachable, earthen construction offers a clear sustainable method of modern manufacturing. Since earthen materials present high absorption and relatively low compressive strength, the main purpose of this study was to enhance these abilities of clay-based mortars using nanoadditives. To achieve the mechanical and physical invigoration of the clay matrix two different compositions were fabricated by the use of nanoclay, nanosilica and nanoalumina. The addition of nanoclay (NC) at 5%w/w of binder, indicated a lower water absorption and an increase in mechanical properties, while the use of nanosilica and nanoalumina combined at 1.5% and 1% w/w of binder respectively, outline a less stable and compact structure.

Comparative Overview of the Performance of Cementitious and Non-Cementitious Nanomaterials in Mortar at Normal and Elevated Temperatures

“…Similarly, as demonstrated in Figure 5 and the key observations compiled in Table 2 , the addition of other nanomaterials such as nano-alumina, nano-MgO, nano-ZnO, nano-TiO 2 , nano-clay, and carbon nanotubes (CNT) up to the optimum dosage improves the compressive strength [ 52 , 54 , 56 , 61 , 91 , 99 , 129 , 130 , 131 ]. Clearly from the XRD images ( Figure 6 ), the compressive strength increase is due to the flaw-bridging effect and filler effect at the nano level [ 45 , 132 , 133 , 134 , 135 , 136 ], while agglomeration prevents the hydration process due to the formation of weak bonds within the mortar matrix [ 44 , 137 , 138 , 139 , 140 , 141 ].…”

“…The reasons for this is that nano-clay (Nano-CaCO 3 ) makes the diffused Ca 2+ accumulate on its particle surfaces, decreasing the nearby Ca 2+ concentration, and thus accelerating the chemical reaction of C 3 S [ 90 ]. Depending on the chemical morphology and composition of the crystalline, it can be of montmorillonite, kaolinite, halloysite, illite, or vermiculite type [ 91 ].…”

“…In other studies, an increase in compressive strength was observed against the incorporation of nano-silica and nano-metakaolin in high strength mortar at 400 and 250 • C, respectively [75,143]; this may be due to the higher rate of hydration due to the higher availability of SiO 2 . In [103], it was also observed that for nano-silica mortar, the compressive strength increased up to 450 • C and then decreased at higher temperatures up to 1000 • C. TiO2, nano-clay, and carbon nanotubes (CNT) up to the optimum dosage improves the compressive strength [52,54,56,61,91,99,[129][130][131]. Clearly from the XRD images (Figure 6), the compressive strength increase is due to the flaw-bridging effect and filler effect at the nano level [45,[132][133][134][135][136], while agglomeration prevents the hydration process due to the formation of weak bonds within the mortar matrix [44,[137][138][139][140][141].…”

Recent Advancements in the Nanomaterial Application in Concrete and Its Ecological Impact

“…Increased surface roughness and compressive strength [45] Concrete is one of the prominent materials in building industries. Concrete is a mixture of aggregates and paste [46].…”

“…Different types of manufactured nanomaterials can have advantageous utilization in construction, including high-resolution sensing/actuating devices, superior structural properties, and functional coatings and paints [35][36][37][38]. Some utilizations of nanomaterials in the construction industry are presented in Table 1 [39][40][41][42][43][44][45]. 3 Titania nanoparticles Concrete Self-cleaning, increased degree of hydration [41] 4…”