Microstructural investigation and strength properties of structural lightweight concrete produced with Zeolitic tuff aggregate

Pekgöz, Mahfuz; Tekin, İlker

doi:10.1016/j.jobe.2021.102863

Cited by 12 publications

(7 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An increase in the cement dose and a drop in the water-to-cement ratio generated C-S-H production. ITZ thicknesses decreased as the lightweight concrete compressive strength increased [ 100 ]. In addition, the geopolymer aggregate concrete generated a fracture network due to the presence of a greater number of microcracks in the cement-geopolymer aggregate transition zone than at the cement-natural aggregate interface at an early age.…”

Section: Interfacial Transition Zone (Itz)mentioning

confidence: 99%

“…Most artificial aggregates are porous and contain air voids, which lead to their classification as lightweight aggregates [ 102 ]. Due to their internal porous structure, artificial aggregates have a higher water absorption rate than natural aggregates [ 91 , 100 , 103 ]. Furthermore, artificial lightweight aggregates are highly porous and spherical, with densities less than 1200 kg/m 3 .…”

Section: Improvement Techniques For Artificial Aggregate-based Geopol...mentioning

confidence: 99%

See 1 more Smart Citation

Geopolymer-Based Artificial Aggregates: A Review on Methods of Producing, Properties, and Improving Techniques

et al. 2022

View full text Add to dashboard Cite

The depletion of aggregate-related natural resources is the primary concern of all researchers globally. Recent studies emphasize the significance of recycling and reusing various types of natural or by-product material waste from industry as a result of the building industry’s rising demand for aggregate as the primary component in concrete production. It has been demonstrated that the geopolymer system has exceptional features, such as high strength, superior durability, and greater resistance to fire exposure, making it a viable alternative to ordinary Portland Cement (OPC) concrete. This study will examine the present method utilized to generate artificial aggregate-based geopolymers, including their physical and mechanical properties, as well as their characterization. The production process of geopolymer derived from synthetic aggregates will be highlighted. In conjunction with the bonding of aggregates and the cement matrix, the interfacial transition zone (ITZ) is highlighted in this work as an additional important property to be researched in the future. It will be discussed how to improve the properties of geopolymers based on artificial aggregates. It has been demonstrated that cold bonding provides superior qualities for artificial aggregate while conserving energy during production. The creation of ITZ has a significant impact on the bonding strength between artificial aggregates and the cement matrix. Additionally, improvement strategies demonstrate viable methods for enhancing the quality of manufactured aggregates. In addition, other recommendations are discussed in this study for future work.

show abstract

Section: Interfacial Transition Zone (Itz)mentioning

confidence: 99%

Section: Improvement Techniques For Artificial Aggregate-based Geopol...mentioning

confidence: 99%

Geopolymer-Based Artificial Aggregates: A Review on Methods of Producing, Properties, and Improving Techniques

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Two key aspects were highlighted in this research: specimens with added mordenite are lighter and more resistant. Many researchers, including Karakurt et al [62], Barnat-Hunek et al [63], Pekgöz and Tekin [64], Sai Teja et al [65] and Vijayan et al [66], among others, consider zeolites to be high-performance light aggregates capable of decreasing the excessive density of concretes and mortars.…”

Section: Effects Of Mordenite On the Density Of Fresh Mortar And Specimensmentioning

confidence: 99%

Effects of a Natural Mordenite as Pozzolan Material in the Evolution of Mortar Settings

et al. 2021

View full text Add to dashboard Cite

This paper shows the results of a study focused on the evolution and properties of mortars made with a mixture of portland cement (PC) and natural mordenite (Mor). To begin, samples of mordenite, cement and sand were studied with X-ray diffraction (XRD), X-ray fluorescence (XRF) and granulometric analysis (GA). Next, mortars with a ratio of 75% PC and 25% mordenite were prepared to determine their initial and final setting times, consistency and density. Continuing, the density, weight and compressive strength of the specimens were determined at 2, 7, 28, 90 and 365 days. Finally, the specimens were studied using SEM, XRD and XRF. The results of the study of the mordenite sample showed a complex constitution where the major mineral component is mordenite, and to a lesser degree smectite (montmorillonite), halloysite, illite, mica, quartz, plagioclase and feldspar, in addition to altered volcanic glass. Tests with fresh cement/mordenite mortar (CMM) showed an initial setting time of 320 min and a final setting time of 420 min, much longer than the 212–310 min of portland cement mortar (PCM). It was established that the consistency of the cement/mordenite mortar (CMM) was greater than that of the PCM. The results of the density study showed that the CMM has a lower density than the PCM. On the other hand, the density of cement/mordenite specimens (CMS) was lower than that of portland cement specimens (PCS). The CMS compressive strength studies showed a significant increase from 18.2 MPa, at 2 days, to 72 MPa, at 365 days, with better strength than PCS at 28 and 365 days, respectively. XRD, XRF and SEM studies conducted on CMS showed a good development of primary and secondary tobermorite, the latter formed at the expense of portlandite; also, ettringite developed normally. This work proves that the partial replacement of PC by mordenite does not have a negative effect on the increase in the mechanical strength of CMS. It indicates that the presence of mordenite inhibits the spontaneous hydration of C3A and controls the anomalous formation of ettringite (Ett). All this, together with the mechanical strength reported, indicates that mordenite has a deep and positive influence on the evolution of the mortar setting and is an efficient pozzolan, meaning it can be used in the manufacture of mortars and highly resistant pozzolanic cement, with low hydration heat, low density, stability in extremely aggressive places and a low impact on the environment.

show abstract

“…The interest in lightweight characteristics for structures is growing of late in the concrete and construction industries. A representative method for reducing the weight of structures is to utilize lightweight aggregates, and many studies on lightweight aggregate concrete have been conducted [15][16][17][18][19][20][21]. However, lightweight aggregates are not only vulnerable to external forces because of the numerous pores distributed inside them but they also absorb mixing water from concrete, reducing the concrete's fluidity [16,[22][23][24][25][26].…”

Section: Introductionmentioning

confidence: 99%

Mechanical and Electrical Characteristics of Lightweight Aggregate Concrete Reinforced with Steel Fibers

et al. 2021

View full text Add to dashboard Cite

There is increased interest in applying electromagnetic (EM) shielding to prevent EM interference, which destroys electronic circuits. The EM shielding’s performance is closely related to the electrical conductivity and can be improved by incorporating conductive materials. The weight of a structure can be reduced by incorporating lightweight aggregates and replacing the steel rebars with CFRP rebars. In this study, the effects of lightweight coarse aggregate and CFRP rebars on the mechanical and electrical characteristics of concrete were investigated, considering the steel fibers’ incorporation. The lightweight coarse aggregates decreased the density and strength of concrete and increased the electrical conductivity of the concrete, owing to its metallic contents. The steel fibers further increased the electrical conductivity of the lightweight aggregate concrete. These components improved the EM shielding performance, and the steel fibers showed the best performance by increasing shielding effectiveness by at least 23 dB. The CFRP rebars behaved similarly to steel rebars because of their carbon fiber content. When no steel fiber was mixed, the shielding effectiveness increased by approximately 2.8 times with reduced spacing of CFRP rebars. This study demonstrates that lightweight aggregate concrete reinforced with steel fibers exhibits superior mechanical and electrical characteristics for concrete and construction industries.

show abstract

Microstructural investigation and strength properties of structural lightweight concrete produced with Zeolitic tuff aggregate

Cited by 12 publications

References 49 publications

Geopolymer-Based Artificial Aggregates: A Review on Methods of Producing, Properties, and Improving Techniques

Geopolymer-Based Artificial Aggregates: A Review on Methods of Producing, Properties, and Improving Techniques

Effects of a Natural Mordenite as Pozzolan Material in the Evolution of Mortar Settings

Mechanical and Electrical Characteristics of Lightweight Aggregate Concrete Reinforced with Steel Fibers

Contact Info

Product

Resources

About